Health and Safety
Executive

Asbestos: The licensed
contractors’ guide
Health and Safety
Executive

Asbestos: The licensed
contractors’ guideThis is a free-to-download, web-friendly version of HSG247(First edition, published 2006). This version has been adapted for online usefrom HSE’s current printed version.
You can buy the book at www.hsebooks.co.uk and most good bookshops.
ISBN 978 0 7176 2874 2
Price £14.50
This book replaces most earlier HSE guidance on licensed asbestos removal
work. It is aimed at businesses holding a licence to work with asbestos, either
repairing or removing asbestos-containing materials (ACMs), supervising such
work, holding an ancillary licence or providing training on asbestos. Employers
who carry out work with asbestos insulation, asbestos coating, and asbestos
insulating board using their own employees on their own premises, who are
exempted from the requirement to hold a licence, also need this guidance. It will
also be useful to people awarding contracts for such work or who have otherasbestos management duties.
The guidance is split into eight chapters, covering different aspects of licensed
work with ACMs. It provides an overview of asbestos and its health effects, thelaw and how to work safely with asbestos.

HSE Books

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Health and Safety
Executive© Crown copyright 2006
First published 2006
Reprinted 2012
ISBN 978 0 7176 2874 2
You may reuse this information (excluding logos) free of charge in any format or
medium, under the terms of the Open Government Licence. To view the licence
visit www.nationalarchives.gov.uk/doc/open-government-licence/, write to the
Information Policy Team, The National Archives, Kew, London TW9 4DU, or email
psi@nationalarchives.gsi.gov.uk.
Some images and illustrations may not be owned by the Crown so cannot be
reproduced without permission of the copyright owner. Enquiries should be sent tocopyright@hse.gsi.gov.uk.
This guidance is issued by the Health and Safety Executive. Following the guidanceis not compulsory and you are free to take other action. But if you do follow theguidance you will normally be doing enough to comply with the law. Health andsafety inspectors seek to secure compliance with the law and may refer to thisguidance as illustrating good practice.

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Contents
List of abbreviations 4
Working with ACMS: Guidance map 5

Chapter 1

An introduction to working with asbestos-containing materials(ACMs) 7

Chapter 2

Licences for work with ACMs

28

Chapter 3		Risk assessments, plans of work and notifications for workwith ACMs 38
Chapter 4		Training for employees, supervisors and others working
with ACMs 54
Chapter 5

PPE for work with ACMs

75

Chapter 6

Enclosures for work with ACMs

87

Chapter 7		Controlled techniques for the removal and repair of ACMs, including 		
waste disposal 111
Chapter 8

Decontamination

156

References and further information 178

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List of abbreviations
ACAD			Asbestos Control and Abatement Division (see Appendix 1.1)
ACOP			Approved Code of Practice
ACM			
Asbestos-containing material
AIB 		
Asbestos insulating board
ALG			
Asbestos liaison group
ALH			
Ancillary license holder
ALPI			Asbestos Licensing Principal Inspector
ALU			
Asbestos Licensing Unit
ARCA			Asbestos Removal Contractors Association (see Appendix 1.1)
ATAC			Asbestos Testing and Consulting (see Appendix 1.1)
ASLIC			Asbestos Licensing Regulations 1983
BA			Breathing apparatus
BOHS			British Occupational Hygiene Society (see Appendix 1.1)
CABA			Compressed airline breathing apparatus
CAWR		 Control of Asbestos at Work Regulations 2002
CDG			
Carriage of Dangerous Goods and Use of Transportable Pressure 					
Receptacles Regulations 2004
CDM 			Construction (Design and Management) Regulations 1994
COSHH
Control of Substances Hazardous to Health Regulations 2002 (as 					amended)CSCS			Construction Skills Certification scheme
DCU			
Decontamination unit (also called ‘Hygiene facilities’ and ‘Hygiene 					unit’)
DOP			
Dioctyl phthalate (test)
EA			Environment Agency
EMAS			Employment Medical Advisory Service
HSE			
Health and Safety Executive
HSWA		 The Health and Safety at Work etc Act 1974
IEE			
Institution of Electrical Engineers
LARC			Licensed asbestos removal contractor
LEV			
Local exhaust ventilation
LPG			
Liquid petroleum gas
MCG			
Main Contractors GroupNPU			
Negative pressure unit
NVQ			
National Vocational Qualification
PAS			
Publicly Available SpecificationPF			
Protection factor
POW			
Plan of work
PPE			
Personal protective equipment
PVA			
Polyvinyl acetate
PVC			
Polyvinyl chlorideRA			
Risk assessment
RCD			
Residual current device
RPE			
Respiratory protective equipment
SCBA			Self-contained breathing apparatus
SEPA			Scottish Environment Protection Agency
SLH			
Supervisory license holder
TNA			
Training needs analysis
TWA			
Time weighted average
UKAS			United Kingdom Accreditation Service

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Working with ACMS: Guidance map
This ‘Guidance map’ provides a quick reference guide to specific topics and key issues in this guide. The items
are identified by paragraph numbers.

Planning for asbestos removal work
Topic

Key issues

Reference

Licence to workwith asbestos

When is a licence required?

Paras 2.2-2.4

Types of licences

Paras 2.7-2.10

How to obtain a licence

Paras 2.11-2.19

Enforcement

Paras 2.20-2.23

Hiring of employees

Paras 2.25-2.34

Consultation with employees

Paras 1.8-1.11

Training

Paras 4.1-4.41 andAppendices 4.1-4.4

Medical surveillanceParas 1.47-1.57

Personal exposure monitoring

Paras 1.24-1.31

Respiratory protective
equipment

Selection

Paras 5.7-5.13

Fit testing

Paras 5.14-5.20

Care and maintenanceParas 5.21-5.24

Selection and use

Paras 5.30-5.36

Laundering

Paras 8.43-8.46

Asbestos
removal workers

Coveralls
Planning forasbestos work

Enclosures

Asbestos
removal/repair

Risk assessments

Paras 3.4-3.15

Plan of work

Paras 3.16-3.31

Notifications/waivers

Paras 3.32-3.44

Site preparation

Paras 6.27-6.29

Paperwork required on site

Para 3.45

Standard of equipment

Box 7.1

Enclosures: When required

Paras 6.5-6.10

Construction

Paras 6.30-6.40

DesignParas 6.13-6.26

Site preparation and pre-clean

Paras 6.27-6.29

Negative pressure units

Paras 6.41-6.47

Testing and monitoring

Paras 6.48-6.59

Smoke tests

Paras 6.50-6.52

Viewing panels

Para 6.23

Air monitoring

Para 6.56

Dismantling and disposal

Paras 6.60-6.67

Emergency procedures

Paras 6.68-6.70

Pre-cleaning

Paras 6.27-6.28

Stripping techniques

Paras 7.6-7.67

Cleaning and waste disposal

Paras 7.87-7.101

Four-stage clearance

Paras 7.102-7.146

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Decontamination Types of decontamination unit

Paras 8.22-8.27

Design criteria for decontamination units

Appendix 8.1

Procedures

Paras 8.4-8.21 andFigures 8.8-8.12

Decontamination unit services

Para 8.28-8.36

Maintenance and cleaning

Paras 8.37-8.42

Showering and laundering

Paras 8.43-8.47

Clearance of decontamination unit

Paras 7.146-7.148

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Chapter 1: An introduction
to working with asbestoscontaining materials (ACMs)

SummarynnnnnAsbestos exposure causes severe and fatal diseases.
Only work on asbestos if absolutely necessary.
Asbestos work should be strictly controlled and comply with the legislation.
Poorly controlled work will produce very high fibre levels.
Asbestos medical examinations are required when exposure exceeds the actionlevel for asbestos fibres.

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Contents
Introduction

9

About this guidance 9
Who is the guidance for? 10
How to use this guidance 10
Consulting employees 10

Health effects and exposure

11

What are asbestos diseases? 11
Working practices and exposure 13
Air monitoring 14

Legal requirements

16

The Control of Asbestos at Work Regulations 2002 16
The Asbestos (Licensing) Regulations 1983 (as amended) 18

Management of asbestos

18

Is asbestos removal necessary? 18

Medical examination of asbestos removal workers under CAWR 2002
Status of the medical examination and certificate of examination 19
Risk assessment of the work conditions 19
When is a medical required? 20
How often is the medical examination carried out? 20
The purpose of the examination
20
Who carries out the medical examination? 20
The content of the medical examination 21
Certificate of examination 21

Appendix 1.1 Materials identified as containing asbestos

19

22

Appendix 1.2 Sprayed asbestos coatings and pipe and vessel insulation in poor
condition 23
Appendix 1.3 AIB and insulating blocks in poor condition

24

Appendix 1.4 Other asbestos materials in poor condition

25

Appendix 1.5 Further information

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Introduction
About this guidance
1.1This guidance publication covers work with asbestos, which requires alicence under the Asbestos (Licensing) Regulations 1983 (as amended).1 HSE
guidance on non-licensed asbestos work is contained in other publications,Asbestos essentials task manual: Task guidance sheets for the building
maintenance and allied trades2 and Working with asbestos cement.3 This licensed
contractors’ guidance is split into eight chapters, covering in detail, different aspectsof licensed work with asbestos-containing materials (ACMs). These chapters are:
Chapter 1: An introduction to working with ACMs (this chapter)
Chapter 2: Licences for work with ACMs
Chapter 3: Risk assessments, plans of work and notifications for work with ACMs
Chapter 4: Training for employees, supervisors and others working with ACMs
Chapter 5: PPE for work with ACMs
Chapter 6: Enclosures for work with ACMs
Chapter 7: Controlled techniques for the removal and repair of ACMs, including
waste disposal
Chapter 8: Decontamination

Box 1.1 Key facts about asbestos■■ Asbestos-related diseases kill more people than any other single work-related

illness.
■■ Asbestos-related diseases can take 15-60 years to develop and there is nocure.
■■ Asbestos-related diseases are currently responsible for more than 4000 deaths

a year in the UK and the number is still increasing.
■■ ACMs in good condition and left undisturbed cannot cause ill health.
■■ The greater the disturbance of ACMs (see Figure 1.1) and the longer theduration, the greater the risk to health.
■■ Effective control of exposure can only be achieved if techniques that minimise

fibre generation have been used, in particular wet stripping.
■■ Power-assisted respirators provide insufficient protection when removal is 		

uncontrolled, eg during dry stripping.
1.2This introduction covers the general principles of asbestos and its licensed
removal. It provides an overview of asbestos and its health effects, the law and how
to work safely with asbestos.
1.3
This guidance replaces and consolidates into one document, most HSE
guidance on licensed asbestos removal work. The publications replaced by thisdocument are:nnControlled asbestos stripping techniques for work requiring a licence(HSG189/1)
Selection of suitable respiratory protective equipment for work with asbestos(INDG288(rev1))

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The provision, use and maintenance of hygiene facilities for work with asbestos
insulation, asbestos coating and asbestos insulating board (EH47 (Third
edition))Training operatives and supervisors for work with asbestos insulation, asbestos
coating and asbestos insulating board (EH50)
Enclosures provided for work with asbestos insulation, coatings and insulatingboard (EH51)

Who is the guidance for?
1.4
Any business holding a licence to work with asbestos, eg either repairing or
removing ACMs, supervising such work, carrying out ancillary activities, supplying
labour or who provide training on asbestos must read this guidance. It is alsoessential for employers carrying out work with asbestos insulation, asbestos
coating, and asbestos insulating board (AIB) using their own employees on theirown premises, who are exempted from the requirement to hold a licence (seeparagraph 2.4). It may also be beneficial to those who award contracts for suchwork or have other asbestos management duties.

Figure 1.1 Asbestos fibres
being released from lagging

How to use this guidance
1.5This guidance should be used as a reference, covering all aspects oflicensed work with ACMs. Each of the chapters covers a broad topic area,eg training, and has its own contents list. You can go direct to the chapter you
need and use the contents list to navigate that chapter. Where appendices areused for a particular topic, these are kept within the relevant chapter.
1.6
This introductory chapter also contains an overview of the complete
process, from licence application through to waste disposal. This overview provides
references for all topics, allowing you to navigate easily to specific topics, eg thefour-stage clearance procedure. This overview also acts as a quick reference,
showing key issues at a glance.
1.7
If you still need help after reading this guidance, Appendix 1.5 contains
details of organisations that may be able to provide further advice andexpertise.
Consulting employees
1.8
Proper consultation with those who do the work is crucial to help raiseawareness of the importance of health and safety. It can make a significant
contribution to creating and maintaining a safe and healthy working environment
and an effective health and safety culture. In turn this can benefit the business bymaking it more efficient by reducing the number of accidents and the incidents ofwork-related ill health.

Involving operatives in decision-making can improve the quality of
the job and reduce exposures
1.9
It is important that employees and employee or safety representatives are
involved in the assessment and planning process. Employees will provide moreaccurate information on the actual work methods used and on the feasibility of new
proposals. For example, if proposed work methods are difficult or cumbersome,
employees may take short cuts that lead to a deterioration in control. Setting
unrealistic timescales for contracts may also result in workers taking less care whenworking with asbestos. Employees generally have greater acceptance of work
methods if they have been part of the decision-making process.
1.10 It is particularly important that the wearers of respiratory protective
equipment (RPE) are involved in the selection process and, where practicable, areAsbestos: The licensed contractor’s guide

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provided with a choice of suitable equipment. This helps to ensure it is suited tothem and increases the chances that they will accept the RPE and wear it correctly.
1.11 Safety representatives, where appointed by recognised trade unions under
the Safety Representatives and Safety Committees Regulations 1977,4 must be
consulted. Safety representatives can play a crucial role in health and safety inthe workplace. They can bring ideas and experiences from outside the employer’sorganisation (eg as a result of trade union training). They also form a link between
the workers and management. The presence of safety representatives in theworkplace has been shown to cut the major accident rate by more than 50%.
Other employees not covered by such representatives must be consulted, either
directly or indirectly via elected representatives of employee safety, according to
the Health and Safety (Consultation with Employees) Regulations 1996.5 This willallow employees or their representatives to help develop suitable and adequate
control measures. More information on employers’ duties under these regulations
is contained in the free HSE leaflet Consulting employees on health and safety: A
guide to the law.6

Health effects and exposure
What are asbestos diseases?		
		
1.12 Breathing in asbestos fibres can lead to asbestos-related diseases, whichkill more people than any other single work-related illness. The diseases can takemany years to develop - so you and your employees will not be immediately awareof a change in someone’s health after breathing in asbestos.
1.13 Asbestos can cause two main types of damage in humans: cancer, eg
mesothelioma or lung cancer; and fibrous thickening of the lung, asbestosis.
Other diseases, such as pleural plaques, are less serious as they are not disabling.
Mesothelioma and lung cancer are severely disabling and most result in death.
Severe asbestosis can contribute to death. Figure 1.2 shows normal healthylung tissues. Figures 1.3, 1.4 and 1.5 show lung tissue from lungs of workers
overexposed to asbestos. These conditions, which are described below, can beprevented by good working practices as outlined in this guidance.

Figure 1.2 Normal lung

Figure 1.3 Heavy exposure
to asbestos

Figure 1.4 Lung cancer

Figure 1.5 Mesothelioma
due to asbestos exposure

Asbestos-related diseases kill more people than any other single
work-related illness
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There is no cure for asbestos-related diseases
What is asbestosis?
1.14 Asbestosis is a scarring of the lung tissue which restricts breathing,leading to decreased lung volume and increased resistance in the airways. It is a
slowly progressive disease with a latency period dependent on the magnitude of
exposure.
What is mesothelioma?
1.15 Mesothelioma is a cancer of the cells that make up the lining aroundthe outside of the lungs and inside of the ribs (pleura), or around the abdominalorgans (peritoneum). By the time it is diagnosed, it is almost always fatal. Similar
to other asbestos-related diseases, mesothelioma usually has a long latency
period averaging 30-40 years. However there are cases where the latency period
has been much shorter (around 15 years). There is no known safe threshold of
exposure, therefore as the frequency, duration and level of exposure increases, sodoes the risk of developing mesothelioma.
What is lung cancer?
1.16 Lung cancer is a malignant tumour of the lungs’ air passages. The tumour
grows through surrounding tissue, invading and often obstructing air passages.
The time between exposure to asbestos and the occurrence of lung cancer is on
average 20-30 years. There is a synergistic effect between smoking and asbestos
exposure. If you smoke and are exposed to asbestos, your risk of developing lungcancer is greatly increased.

Exposure to asbestos and smoking multiplies the risk of developing
lung cancer
What are the symptoms?
1.17 Each of these asbestos-related diseases can only be diagnosed throughmedical examinations and tests. Exposure to asbestos does not mean that these
diseases will develop. However, the greater the exposure, the greater the risk ofcontracting them.
1.18 The symptoms of asbestos-related diseases will usually not become
apparent for several decades after exposure. They may include:
n
n
n
n
n
n
Figure 1.6 Controlled
removal of asbestos

shortness of breath;a cough or a change in cough pattern;blood in the sputum (fluid) coughed up from the lungs;
pain in the chest or abdomen;difficulty in swallowing or prolonged hoarseness; and/or
significant weight loss.

1.19 Once the asbestos-related disease has been diagnosed, the individual isleft with the prospect of a debilitating impact on their health or eventual death.
Therefore exposures should always be prevented or minimised to the lowest levelreasonably practicable to reduce the risk of ill health later in life.

Reduce exposures now to prevent ill health in the future

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Asbestos should only be worked on if absolutely necessary

Figure 1.7 Uncontrolled
removal of asbestos

Uncontrolled removal of asbestos costs lives
Using controlled methods of removal saves lives
Working practices and exposure
1.20 There are three main types of asbestos which have been commonly used:nnncrocidolite (‘blue’);amosite (‘brown’);chrysotile (‘white’).

1.21 All types of asbestos are dangerous but crocidolite and amosite asbestos
are known to be more hazardous than chrysotile. The asbestos types are often
referred to by their colour. But, it is very difficult to identify them by colour. Colour
and appearance can be affected in many ways, including by heat and chemicals,
mixing with other substances and through painting or coating.
1.22 Although asbestos is a hazardous material, it can only pose a risk to health
if the asbestos fibres become airborne and are then inhaled. ACMs only releasefibres into the air when they are disturbed. Also, the greater the disturbance of the
ACM during removal, the greater the risk to health. Controlled stripping techniques
reduce exposure and therefore the risk of ill health and death (see Figures 1.6
and 1.7). Factors affecting exposure are listed in Box 1.2.
1.23 The number of asbestos fibres in air is affected by many factors. An
estimate of the expected concentration of asbestos fibres in air can be made byconsidering:		n the type of asbestos (crocidolite and amosite are more friable than chrysotile);n the asbestos product (sprayed coating and lagging are more friable and loose
n
n
n
n
n
n
n
n

and crumbly than others);
how the material will be worked on (ie type of tools);
how roughly the material will need to be treated to do the job;
how much of it will be worked on;
how long it will be worked on;
how effective the control measures at source are in reducing the spread of
dust and concentrations of asbestos fibres in air;other available information (eg past exposure monitoring records for similar
circumstances; information in Tables 1.1 and 1.2);
past experience and knowledge which are relevant to the work in question;andan allowance for short-term unexpected high exposures.

RPE should be used to complement controlled stripping techniques
and not in place of them. Uncontrolled removal of asbestos (seeparagraph 7.68) will generate airborne fibre concentrations beyond
the protection provided by any power-assisted respirator

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Box 1.2 Some indicators of high exposure/poor control (this list is not exhaustive)
Work methods■■ During removal, dry patches of insulation are found.
■■ Material in asbestos waste sacks is not doughy, but hard and crumbles whensqueezed through the bag.
■■ Excessive breakage to AIB sheets.
■■ The inner surface of the viewing panel is dusty.
■■ Heavily laden pre-filter on the negative pressure unit (NPU).
■■ Excessive dust/debris on high level surfaces.
■■ Excessive loose waste stored in the enclosure.
■■ Poor standard of equipment on site, (eg non-adjustable wet stripping needles).
■■ Evidence of equipment used incorrectly (eg decontamination unit (DCU) notconnected, insufficient wetting fluid).
Workers■■ Workers with facial stubble (where face fit is important).
■■ Evidence of contamination on transiting workers.
■■ Evidence of contamination on transit/waste routes.
■■ Evidence of contamination in the DCU.
■■ Decontamination time too quick.
Enclosure integrity■■ Enclosure sheeting shows little sign of negative pressure.
■■ Sheeting in poor state (holes, tape lifting etc).
■■ Airlocks in poor state (flaps incorrectly positioned, taped up).
■■ No or insufficient inward movement of air.
■■ Poor set up of controls (eg NPU) next to the airlocks, causing ‘short-circuiting’of air.
■■ Unweighted airlock flaps.
■■ Transit airlock and baglock open at same time.
Air monitoring
1.24 Regulation 18 of the Control of Asbestos at Work Regulations 2002
(CAWR)7 requires the measurement of employee exposure at regular intervals
and where a change occurs that may affect that exposure. This air monitoring isrequired to show:nnthat control measures (eg wet stripping) are effective and being properly used;
andthat the RPE worn is sufficient to provide adequate protection (ie in addition toprimary control measures).

1.25 A strategy should be developed to meet the monitoring purpose identifiedin paragraph 1.24. The monitoring strategy should also ensure that a representative
range of jobs and work methods are examined. Occupational exposures can varyfrom day to day and even throughout a shift. So, the strategy should take accountof the range of circumstances and conditions that can occur, including different
ACMs, work methods, work areas, work duration etc. Air sampling results should
be used to inform and modify the control arrangements, as necessary.
1.26 The air monitoring data should be used to establish employee exposure
records. Monitoring is not required for every job. Sampling data from previous
similar jobs can be used to judge the effectiveness of controls and to decide
whether action levels or control limits are likely to be exceeded. But, where there
is doubt about the expected exposure concentration, the exposure will have to be
confirmed by air monitoring.
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1.27 Monitoring should be carried out using a method approved by the Healthand Safety Commission (eg using methodology described in Asbestos: The
analysts’ guide for sampling, analysis and clearance procedures).8 If there is doubt
about assessing employees’ expected exposure to asbestos fibres, seek help
from an occupational hygienist or a specialist laboratory. To carry out asbestosrelated sampling and analysis, laboratories must be accredited to ISO 17025 by arecognised accreditation body, eg UKAS (the UK Accreditation Service).
1.28 Tables 1.1 and 1.2 provide information on fibre concentrations likely to beexperienced in a range of jobs. The data is only a guide and is not a substitutefor carrying out a proper assessment of the likely exposure concentrations. The
circumstances of each job can vary widely so an individual assessment should be
carried out.
1.29 It is possible to obtain exposures lower than those quoted for controlled
stripping techniques. Specialist contractors should therefore not take these fibre
concentrations as representing the lowest reasonably practicable, but view themas illustrating how exposures can be reduced. Contractors should therefore always
strive to reduce exposure to as low as reasonably practicable.

Good practiceTable 1.1 Well-controlled work with ACMs

Job

Likely fibre concentrations(fibre/ml)

Controlled wet stripping using
manual tools

up to 1 (unless a dry patch is hit or
lagging becomes detached)

Careful removal of whole AIB

up to 3

Drilling AIB with vacuum trace - local
exhaust ventilation (LEV), or shadow
vacuuming (note drilling holes inasbestos should be avoided where
possible)up to 1

Bad practiceTable 1.2 Poorly controlled work with ACMs

Job

Likely fibre concentrations(fibre/ml)

Stripping pipe or vessel lagging –partially wetted or dry areas present

up to 100

Stripping sprayed coatings –partially wetted or dry areas present

around 1000

Drilling AIB without vacuum trace

up to 10

Reciprocating power sawing AIB

up to 20

Hand sawing AIB

5-10

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Measurements have shown that, where controlled stripping
techniques have been used but not correctly applied, they can leadto high airborne fibre concentrations. Poor wetting is often little
better than uncontrolled dry stripping
1.30
n
n
n

Other reasons for carrying out air monitoring include:

stage 3 of the four-stage clearance procedure (see paragraph 7.132);
leak sampling to check the ongoing integrity of the enclosure (see paragraph6.56);
reassurance air sampling after removal work has been completed.

1.31 Further details on air monitoring are provided in Asbestos: The analysts’
guide for sampling, analysis and clearance procedures.8

Legal requirements
1.32 There are several sets of health and safety legislation that directly or
indirectly place duties on employers in relation to asbestos. The main pieces ofgeneral legislation are listed below:nnn

The Health and Safety at Work etc Act 19749 (HSWA) (Section 2)requires an
employer to conduct their work in such a way that their employees will not be
exposed to health and safety risks, and to provide information to other people
about their workplace which might affect their health and safety. Section 3 of
HSWA contains general duties on employers and the self-employed in respectof people other than their own employees. Section 4 contains general duties foranyone who has control, to any extent, over a workplace.
The Management of Health and Safety at Work Regulations 199910 require
employers and self-employed people to make an assessment of the risks to
the health and safety of themselves, their employees, and people not in theiremployment arising out of or in connection with the conduct of their businessand to make appropriate arrangements for protecting those people’s health andsafety.
The Construction (Design and Management) Regulations 1994 (CDM)11
require the client to pass on information about the state or condition of any
premises (including the presence of hazardous materials such as asbestos) tothe planning supervisor before any work begins and to ensure that the healthand safety file is available for inspection by anyone who needs the information.

1.33 There are two sets of specific health and safety regulations that directly
apply to work with asbestos. These are:nn

The Control of Asbestos at Work Regulations 2002;7
The Asbestos (Licensing) Regulations 1983 (as amended) (ASLIC).1

The key requirements of these regulations are outlined below.
The Control of Asbestos at Work Regulations 2002
1.34 CAWR applies to all work with asbestos. It requires employers to prevent
exposure of employees to asbestos or, where this is not reasonably practicable,
to reduce exposure as low as is reasonably practicable. The spread of asbestos
should also be prevented. The key to controlling asbestos exposure and spreadis through a suitable and sufficient risk assessment (RA). Before starting any workwhere asbestos is present, CAWR requires an employer to make an assessment of
the likely exposure of employees to asbestos and to prepare a plan of work (POW).
The assessment and POW should be in writing and should, among other matters,
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include details of the steps that need to be taken to meet the requirements of theregulations.
1.35
n
n
n
n
n
n
n
n
n
n

CAWR also includes requirements on the following:a duty to manage asbestos in non-domestic premises;
notification of work with asbestos;
provision of information, instruction and training;use of control measures;
maintenance of control measures;provision and cleaning of protective clothing;arrangements to deal with accidents, incidents and emergencies;
cleanliness of premises and plant;
air monitoring;
health records and medical surveillance.

1.36 The licensed asbestos removal contractor (LARC) may not always need tomake a new assessment before each individual job if the work involves similar jobs
on a number of sites, eg removing asbestos ceiling tiles from a number of identicalor similar offices. But where the work varies significantly from site to site, a newassessment will need to be made for each job.
1.37 More information on the requirements of CAWR can be found in the
Approved Code of Practice (ACOP), Work with asbestos insulation, asbestos
coating and asbestos insulating board. Control of Asbestos at Work Regulations
2002. Approved Code of Practice and guidance.12
Control limits and action levels
1.38 CAWR also specifies requirements to limit airborne exposure to asbestos:
control limits and action levels. A control limit is that concentration of asbestos
in the air (averaged over any continuous four-hour or ten-minute period) above
which employees must not be exposed to unless they are wearing suitable RPE.
Both the four-hour and ten-minute periods have their own control limits, the valuesof which vary depending on the type of asbestos present. The control limits are
given in Table 1.3 and exposures should be reduced to the lowest level reasonably
practicable below them.
1.39 Action levels apply to exposure in the longer term, and are cumulative
exposures calculated over any continuous 12-week period. The 12-week period
should not be deliberately chosen to avoid exceeding an action level; it should
represent a ‘worst case’ for the work being undertaken. If the exposure of any
employee exceeds or is likely to exceed an action level, the regulations in CAWR
on notification, designated area and medical surveillance, apply. The action levels
are given in Table 1.3. Asbestos: The analysts’ guide for sampling, analysis andclearance procedures8 contains guidance on how to calculate action levels.

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Table 1.3 Control limits and action levels for asbestos

Asbestos type4-hr control limit(f/ml)

10-min control
limit (f/ml)

Action level(fibre hrs/ml2)

Chrystoline alone

0.3

0.9

72

Any other form ofasbestos, either
alone or in
mixtures,including mixturesof chrysotile withany other form ofasbestos

0.2

0.6

48

Notes
f/ml - fibres per millilitre of air averaged over any continuous period.
fibre hours/ml - calculated by multiplying the airborne exposure in f/ml by the time in hours
for which it lasts to give exposure in fibre hours/ml. Cumulative exposures are calculated byadding together all the individual exposures over any continuous 12-week period.

The Asbestos (Licensing) Regulations 1983 (as amended)
1.40 In Great Britain, work on asbestos insulation, asbestos coating and AIB has,by law, to be carried out by a contractor who holds a licence under ASLIC although
there are exceptions, eg where the work is of short duration. Paragraphs 2.2-2.10
provide full details.
1.41 These exclusions mean that maintenance workers do not need alicence to do minor work, eg installing a light fitting, providing the work is
short duration and exposures are unlikely to exceed action levels or control
limits. Although a licence is not required, they should have the necessary
expertise and the work must comply with CAWR. However, if in generalterms, good working practices are followed, compliance with CAWR will
be achieved. HSE has produced guidance for non-licenced work, Asbestos
essentials. There are two publications, Introduction to asbestos essentials:
Comprehensive guidance on working with asbestos in the building maintenanceand allied trades;13 and Asbestos essentials task manual: Task guidance sheets
for the building maintenance and allied trades,2 both available from HSE Books.

Management of asbestos
Is asbestos removal necessary?
1.42 Regulation 4 of CAWR places a duty to manage asbestos in non-domestic
premises. As part of the management of asbestos, ACMs should be maintained ingood condition and only removed if absolutely necessary. ACMs in good conditionand left undisturbed will not release fibres into the air and will not cause exposureand spread. Asbestos should not be removed simply because it is there. It may
also be possible to avoid disturbance of asbestos during maintenance or building
work, eg by routing services through an alternative location.
1.43 The removal of asbestos by its very nature will cause disturbance andspread. Where it is removed, the work must be strictly controlled. Appendices 1.11.4 contain flow charts describing the options for the management of ACMs. Thereare charts for different types of asbestos. The charts work systematically throughthe options and actions for ACMs, depending on the type and condition of thematerial.

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1.44
n
n
n
n
n

Examples where removal will be necessary include:

before the demolition of a building;
before maintenance or refurbishment work which may disturb ACMs;
where ACMs are damaged;
where ACMs are vulnerable to damage by the normal day-to-day activities inthe building;where a change in the use of a building may make ACMs more prone todamage.

Asbestos should only be removed if absolutely necessary
1.45 ACMs should remain in place and be included in a building management
plan. Small areas of damage can be repaired, the material encapsulated or
enclosed by another non-asbestos material.
1.46 	 Appendices 1.1-1.4 summarise the management decisions and actions to
be taken as part of the management process for asbestos in buildings. Further
detailed information on managing asbestos in buildings is given in A comprehensive
guide to managing asbestos in premises.14

Medical examination of asbestos removal workers under CAWR
2002
Status of the medical examination and certificate of examination
1.47 	 Under the current CAWR the medical examination is not a fitness for work
examination. The certificate of examination only contains the information that an
employee has been examined at a certain date (regulation 21, paragraphs
4 a and b). All other statutory medical examinations (for instance for lead, ionisingradiation and diving) conclude with a fitness for work judgement. This approachin the CAWR medical examination is unusual and has historical reasons. As aconsequence, the medical examination does not certify that the employee isnecessarily fit for all work conditions that can be present in an asbestos enclosure.
This current position may change at the next review of CAWR, due in 2006.
Risk assessment of the work conditions
1.48 	 The employer has to assess any specific hazards and risks in their RA as
required by regulation 3 of the Management of Health and Safety at Work Regulations
1999.10 Such factors may include working with RPE or working at height withthe risk of falling. Depending on the conditions inside the enclosure, for instancewhen work in hot conditions cannot be avoided, an asbestos enclosure may also
become a confined space, as defined in the Confined Spaces Regulations 1997.15
If that is the case, the competent person carrying out the RA for work in confined
spaces may need to consider the suitability of individuals for that work. This may,eg require checking whether the individuals are of a suitable build and stamina. If in
doubt, but especially in the case of unavoidable hot work or the necessity to wear
breathing apparatus, competent medical advice on an individual’s suitability for
the work may be needed and therefore an additional fitness for work examination,in addition to the CAWR medical examination, may be required (see Work withasbestos insulation, asbestos coating and asbestos insulating board. Control ofAsbestos at Work Regulations 2002. Approved Code of Practice and guidance,
paragraph 79).12
1.49 	 Considering the fitness for work of the operatives is always good practice,even if the strict definition of a confined space does not apply. In particular, where
any medical condition could interfere with the correct use of personal or respiratory
protective equipment, an operative is prone to sudden loss of consciousness or
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has significant sickness absence, an assessment by a competent person could
be needed. Examples of such medical conditions are heart and lung (for instanceasthma) diseases, unstable diabetes mellitus, epilepsy, claustrophobia (fear ofsmall spaces), mental conditions or the taking of certain medications. Simple
questionnaires, preferably administered by an occupational nurse, can help
introduce additional safety with minimal effort. Final judgement on fitness for workin case of detection of medical anomalies should be reserved for an occupational
physician with good knowledge of the specific work requirements and work
conditions present in an asbestos enclosure.
When is a medical required?
1.50 	 A medical examination is required when the exposure of an employee could
exceed the action level for asbestos fibres. The action level is an amount of fibres
per millilitre of air as measured over a 12-week period (see paragraph 1.39). The
Regulations currently give different action levels for chrysotile asbestos and othertypes of asbestos, although in reality, most asbestos removal workers work with all
types of asbestos and for simplicity use the control limits/action levels for amosite/
crocidolite. Because the action level is measured over a period of time and also
depends on the type of asbestos being worked with, the question whether theaction level will be exceeded depends on the pattern of work and the RA for eachjob. The employer is responsible for this RA and therefore also for determining
whether the employee might exceed the action limit. Most removal worker
exposure will exceed the action level.
How often is the medical examination carried out?
1.51 	 When work with asbestos starts under conditions that will exceed theaction level, employees need to be under medical surveillance. For the purposeof the Regulations it is however sufficient if the employees and the employer haveobtained a valid certificate of examination, which is not older than two years, before
the work starts. After the first examination the medical examination is repeatedat intervals of no longer than two years (or at a shorter interval as decided by thedoctor who carries out the examination), for as long as the employee is likely to be
exposed over the action level.
The purpose of the examination
1.52 	 Asbestos in all its forms is a very hazardous material. It can cause serious
lung disease such as asbestosis and different forms of lung and other cancers(mainly malignant mesothelioma (see paragraphs 1.12-1.19). From past experience
we know that under the current exposure situations the biggest risk to health is still
the risk of cancer.
1.53 The medical examination is part of the strict control measures necessary tohelp ensure that people who work with asbestos do so in a safe way. The main aimof the examination is to advise the employees about the potential health risks ofasbestos and of their fitness for work. The latter is however not communicated tothe employer in the certificate of examination. Although the examination is looking
for signs of ill health, possibly linked with asbestos exposure, it is important toknow that it may take many years before signs of ill health from past asbestos
exposure become detectable by the examination. Therefore the other important
purpose of the examination is to provide the employee with the opportunity to
speak to a medical doctor about any concerns they may have regarding their work
and/or their health.
Who carries out the medical examination?
1.54 	 Medical examinations under CAWR are carried out either by an employment
medical advisor working for HSE or by an appointed doctor. In practice, anappointed doctor will almost always carry out the examination. Appointed doctors
are appointed by the Employment Medical Advisory Service (EMAS) of HSE andAsbestos: The licensed contractor’s guide

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act as an agent on behalf of EMAS. EMAS provides guidance for the appointed
doctors, as well as conducting regular checks to control the quality of their workand their medical documentation.
The content of the medical examination
1.55 	 The Regulations require the doctor to perform at least a specific examinationof the chest. EMAS guidance will provide the appointed doctor with advice about
the content of the examination. Usually the examination will include taking or
updating a work history and questions about general health and the health ofthe lung. The doctor will perform a clinical examination of the chest and look forother signs of respiratory disease as well as carrying out a lung function test. A
chest X-ray is not part of the examination on a routine basis. The reason for thisis that the doctor is obliged by law to make an assessment of the benefit in eachindividual case of any chest X-ray examination, bearing in mind that all ionisingradiation (X-rays) carry a small health risk. If the doctor has reason to believe thata chest X-ray would be useful on clinical grounds then it may be ordered as partof the examination. It is important to remember that an ‘all-clear’ chest X-ray does
not mean that the current working methods are safe because it takes many years(usually more than 15-20) before a chest X-ray will show any signs of past asbestos
exposure.
Certificate of examination
1.56 	 After the examination the appointed doctor will issue the employee andthe employer both with an original certificate of examination. This is to reduce thechance of forgery of certificates.
1.57 	 This certificate only indicates that the examination under the requirementsof CAWR has been carried out and includes the date of the examination. It does
not certify any fitness to work with asbestos. This is because the appointed doctor
is unable under the Regulations to declare someone unfit for work with asbestos.
The appointed doctor does however have an obligation to advise the employee
if they think the employee is not fit to start work with asbestos or in their opinion
should stop working with asbestos. In exceptional circumstances, where someone
is clearly a danger to themselves and possibly others, the appointed doctor may
consider informing the employer about the employee’s condition. Usually theappointed doctor will however ask for informed consent before disclosing any
medical in confidence information to the employer.

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Appendix 1.1 Materials identified as containing asbestos

No

Does the material
contain asbestos?

Yes

Is the material ingood condition?

Yes

No

Is the material
spray or pipe lagging?

Yes

See Appendix 1.2

Yes

See Appendix 1.3

Yes

See Appendix 1.4

No

Is the material
insulating board
or blocks?

No

Other asbestos
material

Record non-asbestos
material

Record, manage
and monitor

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Appendix 1.2 Sprayed asbestos coatings and pipe and vessel insulation in poor condition

Is the material
readily repairable?

Yes

Carry out repair workNo

Is the material
accessible?
See Note 1

No

Yes

Is the damage
extensive?
See Note 3

Is the damage
extensive?
See Note 2

No

Yes
No

Yes

Is there loose
friable material?
See Note 4No

Seal orencapsulate

Yes

EncloseYes

Is enclosure
feasible?

No

RemoveRecord, manage
and monitor

Notes
1 Is the material accessible and vulnerable to further accidental or deliberate damage from adjacent repair or maintenance,
impact by people, vehicles, objects or vandalism?
2 If the damage is slight and the ACM is not easily accessible, remedial work is unlikely to be necessary. The damage
should be monitored and your decision reviewed if circumstances change (eg the area becomes accessible)
3 If the damage is superficial, eg slight cracking to pipework insulation or deteriorated surface finish, then answer ‘no’to this question. If, eg the insulation is starting to come away from the pipework or the spray coating appears to 		be loose in places, then answer ‘yes’ to this question. If there is debris on the floor or other surfaces then this will needremoving following appropriate precautions.
4 The damage may be extensive, but if the material is generally sound without friable material or loose pieces, then 		sealing/encapsulation may be possible.

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Appendix 1.3 AIB and insulating blocks in poor condition

Is the material
readily repairable?

Yes

Carry out repair workNo

Is the material
readily accessible?
See Note 1

No

Yes

Is the damage
extensive? See Notes 2
and 3

No

Yes

Is sealing or
enclosure feasible?

Yes

Seal orencloseNo

RemoveRecord, manage
and monitor

Notes
1 Is the material accessible and vulnerable to further accidental or deliberate damage from adjacent repair or maintenance,
impact by people, vehicles, objects or vandalism? If the damage is not easily accessible, remedial work may not be 		
necessary. The damage should be monitored and your decision reviewed if circumstances change (eg the area becomes
accessible).
2 If the damage is superficial, eg slight cracking to pipework insulation or deteriorated surface finish, answer ‘no’ to thisquestion. If, for example, the insulation is starting to come away from the pipework or the spray coating appears to beloose in places, answer ‘yes’ to this question.
3 If there is debris on the floor or other surfaces, this will need removing following appropriate precautions.

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Appendix 1.4 Other asbestos materials in poor condition (read Notes 1 and 2 first)

Is the material
readily repairable?

Yes

Carry out repair workNo

Is the material
accessible?
See Note 3

No

Yes

Is the damage
extensive?
See Note 4

No

Yes

Is sealing or
enclosure feasible?

Yes

Seal or enclose

No

RemoveRecord, manage
and monitor

Notes
1 This chart covers products not included in Appendices 1.2 and 1.3 such as asbestos cement, textiles, gaskets, ropes
and encapsulated products such as vinyl and thermoplastic tiles, roofing felts etc. Materials which are encapsulated
in a resilient matrix will have limited ability to release fibres, therefore asbestos in reinforced plastics, vinyls, resins,
rubber, mastics, bitumen, paints, flexible plasters and cements have little opportunity to release fibres unless the matrix
is removed (eg degraded, dissolved or burnt) or subject to high levels of abrasion (eg use of power tools). Managementof these types of materials so maintenance workers do not use abrasive methods and power tools is usually sufficient
to minimise airborne asbestos releases. Sealing may be considered if there is evidence of routine wear and abrasion.
The flow chart shows you the decisions to consider if remedial action is deemed to be necessary. However, unless thedamage is significant or they are in a vulnerable position, urgent remedial action is unlikely to be necessary and you
should simply remove these products, following the correct precautions when they come to the end of their useful life, or
before refurbishment or demolition.
2 Products which are less well encapsulated (eg asbestos textiles and gaskets), will release fibres more readily and use ofcontrolled work methods by maintenance workers and enclosure or sealing to prevent damage may be necessary insome circumstances.
3 Is the material accessible and vulnerable to further accidental or deliberate damage from adjacent repair or maintenance,
impact by people, vehicles, objects or vandalism?
4 If the damage is slight, remedial work is unlikely to be necessary. The damage should be monitored and your decision
reviewed if circumstances change (eg the area becomes accessible).
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Appendix 1.5 Further information
This guidance will help you to assess and control occupational exposure toasbestos, but you may need to seek advice and expertise from other sources.
These include:
n

n
n
n
n

trade associations, who can provide advice on current practice, technologicaldevelopments etc. For example:
–
ACAD;
–
ARCA;
your local HSE office or HSE’s Infoline;
your equipment supplier;
your personal protective equipment (PPE) supplier;occupational hygienists/safety consultants can provide advice on theassessment and control of exposure to asbestos. If you decide to employ theservices of a consultancy, you should ensure that they are competent to carryout the work. One way to do this is to use one that is a member of BOHS/
ATAC.

ACAD:
Asbestos Control and Abatement Division
TICA House
Allington Way
Yarm Road Business Park
Darlington
Co Durham
DL1 4QB		
Tel: 01325 466704
www.tica-acad.co.uk
ARCA:
Asbestos Removal Contractors Association
ARCA House
237 Branston Road
Burton upon Trent
Staffordshire
DE14 3BT
Tel: 01283 531126
www.arcaweb.org.uk
BOHS:
British Occupational Hygiene Society
5/6 Melbourne Business Court
Millennium Way
Pride Park
Derby
DE24 8LZ
Tel: 01332 298101
www.bohs.org

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ATAC:
Asbestos Testing and Consulting
237 Branston Road
Burton upon Trent
Staffordshire
DE14 3BT
Tel: 01283 531126
www.arcaweb.org.uk
HSE Infoline:
Tel: 0845 345 0055
Fax: 0845 408 9566
Textphone: 0845 408 9577
e-mail: hse.infoline@natbrit.com

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Chapter 2: Licences for workwith ACMs

Summarynnnnn

A licence is required for work on asbestos, unless one of the exemptions
applies.
There are three categories of work which require a licence: full, supervisory andancillary.
Licence application packs can be obtained from HSE’s Asbestos Licensing Unit
(ALU).
Strict controls are placed on hiring employees for work with ACMs.

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Contents
Introduction 30
Licences for work with ACMs

30

When is a licence required? 30
Types of licence 32
How to obtain a licence 33
Enforcing authority site visits 34
Liaison with the asbestos industry 35

Hiring employees

35

Hiring removal operatives from another company 35

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Introduction
2.1
Disturbance of certain types of asbestos products can give rise to significant
health risks. Therefore, as part of health and safety legislation, the law requiresthat work with the most hazardous forms of asbestos can only be carried out bycompanies who have obtained a licence for such work from HSE (there are minor
exceptions to this). This licensing regime is a key component in the arrangements toensure the highest standards of asbestos control and protection for workers and the
public. This chapter explains the licensing system.

Licences for work with ACMs
When is a licence required?
2.2
ASLIC prohibits work with certain types of asbestos materials, namely
asbestos insulation, asbestos coating or AIB, except in specific circumstances(see paragraph 2.4), unless it is carried out by an employer or a self-employedperson who holds a licence granted by HSE. Under powers delegated from
HSE, the ALU may grant a licence for work with these materials if it considers it
appropriate to do so.
2.3 	 Under ASLIC, work with asbestos means work in which asbestos insulation,asbestos coating or AIB is removed, repaired or disturbed and includes work in asupervisory or ancillary capacity (see ASLIC, paragraphs 16-17).1
2.4 	 There are three occasions when a licence to work with asbestos insulation,asbestos coating or AIB is not required. These are:nnn

for work of short duration (this is where the total number of hours worked is
not longer than one hour in seven consecutive days for any one person andthe total time spent by all the workers is no more than two hours, also in sevenconsecutive days);
for air monitoring or sample collection to identify asbestos; orif you are an employer carrying out the work with your own employees on yourown premises (Note: in such circumstances notification to the appropriate
enforcing authority is required under regulation 5 of ASLIC).

Irrespective of whether the work is licensable or not, any work withasbestos must comply with CAWR
Short duration work
2.5 	 All companies, whether licensed or not, may carry out work of shortduration, provided they possess the necessary expertise. The exemption applies
to individual tasks, where the specified time periods in paragraph 2.4 are notexceeded. However, those individuals cannot then do any more unlicensed shortduration work for seven days and the employer must be able to show that they
have a system of controlling this work, recording times, notifying managers, etc.
The time calculation includes:nnnany preparatory work, such as sheeting of the floor, segregating the work area,or any other activity involved in preparing the work;
the actual work on the asbestos; andany activities once the actual work on the asbestos has been completed, suchas cleaning up.

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Products excluded from the licensing regulations
2.6 	 There are certain asbestos products to which ASLIC does not apply. ASLIC
does not apply to:nnn

asbestos cement (see Figure 2.1), defined as material which is mainly a mixtureof cement and asbestos and which when in a dry state has a density greaterthan 1 tonne per cubic metre. This material is typically found as roofing sheets,
gutters, cladding, drainpipes, flues and some soffits;
articles made of rubber, plastic, resin or bitumen but which also containasbestos (eg vinyl floor tiles, electric cables and roofing felts); or
other asbestos products which may be used at high temperature but have noinsulation purposes, such as gaskets, washers, ropes and seals.

Figure 2.1 Non-licensable products

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Figure 2.2 Removal work

Types of licence
2.7
There are three categories of work requiring a licence – full repair andremoval work, supervising work and ancillary work (but also see paragraph 2.10).
nnnFigure 2.3­  Supervisory
licence holder checking the
integrity of an enclosure

A ‘full’ licence is required to remove, repair or disturb asbestos insulation orasbestos coating or AIB (see Figure 2.2).
A ‘supervisory’ licence is required for those involved in direct supervisory
control over asbestos work being undertaken by another licensed contractor(see Figure 2.3). Direct supervisory control is taken to mean where there isdirect and immediate influence over current site activities involving any aspectof the work with asbestos, including the equipment and controls being used;
how the work is done (methods); how the site is prepared, cleaned up etc; themonitoring of controls (eg inspecting DCUs, changing filters etc); andmovement, storage and transfer of waste.
An ‘ancillary’ licence is needed to carry out work associated with the main
work of repair, removal or
disturbance of asbestos insulation, asbestos
coating or AIB.

Examples where an ancillary licence is needed include:nnnFigure 2.4­  Scaffolding
work

the erection or dismantling of enclosures for licensable asbestos work;
the maintenance and servicing of certain types of equipment (eg NPUs) on
site;
the erection, altering, maintenance, or dismantling of scaffolding which forms
the key part of the framework or the overall support from which an enclosure
will be built for licensable asbestos work, or if the scaffolding provides accessfor work on asbestos (or otherwise) where it is foreseeable that asbestos islikely to be disturbed by the scaffolding activity (see Figure 2.4).

2.8
All licences contain standard conditions and some may have additional
conditions. Supervisory and ancillary licences each contain an additional
condition, which limits the work of the licence holder to that activity. The standard
conditions are summarised in Box 2.1.
2.9
Licences are usually granted to work with all three forms of licensable
asbestos material. Depending on the type of work undertaken this may not beappropriate and the licence will be limited to those licensable asbestos materials
the applicant is competent to work with, eg a specific licence for AIB or decorative
coating.
2.10 	 Licences are also granted to organisations who do not undertake work
themselves, but act as ‘recruitment agencies’, supplying labour to other licenceholders. These licences restrict the activity of the licence holder to hiring out trainedand equipped operatives to do work that is supervised and managed by otherlicence holders.

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Box 2.1 Summary of standard licence conditions
1 The licence (or a copy) should be made available to those who need to see it,
eg potential clients at tendering, inspectors. A copy of the licence should
accompany each notification of asbestos work and a copy should be available
on site.
2 The licensee should give written notice (at least 14 days or other agreed
period in advance) to the relevant enforcing authority of each asbestos job.
The notice should specify:■■ the type and likely duration of the work;■■ the address of the premises involved;■■ the starting date.

The enforcing authority must also be informed in writing immediately if thisinformation changes.
3 The notice of work required by condition 2 shall include:■■ a suitable and sufficient written method statement for the work;■■ suitable and sufficient written details of the control measures (including RPE

and personal protective equipment (PPE)) and decontamination procedures forthe asbestos workers.
How to obtain a licence
2.11 For HSE to be able to consider granting a licence, the applicant must:
n

n
n
n

intend to do work with asbestos insulation, asbestos coating or AIB (HSEdoes not grant licences to applicants who do not intend to work withasbestos but who have only applied for ‘commercial’ reasons);
have at least one or more competent individual(s) within the organisation, whowill have lead responsibility for asbestos work;
have a written policy and organisational arrangements which will satisfy therequirements of CAWR; andbe clear about the type of licence (ie full, supervisory or ancillary) that would
be appropriate for their business and for which their organisation has thenecessary competence.

2.12 An application pack, comprising explanatory notes, an application form FOD
ASB1, a list of reading material and a list of training organisations, is available directfrom the Asbestos Licensing Unit, Health and Safety Executive, Belford House,
59 Belford Road, Edinburgh EH4 3UE Tel: 0131 247 2135. Existing licence holders
are automatically sent an application pack a few months before the expiry of theircurrent licence.
2.13 The FOD ASB1 is a general form for all licence applications. It must becompleted and sent to ALU at least 28 days before the date from which the licenceis to run, together with the current fee.
2.14 On receipt of the completed application form and fee, the details arechecked by ALU and the form is sent to the Asbestos Licensing Principal Inspector(ALPI), based at the applicant’s local HSE office. Arrangements are then made for
the ALPI or one of their inspectors to assess the applicant’s capability to work withasbestos insulation, asbestos coating or AIB.

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2.15 Every applicant will be formally assessed on all aspects of managing andworking with ACMs. The assessment will include knowledge of asbestos andasbestos requirements, practical aspects of the work, management policies,
systems and record-keeping arrangements.
2.16 A good understanding of the standards expected together with adequate
arrangements for meeting these standards is essential for making a successful
application. In some cases, an applicant (eg managing director) may not have thedetailed knowledge of asbestos requirements, as this may have been delegatedto other employees within the firm. In such cases, it would be expected that acompetent person responsible for asbestos operations within the organisation
would be present at the assessment together with a director or partner. If theapplicant (and the responsible person, if required) were not fully conversant withthese requirements, it would be unlikely that the application would be successful.
2.17 Part of the assessment concentrates on practical matters including training,
medical certification, RPE and equipment such as NPUs and DCUs. Whether theapplication is for a full, supervisory or ancillary licence, the assessment will cover
the same topics but to varying degrees. For example, an applicant for an ancillary
licence to do scaffolding work associated with asbestos removal, would not be
expected to have detailed knowledge of asbestos removal techniques and theequipment requirements for this work.
2.18 Following the assessment, a report is completed by the inspector andis submitted together with recommendations to ALU. Successful applicants are
granted a licence either for one year (new applicants are granted a one-year
licence) or three years. Most renewal applicants graduate to a three-year licence,but some are renewed for a shorter period. One or two-year renewed licences may
be given for the following reasons:
n
n
n
n
n

the applicant’s performance has caused concern;a failure to maintain competence;
keeping inadequate records or by allowing training to lapse;
not having done any work in the previous licence period;change of management.

2.19 Unsuccessful applicants are informed by ALU of the reasons for refusing
their application and are usually given four months to rectify matters and bereassessed, should they wish to proceed. There is a charge for reassessments.
Enforcing authority site visits
2.20 All licence holders are required as a condition of their licence to notify theenforcing authority (either HSE or the local authority) with details of the proposed
work at least 14 days before it is due to start. Separate notification is required for
all licensed organisations on the same job.
2.21 This condition gives the enforcing authorities the opportunity to assess
the proposals contained in the licence holder’s POW, which forms part of thenotification, and to inspect the site either before or during the work.
2.22 Licence holders in certain categories are more likely to receive
proportionately more site visits from HSE. These categories include:nnn

new one-year licence holders;
three-year licence holders whose licence expires in four to six months andwho have not been visited in the previous twelve months;
licence holders whose past performance has given cause for concern;

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Executivenlicence holders who have proposed a work method which raises concerns (egproposals to carry out uncontrolled dry stripping, unjustified use of a power
tool or to work in close proximity to hot surfaces).

2.23 Reports of inspectors’ visits to licensed asbestos work are submitted to
ALU, who review the licence holder’s performance accordingly. If adverse reports
are received, this may result in action being taken against the licence holder, eg
their licence may be amended (by having further conditions added or by having
the licence term reduced), or they may be refused a licence on application or the
licence may be revoked. This may be in addition to any enforcement action thatmight be taken by the local inspector(s) who carried out the site inspection, eg theinspector may issue a Prohibition Notice on the contractor where site conditions
indicate a risk of serious personal injury if the work continues without further
controls. This is a formal step to stop the work until HSE can be sure the work canproceed safely.
Liaison with the asbestos industry
2.24 In 2000, HSE established an industry liaison forum, the Asbestos Liaison
Group (ALG), comprising members from the main asbestos trade associations,trade unions and HSE. ALG provides a forum to promote quality standards, bestpractice and consistency of approach in relation to control and work with asbestos
across Great Britain. It meets regularly and is also responsible for producing jointly
prepared guidance notes (ALG memos) to address issues of concern. The memos
are available on the HSE website at www.hse.gov.uk/aboutus/meetings/alg/index.
htm.

Hiring employees
2.25 From time to time, licence holders may need to hire temporary personnel
to supplement labour. In such circumstances, to comply with ASLIC, the licenceholder must either recruit directly, or hire personnel from other licence holders(ie another licensed asbestos removal contractor), or from a company with anasbestos licence from HSE to supply labour. Standards of site control should bemaintained in such circumstances.
2.26 Organisations in the third category do not undertake work themselves but
act as ‘recruitment agencies’ supplying labour to other licence holders. Theselicences contain specific conditions restricting the activity of the licence holder tohiring out trained and equipped operatives, who hold current certificates for medical
examinations and RPE face-fit testing, to do work that is organised and managedby other licence holders.
Hiring removal operatives from another company
Licence holders who undertake work in their own right and supply labour
2.27 Licence holders may supply their employees (ie operatives) to work under
the supervision of other licensed contractors (these employees will not act in asupervisory or management capacity, but see paragraph 2.34). Licence holders’
responsibilities in these circumstances are set out in Box 2.2. If the licence holder
supplies labour infrequently (eg less than once a month), then they are not required
to notify the enforcing authority about this.
2.28 If the licence holder regularly supplies labour (eg at least once a month) thenthey must inform the Head Office ALPI every three months in arrears. The licenceholder will consequently have a further licence condition added regarding hiring.

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2.29 Licence holders who hire in labour must record exposure levels for theperiod during which the temporary staff have worked for them and provide thisinformation to the licence holder who supplied the labour. The licence holder
supplying the labour must ensure that they obtain this information to complete
their employees’ exposure records, making sure that there are no gaps in the
documentation.
Licence holders (‘recruitment agencies’) who supply labour but undertake nowork in their own right2.30 Organisations who hold a licence to supply labour, but who do not actually
undertake work themselves are not permitted to supply personnel to supervise or
manage the work being undertaken by other licence holders. The asbestos licensed
contractor actually doing the work is responsible for supervising and managing it.
2.31 Licence holders in this category are required to notify details of theiremployees, their hire contacts etc, as specified in their licence condition, to the
Head Office ALPI every three months in arrears.
2.32 This licence holder must also obtain the exposure records for theiremployees while their employees were working for other licence holders. They mustretain the records for 40 years.
Box 2.2 Licence holders who supply labour (main points)
All licence holders in this category will be responsible for:■■ their employees’ training (including refresher), medical surveillance, face-fit

testing, RPE provision and maintenance of ongoing health records;■■ only supplying their employees to work under the supervision of anotherlicensed contractor;■■ providing the licence holder, who has hired in the labour, with face-fit,

medical, training etc records for their employees for the purposes of on-site
documentation;■■ obtaining exposure records for their employees during the periods of the hire;■■ notifying the Head Office ALPI every three months of their contracts (this is
not required if the licence holder supplies labour on an infrequent basis, seeparagraph 2.27).

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Licence holders who actually do the work and hire in labour
2.33 Licence holders in this category will be responsible for:
n
n
n
n
n
n

n

the POW and equipment specification;
all plant and equipment;
supervising, managing and being responsible for work practices/work on site;
supplying PPE for employees, including hired personnel (the licence holder
supplying the labour will provide their employees with their own RPE);
notifying the work (on an ASB5) to the enforcing authority;
checking that the hired employees have been trained successfully, face-fit
tested for RPE and have undergone a medical etc. Copies of these records
should be kept with other site documentation;
recording exposure levels for the hired employees and ensuring thisinformation is provided to the licence holder who supplied the labour, formaintenance of health surveillance records.

Supplying supervisory or management personnel
2.34 If a licence holder supplies an employee to work in a supervisory or
management capacity for another licence holder, then both licence holders are
deemed to have responsibility for the work. In such situations, both companies
are required to notify the enforcing authority at least 14 days before work begins.
Organisations who hold restricted licences and act as ‘recruitment agencies’ areonly permitted to supply personnel at operative level (see paragraph 2.30).

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Chapter 3: Risk assessments,
plans of work and notifications
for work with ACMs

Summarynnn

Risk assessments:– should identify all the risks associated with the asbestos work;– should be carried out by a competent person;– should describe the work, the expected exposures and methods of control.
Plans of work:– should include the site-specific details of the work (scope, removal methods,
all procedures and arrangements for smoke testing, air monitoring etc);– should include a detailed diagram of the location of the work routes;– should be made available to employees, others involved in the work and theanalyst.
Notifications and waivers:– should be made to the enforcing authority, 14 days before work is due tostart;– waivers, permitting an earlier start date, are only given for genuine
emergencies.

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Contents
Introduction

40

What is the difference between an RA and a POW? 40

Risk assessments

40

Why are RAs needed and when should they be done? 40
Who should do the RA? 40
What should an RA cover? 41
What should be recorded? 42
When should assessments be reviewed? 43

Plans of work43

Why are POWs needed? 43
What does the ACOP say should be included in a POW? 43
What does this mean in practice? 44
What should be considered in POWs by full licence holders? 45
What should be considered in POWs by supervisory licence holders? 46
What should be considered in POWs by ancillary licence holders? 47
When and why do POWs have to be provided to enforcing authorities? 48
When should POWs be reviewed? 48

Notifications and waivers

48

Paperwork required on site

50

Notifications 48
Waivers 49

For the contract 50
For the equipment 51
For your employees 51

Appendix 3.1: ASB5 notification
Appendix 3.2: Site diagram

52

53

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Introduction
3.1
This chapter covers RAs, POWs and notifications for licensable work withasbestos insulation, asbestos coatings and AIB.
What is the difference between an RA and a POW?
3.2
An RA is the process the employer undertakes to establish all the risks
associated with the asbestos work and the precautions needed to prevent or
minimise those risks. The POW or method statement is specific to a particularjob. Its purpose is to provide a practical document, which summarises the key
control measures resulting from the RA. These measures are based on the specificfeatures of a particular location and the work involved. The POW is intended todirect the work of the asbestos removal team (including the analyst).
3.3
There is clear overlap between the content of the RA and the content of
the POW. It is therefore acceptable where such overlaps occur, that information is
not repeated. POWs will often contain material that under the following guidance isreferred to as part of the RA.

Risk assessments
Why are risk assessments needed and when should they be done?
3.4
Regulation 6 of CAWR requires employers to undertake a suitable andsufficient RA before carrying out any work which is liable to expose their employees(and others who may be affected by the work) to asbestos.

The RA should ensure that all potential risks to health are
fully considered
3.5
The RA ensures that the scope of the proposed works is properly
considered, so the potential risks can be fully established. This will help identify
appropriate work methods, so exposure to asbestos can be adequately controlled
and legal obligations satisfied. For this reason, it should be done in time to allow
for compliance with all the relevant regulations and to enable the appropriate
precautions to be taken before work begins. The assessment process can also
be assisted by involving employees. Workers are extremely well-placed to identify
problems and issues and can assess the practical implications of work methods
and control systems. They will be able to assist in the development of effective andworkable risk control measures.
Who should do the RA?
3.6
The RA must be done by a competent person who should:
n
n
n
n
n
n
n

have adequate knowledge, training and expertise in understanding the risks
from asbestos;know how the work activity may disturb asbestos;know what precautions should be taken to minimise exposure to asbestos;be familiar with and understand the requirements of CAWR and theappropriate Approved Codes of Practice;
have the ability and the authority to collate all the necessary, relevant
information;
have the knowledge, skills and experience to make informed decisions about
the risks and precautions that are needed; andbe able to assess non-asbestos risks on site.

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What should an RA cover?
3.7
The RA should identify all the risks associated with the asbestos work.
Guidance on what the RA should include is set out in paragraphs 3.7-3.13. The RA
should include:nnna description of the work (eg repair, removal, encapsulation of ACM or
maintenance and testing of plant and equipment contaminated with ACMs)
and a note of the scale and expected duration of the work;
details of either the type of asbestos and the results of any analysis, or astatement that the asbestos is not chrysotile alone, so that the stricter actionlevels and control limits apply;
the quantity, extent, condition, thickness and type of ACM, including how it isfixed or attached to substrates.

3.8
The items listed in paragraph 3.7 cover specific matters (such as the work
activity, and the asbestos product and type (including condition)), so that theappropriate control regime can be implemented. It is essential to establish theasbestos product to confirm that the licensing regulations apply. It is also importantto have information on the physical status of the ACM. Knowing the condition
and thickness is particularly relevant to establish the finer details of the removal
method, eg the type and shape of wet injection needles to be used, and if any
preparation work is required (such as pre-drilling or arrangements to attach needles
or the need for a coating). Also knowing how the ACM is attached or fixed to theadjoining material (glued, nailed, screwed, or a combination), is important to ensurethat the removal steps can be properly planned and the most appropriate removal
technique or combination of techniques are used.
3.9
In addition, having information on the material size and location (eg its lengthand span, whether it extends into other rooms and work areas) is important. Itmeans the number of enclosures required, and the necessary arrangements for thetransfer of waste, can be properly assessed. The extent of any overspray, debris
or other contamination beyond the actual ACM should also be established. This
information will help to avoid any confusion over the work being done and which
ACMs will remain in place.
3.10
n

n

n

The assessment should also include:

details of expected exposures, noting:– whether they are liable to exceed a control limit or an action level and thenumber of people likely to be affected;– the level of the expected exposure, so that suitable RPE can be assessedand selected;– whether anyone other than employees may be exposed, and their expected
exposures;– whether intermittent higher exposures may arise; and– results already available from air monitoring in similar circumstances;
the steps to be taken to control exposure to the lowest level reasonably
practicable, eg the type of controlled wetting and method of application, theuse of local exhaust ventilation (LEV) (eg shadow vacuuming), glovebags andwrap-and-cut;
the reasons for the chosen work method. Full justification is required if work
removing coating, lagging and AIB is planned to be carried out:
– dry; and/or– in hot conditions; and/or– using abrasive power tools that impact material.

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Except under exceptional circumstances dry work, hot work
and work using power tools is not acceptable and must not
be carried out
3.11 Hot work is to be avoided where possible. It introduces heat stress risks,
which are extremely difficult to manage, and it can lead to deterioration in asbestos
control. It will only be permitted in exceptional and fully justifiable circumstances.
Hot work is discussed in paragraphs 7.72-7.80. The thermal risks from hot working
should be assessed under other regulations (see paragraph 3.13).
3.12
n

n
n
n

n
n
n

n

Also included in the RA should be:

the steps taken to control the release of asbestos into the environment, eg:– enclosures and negative pressure;– where an enclosure is not planned (ie the RA shows an enclosure to beunnecessary), including when wrap-and-cut and glovebags are being
proposed, a full justification is required on how the potential spread ofasbestos is to be prevented, including arrangements for segregation;– decontamination procedures.
procedures for the removal of waste and contaminated tools and equipmentfrom the work area and the site;
procedures for the selection, provision, use and decontamination of PPE,
which includes RPE;
the arrangements to ensure the premises or parts of premises where the work
has taken place are left clean and safe for reoccupation. These should
include:– details of the areas where clearance certification will be sought;– consideration of potential problems for clearance certification, eg earth
floors, limpet spray ingrained in concrete or tar-like layers, wet areas whichcannot be dried out and the presence of ACMs which are intended toremain in the areas after the work is complete;– consideration of the need for pre-cleaning (often required before setting up
any enclosure);
procedures for dealing with emergencies, including, eg those associated withwork in confined spaces;
the results of relevant medical surveillance;
any other information relevant to safe working such as other significant nonasbestos hazards like working at heights or in confined spaces (see paragraph3.13);
any additional information that may be needed to complete the RA.

The RA should also include non-asbestos risks such as falls fromheight or work in confined spaces
3.13 Depending on the work involved, employers may also have duties underother sets of regulations to carry out a separate RA. For instance, if employees arelikely to be exposed to other risks such as falls from height, confined spaces or
hot conditions, assessments will be required under the Management of Health and
Safety at Work Regulations 1999.10 The results of these RAs should be forwarded
to all interested parties, eg the analyst.
What should be recorded?
3.14 The significant findings of the RA should be recorded in writing and should
form the basis of the POW (see paragraphs 3.17-3.31). All of the findings fromparagraphs 3.7, 3.10 and 3.12 are deemed to be significant. A copy of thesignificant findings of the assessment should be kept readily available on site forthe duration of the work to which they relate; in practice the significant findings willoften end up as part of the POW.
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When should assessments be reviewed?
3.15 Employers should promptly review assessments when there is any reason tosuspect they are no longer valid, where there is a significant change in the work towhich the assessment relates, or when the results of any air monitoring or medical
surveillance show a review is necessary. Any changes to the assessment (andpotentially the POW, see paragraph 3.31) should then be made as appropriate.

Plans of work
Why are POWs needed?
3.16
Regulation 7 of CAWR requires that an employer prepare a suitable written
POW before any work with asbestos is undertaken. The RA is a vital first step toinform the POW (see paragraph 3.2).
3.17 The purpose of the POW (often called a method statement) is to provide
a practical document, which details the specific work methods and control
measures for a particular job at a particular location. The document directs thework and is a source of reference for the asbestos removal team. The POW is anactive document and if any significant changes on site are necessary, it should be
amended and the changes communicated to the employees. The changes should
also be notified in writing to the enforcing authority.
3.18 Employers must make sure their employees follow the POW so far as it isreasonably practicable to do so. If the work cannot be carried out in accordancewith the plan, it must be stopped and the risks reassessed. Work should not start
until a new POW is drawn up or until the existing plan is amended.
What does the ACOP say should be included in a POW?
3.19 Paragraph 35 of Work with asbestos insulation, asbestos coating andasbestos insulating board. Control of Asbestos at Work Regulations 2002.
Approved Code of Practice and guidance12 states that the POW should be sitespecific and should cover in sufficient detail the following information:
n
n
n

n

the scope of the work as identified by the RA (see paragraph 3.7);
the address and location where the work is to be carried out;
the methods to be used for the work with the asbestos or ACM as identified in
the assessment, eg the prevention and control measures and the handlingand disposal of the waste (see paragraph 3.12); andthe type of equipment, including PPE and procedures, used for:– the protection and decontamination of those carrying out the work, including
details of the hygiene facilities, transit route and decontamination 		
arrangements, vacuum cleaners, air monitoring, protective clothing and
RPE, communication between the inside and outside of the enclosure;– the protection of other people at or near the work site, including the use of
barriers and signs, location of enclosures and airlocks, location of 		skips, NPUs, air monitoring, cleaning and clearance certification, emergency
procedures.

A POW should include a detailed site diagram
3.20 The ACOP suggests other things that could be included as good practice.
These are details of checks undertaken for other hazards, the name of thesupervisor and the name of the organisation that will undertake site clearance
certification, and details of other nearby ACMs which have not to be removed.
Listing nearby ACMs should prevent confusion between the work being done andACMs remaining in place.

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3.21 In all cases, work should not be undertaken until there is a copy of the POW
available on site. The plan should be made available to employees, and to any
others involved in the work, as necessary. Full licence holders should also make theplan available to the analyst who is carrying out the four-stage clearance process.
The plan should remain on site for the duration of the work to which it relates.

The POW should be made available to employees, others involved in
the work and the analyst who will carry out the four-stage clearance
What does this mean in practice?
3.22 The POW should contain the site and task-specific information. This is theinformation which relates to the site and job, the layout and design of the work areaand enclosure, and the specific controls which will be employed. The POW should
contain such information as the location of the DCU, the transit route and how amodular DCU is to be deployed and restricted to use by one or two people etc.
3.23 Generic information covering company procedures should not be included
in individual POWs. Instead this information should be contained in the latest versionof the company’s standard procedures, a copy of which should be held on every site.
These procedures only need to be expanded upon in the individual site-specific POW
when the site proposals differ from the generic information.The items that can becovered in standard procedures are listed in Box 3.1.
Box 3.1 Items that can be covered in standard procedures
■■
■■
■■
■■
■■
■■
■■
■■

Some control measures (eg construction and testing of enclosures, barriers,
warning notices etc).
Use of PPE including RPE (eg selection, use, face fits, system of coloured
coveralls etc).
Air monitoring (eg personal, background etc).
Site inspection (eg supervisory arrangements).
Checking and maintenance of equipment (eg testing and certification of
NPUs and RPE etc).
Decontamination (eg preliminary and full procedures, hygiene facilities etc).
Waste (eg bagging, transporting, storage).
Emergency arrangements (eg fire, enclosure breach, unplanned ACM
disturbance etc).

3.24 A copy of the current version of the company’s standard procedures,
bearing
the relevant reference number and date, should be sent to the HSE Head Office
ALPI for their retention and future reference. A copy, where requested, should
also be made available to other enforcing authority inspectors and any personnel
involved in the work. This applies to all licence holders.

Generic POWs are not acceptable, unless they are designed tocover a series of very similar asbestos removal jobs, such as at
a block of flats or a series of houses in one location where themethod is applicable to each property
3.25 Paragraphs 3.26-3.31 provide a practical interpretation of the ACOP
requirements in respect of the POW for the three different types of licence holder,
namely full, supervisory or ancillary licence holders (ALHs). The paragraphs
summarise the site-specific information that should be considered in a POW foreach of the different licence holders. (Remember however that the site-specificinformation should be expanded upon in the POW if it differs from the genericprocedures).
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What should be considered in POWs by full licence holders?
3.26 The site-specific details that should be covered by full licence holders are as
follows.
Details of contract
n The name and local address of the people to whom the licence holder iscontracted.
n The names, job titles, and telephone numbers of all relevant contacts,
including the site supervisor and the competent person preparing the POW.
n When the supervisor will be on site.
n The number of employees on the job at any time.
n When the work is going to take place, ie dates and times (days, nights,
weekend work, etc), the dates for set up, removal and clearance.
n The names of the principal contractor, the planning supervisor and client, if theConstruction (Design and Management) Regulations 199411 apply.
n The name(s) of any other asbestos licence holders involved.
n The name of the analyst or organisation that will carry out the four-stage
clearance process and issue the certificate of reoccupation. It should also
state who has contracted the analyst.
Scope of work and RA
n Brief details of any asbestos survey, the level (Type 1, 2 or 3) who did thisand when.
n A description of the work, its location and the removal method.
n The type and form of asbestos, the quantity, extent and condition.
n Brief details of any access and fire risks and precautions taken, and any otherrisks (eg working at heights, hazardous substances).
n Who has authority to consider departures from the POW and how will these
be noted and recorded on site, and reported to the enforcing authority?
Control measuresn The expected exposure using the controls specified.
n The steps taken to reduce exposure as low as reasonably practicable and tocontrol release into the environment.
n A site diagram - see Box 3.2.
n The volume of enclosure, size and numbers of NPUs and number of airchanges per hour.
n If NPUs conform to PAS 60-2 (see Box 7.1).
n The type of respirators actually used.
n The air monitoring arrangements for the duration of the work.
n The arrangements for smoke testing and witnessing.
n The arrangements for maintaining control measures on site and what checks
are to be in place.
Method of work for removaln Any additional precautions to reduce exposure.
n Detailed site information and a site-specific description of the working method
to be used with reasons.
n Details of the fibre-suppressant technique to be used.
n For a wet strip system: describe the injection technique, approximate timeallowed for penetration, what indicator will be used to check all the material isfully saturated. State whether equipment complies with PAS 60-1 standard(see Box 7.1).
n The tools and other equipment to be used.
n For AIB work, details of the practical measures to minimise dust release, andinformation on the way the ACM is fixed to the substrate.
n For other wetting systems, state the type to be used, eg airless spray, spray
unit.
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Other relevant site-specific information (but only where it differs from thestandard procedures)n DCUs (eg use of modular units, security issues).
n Entry and exit procedures to the areas of working.
n Welfare facilities.
n Waste disposal.
n Emergency procedures.
Box 3.2 Site diagram
The diagram supplied as part of the POW should show the following:■■ the enclosure(s) or work area(s);■■ adjacent rooms or areas to the enclosure or work area;■■ location of viewing panels;■■ location of NPUs;■■ location of the airlock;■■ location of the baglock;■■ location of the hygiene unit;■■ location of the skip;■■ transit route;■■ waste route;■■ size and dimensions of the enclosure or work area, adjoining rooms, transit

and waste routes.
What should be considered in POWs by supervisory licence holders?
3.27 The supervisory licence enables the holder (ie SLH) to have direct andimmediate influence and control over site activities to assist all dutyholders involvedin the work in achieving compliance with CAWR. For SLHs, the POW needs only
to spell out site-specific details in relation to the licence holder’s role supervising
the main removal contractor. The site-specific details that should be covered by the
SLH are as follows.
Details of contract
n The name and local address of the SLH’s client, ie people the SLH iscontracted to.
n The name of the licensed asbestos contractor(s).
n The names, job titles and telephone numbers of all relevant contacts, including
the site supervisor and the competent person preparing the SLH plan of work.
n When the SLH supervisor will be on site.
n When the work is going to take place, ie dates and times (nights, weekend
work, etc), the dates for set up, removal and clearance.
n The names of the principal contractor, planning supervisor and CDM client, if
CDM applies.
Scope of work and RA
n Brief details of any asbestos survey, survey type (ie Type 1, 2 or 3), author anddate.
n A brief description of the work to be undertaken by the licensed removal
contractor(s) and its location and the removal method.
n The type and form of asbestos, the quantity, extent and condition.
n Brief details of any access and fire risks and precautions taken.
n The terms of reference for the SLH’s involvement in the work (what exactly will
the SLH be doing?).
n Who will consider departures from the POW and how will these be noted andrecorded on site.

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Supervisory licence holder’s ‘own work’n The arrangements for communications with the various parties involved, ie the
SLH’s client, licensed removal contractor(s), analysts etc. Does the SLH’s client
and the licensed asbestos contractor understand the role?
n The arrangements to check the licensed contractor’s documentation (egtest certificates for equipment; medical certificates; method statements;
maintenance records; site log (including daily check of the enclosure and DCU);
training records (for asbestos work); face-fit test records for RPE; records of
RPE inspection; copy of the licence).
n The type of respirators used.
n The arrangements in place to stop or modify work practices (is the SLH certainthat they have the power to ensure that action is taken?).
n The arrangements for air monitoring (when, where, by whom, type, recording of
exposure levels).
n The arrangements for four-stage clearance procedure and the arrangements
to resolve any issues that arise, eg unsealed surfaces in the enclosure or a wet
enclosure.
n The arrangements for DCU clearance testing.
Other relevant site-specific informationn Use of the DCU.
n Entry and exit procedures.
n Welfare facilities.
n Emergency procedures.
What should be considered in POWs by ancillary licence holders?
3.28 The site-specific details that should be covered by the ALH are as follows.
Details of contract
n The name and local address of the people to whom the ALH is contracted.
n The name of the licensed asbestos contractor(s).
n The names, job titles, and telephone numbers of all relevant contacts, including
the site supervisor and the competent person preparing the POW.
n When the ALH supervisor will be on site.
n The number of employees on the job at any time.
n Details of when the ALH’s work is going to take place, ie dates and times(nights, weekend work, etc), the dates for scaffold erection, dismantling etc.
n The names of the principal contractor, planning supervisor and CDM client, if
CDM applies.
Scope of work and RA
n A description of the work and its location.
n The type and form of asbestos, the quantity, extent and condition.
n Brief details of any access and fire risks and the precautions taken.
n Who will consider departures from the POW and how these will be noted andrecorded on site.
Control measuresn What measures will be used to reduce exposure.
n The type of any respirators used.
Method of workn Detailed site information and a site-specific description of the working method
to be used with reasons.
n What tools and other equipment are to be used.

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Other relevant site-specific informationn Use of the DCU.
n Entry and exit procedures.
n Welfare facilities.
n Emergency procedures.
When and why do POWs have to be provided to enforcing authorities?
3.29 POWs should be provided to the enforcing authority as part of thenotification process at least 14 days before the work is due to start (seeparagraphs 3.32-3.35). The enforcing authority does not approve POWs. However
the notification period gives the enforcing authority the opportunity to assess the
proposals contained in the POW and to inspect the site either before or during
the work if they choose to. If a particular POW does not contain the minimum
information required by regulation 7 of CAWR, it is liable to be rejected. The licenceholder will be informed of the deficiencies and may have to resubmit their POW.
Where resubmission is required, a new 14-day notification period will apply.
When should POWs be reviewed?
3.30 As with RAs, POWs should be reviewed when there is reason to suspectthey are no longer valid, particularly if:
n
n
n
n
n
n

fibre control methods change (eg multipoint injection replaced with airlessspraying);
there is doubt about the efficiency of the control measures (eg dry patches
occurring during multipoint injection removal);
there is a significant change in the type of work, method of work, or extent of
the work (eg more and/or different types of ACM are discovered);
there is a change of site layout/access arrangements;
the results of air monitoring indicate the exposure levels to be higher thanpreviously assessed; orthe results of medical surveillance show that a review is necessary.

3.31 Any changes made later must be recorded in writing and be notified (inwriting) to the enforcing authority and employees.

Notifications and waivers
Notifications
3.32 As indicated in Box 2.1 and paragraph 3.29, licence holders are required
as a condition of their licence to notify the enforcing authority (either HSE or the
local authority) with details of the proposed work at least 14 days before it is due
to start. The notification consists of a completed ASB5 form (see Appendix 3.1) (orequivalent), a suitable and sufficient POW (or method statement) and equipment
specification, and a copy of the licence. Each licence holder involved in aparticular job (ie, full, supervisory or ancillary licence holder), must submit their own
notification.
3.33 All notifications received by HSE are subject to an administrative check forcompleteness, timeliness of submission etc. If any of the papers are missing (eg thesite diagram) or are inadequate, then the notification is incomplete and the 14-day
notification period will not start. Enforcing authorities do not agree or approve
notification, nor do they approve method statements/POWs or acknowledge receiptof them. However, licence holders are encouraged to submit their notifications to
HSE by e-mail and to set their system to receive an automatic acknowledgement ofreceipt.

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3.34 A proportion of notifications are selected for closer scrutiny. As outlined inparagraph 3.29, if HSE finds deficiencies, then the licence holder will be informed
and may have to resubmit their POW. The 14-day notification period will only start
once a modified plan is received. Any changes to the POW should be notified
in writing to the relevant enforcing authority office. Again, the notification period
will only start when the modified papers are received in the appropriate enforcing
authority office. Papers arriving outside normal office hours will be deemed to havebeen received the next working day.
3.35 Employers doing work on asbestos insulation, asbestos coating and AIB on
their own premises, with their own employees, are exempt from holding a licence,but they must notify under regulation 5 of ASLIC. This requires them to give therelevant enforcing authority 14 days written notice of their intention to carry out
work. The notification should include the address and telephone number where
the work is to be carried out, and a description of the work. A single notification ispermissible for work which is likely to be regularly repeated on the premises.
Waivers
3.36 There may be occasions when a genuine emergency arises, as a result of
which the enforcing authority may allow a shorter period before the work begins.
3.37 It is HSE’s policy that waiver requests will be granted only when there is agenuine emergency or equally pressing reason. Examples of such situations are:
n

n

n
n

cases where there is an imminent risk to health, the environment, or where
there is public alarm, and the risk cannot be avoided simply by leaving the area
and allowing it to remain undisturbed, and/or the area cannot be sealed;cases where asbestos is found during work and its presence would not havebeen reasonably foreseeable or reasonably practicable to detect (eg unless
an intrusive Type 3 survey was undertaken), and where the delay caused by
waiting for the 14-day notification period before dealing with the asbestos
would lead to significant financial loss;
cases where a breakdown in plant or equipment requires urgent remedialaction;cases where there is or is liable to be worry or hardship for domestic clients,
including old or infirm people.

3.38 In an emergency, a waiver may be granted based upon telephone
notification. However this must be followed by the paperwork listed in paragraph
3.40.
3.39 Waivers are unlikely to be granted to accommodate lack of foresightand planning by a client or contractor, unless an immediate risk of significant
exposure has been created and the area concerned cannot be sealed off toprevent that exposure.
3.40
n
n
n

All waiver requests must be sent with:

the ASB5;
a suitable and sufficient method statement and equipment specification,
including a site diagram (see Box 3.2);
written confirmation from the contractor’s client to support the request (ieevidence from the client that there is an emergency or equally pressing reason,see paragraph 3.44).

3.41 If disaster recovery work is proposed at short notice out of normal hours,
HSE will accept a request by fax or e-mail (local office arrangements for the latter
permitting) to waive the normal 14-day notification period for emergency weekend
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or bank holiday work provided:nnn

the request is made as soon as practicable after the company is asked toundertake the work;
the work with asbestos material is limited to that which is necessary to deal
with the immediate emergency to make a situation safe; andthe request includes the information normally expected for any waiver request,
as listed in paragraph 3.40.

3.42 HSE will review any requests for waivers received in such circumstances tocheck that they satisfy these criteria. If it transpires that companies making out-ofhour requests appear to be undertaking work which does not arise from a genuine
emergency, HSE may consider enforcement action, licence amendment or refusal
to accept further waiver requests from such companies.
3.43 The dates stated on the waiver request for a smoke test and for the startof work must be adhered to unless alterations are agreed with the appropriate
inspector.
3.44
n

n
n
n

n

Written confirmation from the contractor’s client should provide:

client and location details. This should include the name and address of theclient, the nature of the activity at the client’s address, the number of people
based there and the number affected by the asbestos-related problem;
a description of the location of the asbestos, its type and condition before theproblem arose;a description of the steps taken to identify and manage the asbestos in thesepremises (submitting the asbestos survey report if applicable);a description of the nature of the problem in detail, the extent of the damage
to asbestos and how and why it occurred, and whether the damage wasforeseeable;
a detailed description of the consequences if a waiver to the 14-day notification
is not granted.

Paperwork required on site
3.45 The list below outlines the paperwork that should be on site for the duration of
the contract. If original certificates are not available on site, the copies kept on siteshould be authenticated at a senior management level to provide confirmation of
their validity.
For the contract
n Current asbestos licence.
n POW (method statement), including details of any modifications that have been
made and notified to the enforcing authority.
n ASB5 notification and waiver (where granted).
n Other RAs (including assessments under the Control of Substances Hazardous
to Health Regulations 2002 (COSHH) (as amended)16 and assessments madeunder the Management of Health and Safety at Work Regulations 1999).10
n Employer’s liability compulsory insurance certificate.
n A copy of the company’s current standard procedures.
n Site log.

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For the equipmentn Test certificates for NPUs and any other plant in use (as appropriate).
n A clearance certificate for the DCU.
n Inspection reports for RPE, thorough examination and test plant etc.
n Daily records of checks on enclosure, DCU and air extraction.
n Smoke test certificate.
For your employeesn Medical certificates for all personnel working with asbestos.
n RPE face-fit records for all personnel working with asbestos. Where several
pieces of RPE are in use, face-fit records should be on site for all types.
n Training records for all personnel working with asbestos.
n Personal monitoring results (if performed).
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Appendix 3.1 ASB5 notification

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Appendix 3.2 Site diagram(a)

Airlocks
Enclosure wall
Plant room
CanteenGround floor
NPU
First floor

Skip

DCU

Recording of the site layout
as a diagram, (a) shows the
3-dimensional layout and (b) is an
example of how the site could berecorded as a clearance diagram.
Dark areas show work areas andlight areas show other areas which
need to be inspected.

Tent

(b)
Airlocks

Work areas
For inspection
Plant
room

Canteen
NPU
Main car park

Skip

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Chapter 4: Training for
employees, supervisors andothers working with ACMs

Summary
n
n
n
n
n
n

Employees of licensed asbestos companies should not be allowed to start
work without having received the appropriate level of training.
There should be a clear training strategy and policy.
Take care over either the development or choice of the appropriate training
courses, with particular reference to the use of a training needs analysis.
Training courses should be designed to meet the course criteria in
Appendix 4.3 and the course content in Appendices 4.1 and 4.2.
Training is not an end in itself and must be followed up by on-the-job
consolidation of the knowledge and skills acquired.
Senior management should ensure that the training policy continues to be
implemented and is still relevant.

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Contents
Introduction

56

Why is training required?

56

Training strategy model

56

Stage 1: Drawing up a training policy 57
Stage 2: Identifying training needs 57
Stage 3: Choosing an external training course or developing in-house training 57
Stage 4: Checking that appropriate training has been delivered 61
Stage 5: Record-keeping 61
Stage 6: Consolidation of skills and knowledge 62
Stage 7: Monitoring, auditing and policy review 62
Further information 62

Appendix 4.1: Asbestos training modules 1-23 (scaffolders 20-23 only):
Initial training 63
Appendix 4.2: Asbestos training modules 24-27: Practical training

70

Appendix 4.3: Course criteria for people carrying out or supervising asbestos
removal or ancillary work 71
Appendix 4.4: Carrying out a TNA

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Introduction
4.1
This chapter explains the nature of the training that should be given to thevarious types of personnel involved in licensed asbestos removal work, ie asbestos
removal organisations, SLHs and ALHs. The guidance contains an outline plan for
the training required for the different personnel. The training topics are presented
in the form of modules (see Appendices 4.1 and 4.2). The training modules havebeen prepared taking into account the European level report Final report on thedevelopment of practical guidelines for the training of asbestos removal workers.17
Appendix 4.3 contains the agreed design criteria that asbestos courses should
follow. The three appendices have been drawn up after consultation with theasbestos training providers known to HSE (a list is available at www.hse.gov.uk).
Why is training required?
4.2
Regulation 9 of CAWR requires employers to ensure that adequate information,
instruction and training are given to their employees who are liable to be exposed toasbestos or who supervise such employees. The aim of this regulation is to ensurethat employees are equipped with the relevant skills and knowledge to enable themto remove asbestos safely or to supervise such work, by minimising their exposure toasbestos.
4.3
Following this guidance will help employers to fulfil the training requirements
set out in paragraphs 42-60 of the ACOP, Work with asbestos insulation, asbestos
coating and asbestos insulating board. Control of Asbestos at Work Regulations
2002. Approved Code of Practice and guidance.12 This includes the need toprovide role-specific training for all employees working with asbestos.
4.4
Training on its own does not make people working with asbestos‘competent’. Training must be consolidated so that the person becomes confident,
skilful and knowledgeable in practice on the job (see paragraph 4.37).

Training strategy model
4.5
To assist in meeting training needs, all organisations involved in asbestos
work should have a training strategy. Paragraphs 4.6-4.41 provide the details of amodel for a training strategy (see Box 4.1).
Box 4.1 Training strategy modelStage1: Drawing up a training policy.
Stage 2: Identifying training needs.
Stage 3: Choosing an external training course or developing in-house training.
Stage 4: Checking that appropriate training has been delivered.
Stage 5: Record-keeping.
Stage 6: Consolidation of skills and knowledge.
Stage 7: Monitoring, auditing and policy review.

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Stage 1: Drawing up a training policy
4.6
The training policy should set out the following points.
n
n
n
n
n
n
n
n
n
n

Who is responsible for managing the training policy.
How training needs will be identified.
Whether the organisation has the competence and resources to deliver training
itself or requires the assistance of a training provider.
What to do if an employee fails a training course.
How to determine whether training objectives have been met.
How training will be recorded and kept up to date.
How follow-up, on-the-job training will be implemented to consolidate new skills
and knowledge.
How to identify training needs for refresher training.
How to monitor and review the policy.
How the competence of the employee will be determined.

Stage 2: Identifying training needs
4.7
What is a ‘training need’? A training need is a specific change in behaviour
that is required to improve performance in a particular job or to bring a new
recruit up to speed. The technique called ‘training needs analysis’ (TNA) involves
a description of the difference between the existing behaviour and a desired
behaviour. For example, an experienced asbestos removal operative fails tofollow the correct decontamination sequence or a new recruit does not know theright way to decontaminate. In these instances, the training need would be ‘tounderstand and apply the decontamination procedure in the right order’ and a
training programme should be chosen or drawn up that meets this need. A guideto carrying out TNA and an accompanying flow chart can be found in Appendix
4.4. TNA is especially relevant for refresher training to ensure that the course is
tailored to the audience and is not a repeat of the basic training course. Everyone
employed to work with (or work ancillary to) asbestos insulation, asbestos coating
or AIB must have their training needs assessed before they start work or before
attending a refresher course. TNA can be carried out on a group of people and notjust on an individual basis. Training needs should be identified by managers as partof ongoing site monitoring. It is an employer’s responsibility to ensure that a TNA iscarried out, either in-house or with help from external consultants.
Stage 3: Choosing an external training course or developing in-housetraining
4.8
Training can be delivered in-house provided that the expertise and resources
are available. Staff should have the necessary skills, knowledge and experience
to be trainers (see paragraph 4.29) and there should be suitable training facilities.
The alternative option is to use external training expertise. In both instances theguidance in paragraphs 4.9-4.29 can be used to find/develop suitable training forasbestos workers.
Course content
4.9
The content of the different types of training has been set out in a series ofmodules covering core topics for basic training, role-specific modules and refresher
training. These modules are based on the list of training topics set out in the ACOP,Work with asbestos insulation, asbestos coating and asbestos insulating board.
Control of Asbestos at Work Regulations 2002. Approved Code of Practice andguidance12 (see Appendices 4.1 and 4.2). When choosing an external course ordesigning an in-house course, these modules should be followed.

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4.10 Appendix 4.3 sets out training course design criteria such as duration, tutor
to delegate ratio etc, for basic, role-specific and refresher training. These criteria
have been agreed with the asbestos training providers listed on the HSE website.
Training providers should be questioned to ensure that the course meets thesecriteria. Companies providing in-house training should also follow these criteria.
Practical training
4.11 A review of training provided for operatives and supervisors carried out
by the Health and Safety Laboratory (Review of training provided to asbestos
removal workers),18 concluded that more emphasis was required on the deliveryof ‘practical’ training to ensure that employees could follow essential procedures
correctly. The term practical in this context means hands-on training where
delegates practice going through procedures, usually in a simulated environment.
For example:
n
n
n
n
n

carrying out decontamination procedures by showering etc using a powered,
live hygiene unit (uncontaminated);
trying out RPE to ensure a good face-fit and knowing how to carry out
maintenance checks;
the simulated use of controlled wet stripping techniques, such as multi-needle
injection systems;
construction of enclosures and airlocks;
maintenance of plant and equipment.

4.12 In general, where the training aims to impart knowledge, it will be mostly
theory-based. When the training is about providing skills, the emphasis should beon practical training. The latter can be supplemented through the use of exercisesand demonstrations including showing videos, taking part in case studies andvisual demonstrations.
4.13 It will be important for the employer to check that the training course
includes modules which have a practical element as described in Modules 24-27
in Appendix 4.2, and includes a means of gauging attainment levels. Both practicaland theoretical sections of the course should be carried out by the same training
provider.
Health and safety of delegates
4.14 Health and safety issues should be considered during practical training
sessions. The training provider should be asked what steps have been taken toassess the risks of running practical sessions, eg risks from slips, trips and falls orfrom electric shock.
New recruits
4.15 ‘New’ employees may have worked in the industry before, but it should
not be assumed that their experience is sufficient to dispense with further training.
For example, new recruits may be unaware of their employer’s safety policy, inparticular systems of work currently in force or the protective equipment used. They
may also have received inadequate training in the past and may not fully appreciate
the dangers of asbestos. Induction training covering in-house health and safety
procedures will therefore be necessary for all new employees even if they havealready received basic training in asbestos. This will include training in health risks,
emergency procedures, waste disposal and the company’s own induction before
being allowed to work even outside the enclosure.

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Existing employees
4.16 The continuing training needs of existing employees should be assessed
regularly. Information and training updates on, eg new working techniques
or changes to legislation should be given at the earliest opportunity. Do notnecessarily wait for the annual refresher training which, although it is a usefulvehicle for getting such information across, may be too far in the future. Evidence
of delegates’ successful completion of basic training should be provided to external
training providers before enrolling them on refresher training.
Types of training
4.17 Delegates with different roles should not participate in the same course.
Training will be based on the role of the employee. In addition, training will dependon the experience of the employee. It is divided into two categories:nninitial training;refresher training.

Initial training
4.18 Initial training is required for employees new to licensed asbestos work. Thereare certain key topics that must be covered by people involved in asbestos removal
work, including SLHs, managers and directors. The depth to which trainers go
will be dependent on the TNA and the role carried out by the individual(s). The
Initial Training Modules 1-23 are set out in Appendix 4.1. Modules 20-23 apply toscaffolders only.
4.19 There are particular areas of training that are specific to the role of theemployee. However, there are some job holders who will have to cover all topic
areas to gain an understanding of what the others do, so they can manage or
supervise them. Such job holders include managers, directors and SLHs. Rolespecific Modules are incorporated into Appendix 4.1 and include the following
roles:nnnnn

operatives;supervisors of asbestos removal work;
managers and directors of asbestos removal work;
scaffolders (and scaffolding management);
SLHs.

Refresher training
4.20 The aim of refresher training is to identify good and bad practice and toensure that the good practice is shared and that bad practices are stopped. TNA
will help to make the annual courses more relevant to delegates. Refresher training
should aim to achieve the following objectives:
n
n
n
n
n

fulfil identified training needs;
impart new information, eg changes in legislation and work practices (such asuse of new equipment or wetting techniques);
remind employees of the risks they face working with asbestos;
reinforce procedures such as the use of hygiene facilities, use and maintenanceof RPE and how to use controlled removal techniques;
share good practice and eliminate bad practice.

4.21 It is important to ensure that staff are booked on the appropriate course,
ie a refresher training course and not a repeat of the initial training modules. In theformer there will be greater emphasis on carrying out practical training throughthe use of demonstration techniques. If training needs are identified that require
practical training, the course time may need to increase to incorporate suchsessions.
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4.22 The term ‘supervisor’, ‘manager’ and ‘director’ relate to the person’s
responsibilities and the function of their role and not their job title. It is essentialthat people are sent on the course or series of modules that best reflect their role.
The subjects in the modules outlined in Appendices 4.1 and 4.2 will vary in depth
according to the role of the delegates. For example a supervisor will need to havegood fault-finding skills to check conditions on site, whereas a director will only
need an overview of what checks the supervisor should be carrying out.
4.23 Where only two or three operatives will be on site for the duration of thejob (without a floating supervisor), one person should be acting in a supervisory
capacity. The person should have been trained at a supervisory level and have thenecessary skills and authority to supervise the others.
4.24 Directors should know about the licensing requirements and the implicationsof not complying with the standards set out in the ACOPs and asbestos legislation.
Assessment
4.25 The content of training and pace of delivery should be influenced by an
employee’s previous knowledge and experience. A trainee’s performance should beassessed at regular intervals so that the course instructor can keep the employer
informed about his or her progress. A test, set by the course instructor, should
indicate that the trainee has successfully completed the training programme. It will
also be appropriate to assess performance in practical sessions, such as the fittingof RPE (see Module 25, Appendix 4.2).
4.26 A trainee whose final assessment is unsatisfactory, or who has notcompleted all the core modules, should not be permitted to work in areas where
exposure is liable to exceed the relevant control limit until additional training has
been given and he or she has achieved a satisfactory pass mark (see ‘Assessmentof attainment levels’ Appendix 4.3).
4.27 As an employer it is important to check that the training provider will assessdelegates, as it is no longer acceptable for delegates to receive a training certificate
for attendance only. Delegates should be informed of their pass mark and should
be given a copy of their training certificate.
Delivery techniques
4.28 HSL’s report concluded that it is very important to motivate delegates toparticipate in the training. It is particularly important to remember that the majorityof the delegates will not be used to being in an educational environment and are
more used to learning by doing. Ask the training provider which of the following
techniques they use to motivate delegates:nnnnvariation of delivery methods, eg videos, lecture style, exercise, practical;
making the training objectives relevant to delegates’ work and role;encouraging group discussion;
providing feedback on progress by the means of assessment.

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Competence of trainers
4.29 All training should be provided by instructors who are competent, ie they haveadequate personal practical experience in the asbestos sector, theoretical knowledgeof all relevant aspects of the work and the ability to deliver effective training courses.
There are no set training requirements for trainers. There are, however, National
Vocational Qualifications (NVQs) available in training. Trainers should be capable ofidentifying the most appropriate methods of presentation, how to design and evaluate
courses and how to carry out the assessment of delegate performance. Employers
should make enquiries about the trainer’s experience and relevant qualifications.
Stage 4: Checking that appropriate training has been delivered
4.30 Employers should have checks in place to ensure that the correct training
programmes have been delivered and that the right people have received the righttraining, ie that new asbestos workers have covered the initial modules and have
not received refresher training aimed at experienced employees.
4.31 At the end of a course the training provider should confirm whether
employees have passed the relevant modules. Employers should go on to checkthat any specified additional training objectives (ie outside the standard modules)
have been met. If some training objectives have not been met, employers should
review the initial training needs. It should be established with the training provider
whether the delegate should go on a different type of course and/or the reasons why
the objectives have not been covered in sufficient depth. Employers should ensurethat employees’ training objectives have been met during the training programmes
attended. The design and content of courses should be checked on a regular basis,eg annually, to ensure that they are still up to date and take any legislative changes
into account.
Stage 5: Record-keeping
4.32 Records need to be kept in order to demonstrate that the workforce
has been suitably trained and that their training has been kept up to date. Suchinformation will be required at asbestos licence interviews, carried out by HSE
inspectors, as part of the Asbestos Licence Assessment Guide procedure.
4.33 Employees should be given a copy of their training certificate/record.
Originals can be kept centrally and copies sent to individual sites. Such information
should be carried to site to be checked by visiting Enforcing Authority Inspectors
or to accompany the Construction Skills Certification Scheme (CSCS) card. This
card is an entry requirement for larger sites managed by members of the Main
Contractors’ Group (MCG) involved in the CSCS scheme.
4.34 It is the long-term aim to have an industry-wide, recognised identity card
for asbestos removal workers. Currently, the different training associations andindividual training providers create their own certificate or identity card. Employers
should ensure that any such certificate or identity card supplied by a training
provider or by a new employee has the following:
n
n
n
n
n
n

a unique numbering system;
the card holder’s National Insurance number;the person’s photograph;the date(s) of the training course(s) and renewal date;the type of course(s) and the modules passed;
the name, address and contact details of the training provider.

4.35

The materials used for the card or certificate should not be easy to forge.

4.36 In order to build up evidence of worker competence, employers can use
logbooks to demonstrate the type of work that the employee has been carrying
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employees trying to obtain the NVQs in Removal of Asbestos Containing Materials,
Level 2. Adequate record-keeping is essential for effective monitoring (seeparagraphs 4.38-4.40).
Stage 6: Consolidation of skills and knowledge
4.37 It is essential for recently trained employees, particularly those new toasbestos work, to consolidate their newly acquired skills and knowledge by putting
them to use on the job. Supervisors and managers will play an important role incoaching these members of staff by reinforcing good work practices and correcting
any bad ones. Where persistent problems occur, re-training may be required. It is
important to begin the consolidation process as soon as possible after training has
been provided, but certainly within three months. Some form of assessment will be
required to gauge how well the employee is performing. Logbooks can be used torecord examples of work done which demonstrate the application of specific skills.
Stage 7: Monitoring, auditing and policy review
Monitoring
4.38 To ensure the effective implementation and review of the policy, all aspectsof the training programme should be monitored. Supervisors will play an importantpart in the day-to-day monitoring, but formal monitoring should be the responsibilityof senior management. Directors or owners of the company should take an overall
interest in and responsibility for the training programme and should monitor its
effectiveness. The monitoring arrangements should be set out in the safety policy.
Auditing
4.39 Training courses should be audited in some way to establish that they meetthe course criteria set out in this guidance and that syllabi have been delivered
effectively.
Policy review
4.40 The training policy, like all health and safety policies, should be reviewed ona regular basis. As annual refresher training is required, it may be appropriate toreview whether the training policy is still relevant to business needs on an annual
basis. Further guidance on how to monitor and review policies can be found in the
HSE guidance booklet Successful health and safety management.19
Further information
4.41 For detailed guidance on syllabi, criteria and assessment, contact any of
the training providers on the HSE list of training providers (see www.hse.gov.uk) or
contact the ALU.

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APPENDIX 4.1: ASBESTOS TRAINING MODULES 1-23 (SCAFFOLDERS 20-23 ONLY): INITIALTRAINING
Module no

Title

Module 1

Types uses and risks of ACMs

1A

Operatives
Types of asbestos fibres – characteristics, uses, identification methods (introduction), natureand levels of risk for different groups of ACMs; history of import, manufacture and installation ofdifferent ACMs; types of products that may contain asbestos; likely locations; previous treatment
methods covering old asbestos applications; ACMs’ friability/conditions when they will releasefibres; recognition and need for control; emergency and remedial work

1B

Supervisors
As for operative, ACMs – know how the presence of asbestos can be confirmed (bulk sampling
and analysis)

1C

Managers/directors and SLHs
As for supervisors

Module 2

Health hazards of asbestos

2A

Operatives
How fibres cause disease; types of asbestos-related diseases and how related to exposure;
medicals under CAWR; need for dust/fibre suppression to control exposure; need for correct use/maintenance of RPE; health effects of smoking and risks of taking home asbestos-contaminatedequipment/clothing etc

2B

Supervisors
As operatives

2C

Managers/directors and SLHs
As operatives plus outline of legal responsibilities (CAWR); civil vs criminal law

Module 3

Legislation

3A

Operatives
Duties of the individual; key duties of the employer; overview of licensing framework; control of
exposure – as low as reasonably practicable; overview of CAWR; requirements of the ACOP andassociated guidance; overview of Waste Regulations 20,21 and Environmental Protection Act.22
Action levels and control limits

3B

Supervisors
As operatives, but with emphasis on responsibilities of supervisor

3C

Managers/directors and SLHs
As operatives, but with emphasis on management responsibilities; knowledge of which workrequires a licence, the types of insurance cover required and sourcing of information on ACMs

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Module 4

Site set up, maintenance and dismantling

4A

Operatives
Set up:Need for pre-clean; vacuum cleaners; site layout, including citing of hygiene unit as close to
enclosure as possible; optimal positioning of air/baglocks and NPUs; explanation of how NPUs
work and the significance of the voltmeter and pressure gauges and what changes in thegauge readings mean; when pre-filters should be changed; strategy for calculating air changes;
connection and testing of hygiene unit; construction of enclosures, air/baglocks including possible
weather protection; positioning of clear viewing panels; positioning and wording for warning
notices and barriers; how to delineate work areas and transit routes; smoke testing and need forwitnessing
Maintenance:
Daily inspections of enclosure (start, middle and end of shift) and immediate rectification of
defects; strategy for NPUs to be kept running after stripping finishes for the day
Dismantling:
Once clearance achieved, spray enclosure with sealant, bag and seal vacuum cleaners, bag otherequipment, dismantle polythene and dispose of as asbestos waste; final inspection of area once
enclosure and all associated equipment have been removed

4B

Supervisors
Recognise which ACMs are not being removed as agreed with client. As ‘Operatives’ and checkcertificates for hygiene unit NPU, gas test, clearance in shower and dirty end from previous job,
NPUs and vacuum cleaners; how to check for negative pressure in the enclosure; ensure thatviewing panels (or other viewing means eg CCTV or webcams) are provided

4C

Managers/directors and SLHs
As supervisors

Module 5Controlled stripping techniques

5A

Operatives
Chapter 7 of this guide in detail, including principles of fibre suppression and control of exposure;equipment – use of, maintenance and cleaning; wet injection and spraying techniques; wrap-andcut; glovebags; direct vacuuming; LEV (shadow vacuuming); vacuum transfer; air management;
preparation time and testing of controls before removal; wetting agent selection, preparation
and use; COSHH requirements; anticipated and desired fibre levels and comparison with RPE
maximum exposure levels; personal assessment monitoring (principles); access to personalassessment information

5B

Supervisors
As for operatives plus equipment inspections and records, fault-finding and solutions.
Monitoring for effectiveness of fibre control techniques and recording information

5C

Managers/directors and SLHs
As for operatives and supervisors, plus equipment and wetting agent selection; maintenance andtraining requirements

Module 6

Respiratory protective equipment

6A

Operatives
The circumstances when RPE must be worn which may include: inspection of work area, building
and dismantling enclosures, working in enclosure, taking bags to skip; how to inspect, test andwear respirator; need for quantitative face-fit test, a good face seal and the need to be clean
shaven; correct storage, battery charging and keeping clean; strategy for changing pre-filters andmain filters

6B

Supervisors
As for operatives

6C

Managers/directors and SLHs
As for operatives
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Module 7

Personal protective equipment and clothing

7A

Operatives
The use of the appropriate PPE including: overalls, headgear, footwear and gloves; employer
requirements to provide appropriate PPE and employees’ obligations to use it; care, wearing,cleaning, decontamination and/or disposal of PPE; not taking contaminated PPE home; transit
overalls; when and where PPE should be worn; ensure correct use and maintenance of PPE

7B

Supervisors
As for operatives plus PPE use during transit procedures; contaminated clothing and waste;
keeping of relevant records

7C

Managers/directors and SLHs
As for supervisors, plus knowledge of practical difficulties of wearing PPE, such as heat/cold andlaundry requirements

Module 8

Transit procedures and decontamination

8A

Operatives
Personal decontamination procedures for directly connected and remote (transit) DCUs andairlocks including: PPE changing and disposal, showering, colour coding of coveralls, RPE
decontamination, cleaning, charging and storage; use of towels; changing and disposal of preand main RPE filters; decontamination procedures where no enclosure or DCU is required (opensites); common problems with decontamination; cleaning of airlocks and DCUs; emergency
decontamination in case of evacuation or accident; what should be in the DCU, ie mirror, soap/
shower gel

8B

Supervisors
As for operatives, plus common problems and fault-finding with decontamination; air monitoring
results in DCUs; inspection and record-keeping; the importance of ensuring that procedures arefollowed; making time available to allow adequate showering; DCU checks (see Box 8.1)

8CManagers, directors and SLHs
As supervisors, plus interpretation of inspections and audit results; the importance of ensuringthat adequate equipment, materials and resources are made available to put the procedures inplace

Module 9

Cleaning and clearance air testing

9A

Operatives
Cleaning and clearance requirements, including the need for the four-stage clearance process
and associated certificate of reoccupation; visual cleanliness and air testing requirements;
methods of cleaning for enclosures, hygiene facilities and equipment; re-cleaning in event of
air test failure; cleaning after enclosure dismantling; cleaning in the event of an emergency or
enclosure/equipment damage

9B

Supervisors
As for operatives; the requirements of analysts before clearance inspection and sampling

9C

Managers/directors and SLHs
As for operatives and supervisors

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Module 10

Plant and equipment (using demonstration of equipment)

10A

Operatives
Equipment components; equipment use and maintenance including: NPUs, Type H vacuums andinjection equipment (RPE covered separately)

10B

Supervisors
Equipment components; equipment use and maintenance including: NPUs and monitors, TypeH vacuums and injection equipment; citing and daily maintenance of the hygiene unit; recordkeeping (RPE covered separately)

10C

Managers/directors and SLHs
Outline of components, use and maintenance of NPUs, Type H vacuums; use and maintenanceof injection equipment; citing and daily maintenance of hygiene unit; record-keeping (RPE covered
separately): need for new injection equipment to meet PAS 60 standard.

Module 11

Waste management and disposal

11A

Operatives
Bagging, sealing and cleaning; transportation through baglock and airlock; storage of asbestos
waste; correct loading of skip/van

11B

Supervisors
Outline of Waste Regulations; use of consignment notes; registration of carriers; role andpowers of environment agencies; transportation of dangerous goods; bagging, sealing andcleaning; transportation through baglock and airlock; storage of asbestos waste; correct loadingof skip/van

11C

Managers/directors and SLHs
As supervisors

Module 12

Emergency procedures

12A

Operatives
What to do in the event of major and minor injuries or illnesses occurring inside ‘live’ enclosures;
what to do in the event of fire, or some other hazardous release such as toxic gas or radioactive
dust occurring inside or outside enclosure; what to do a if leak of asbestos is found outside theenclosure; what to do if power on power-assisted respirator fails while inside ‘live’ enclosure; what
to do if the NPUs stop working; what to do if there is complete loss of electrical power; what to
do if loss of water supply to hygiene unit

12B

Supervisors
As operative, but confirming the responsibility of the supervisor to ensure that suitable emergency
procedures are in place to cope with the failure of any control measures or the injury or ill health ofa worker inside contaminated areas

12C

Managers/directors and SLHs
As operative and to confirm they are all in place and appropriate to specific site andcircumstances; assessing the competence of operatives and supervisors, importance of auditing
and monitoring work activities; notification of asbestos work

Module 13

Non-asbestos hazards

13A

Operatives
Site safety procedures; permit-to-work systems; entry and exit in case of fire; location of possible
site hazards; emergency procedures in case of fire, electric shock, burns, hazardous substances,solvents etc; care of injured casualty; manual handling, noise, vibration and falling object
protection, slips, trips and falls, eg working from scaffolding

13B

Supervisors
As operative, plus electrical checks for DCU (see Box 8.1)

13C

Managers/directors and SLHs
As supervisors, except electrical checks
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Module 14

Fault-finding

14A

Operatives
How to spot problems with wetting of ACMs, RPE, airlocks, enclosures and hygiene unit

14B

Supervisors
Work practices – how to spot problems with wetting of ACMs, RPE, airlocks, enclosures andhygiene unit; method statements; RAs; signs; record-keeping and fault reporting procedures

14 C

Managers/directors and SLHs
As ‘Supervisors’
Note: Managers/directors need an overview of fault-finding while SLHs need a far more detailed
session at the level of a supervisor

Module 15

Roles and responsibilities

15A

Operatives
To adhere to the principles of their training; to work to the RA and POW; when work should be
halted because it does not match the POW; to work safely and not to put others at risk from theiracts or omissions; to wear PPE and RPE correctly and to report any defects; to understand why
they should not take short cuts

15B

Supervisors
To ensure everyone complies with regulations, ACOPs, guidance and follows the RA and POW.
If the work method has to change - work is stopped and reassessed. The RA and POW are
amended and personnel informed of the changes in writing; to ensure all personnel are
instructed, face-fitted and have received a medical; all equipment is inspected and tested; alldaily inspections are carried out; all documentation is available and up to date; the importance ofbeing on site for key stages of the work and their crucial role in directing the work and monitoringstandards of work

15C

Managers/directors and SLHs
As above and to ensure that all activities and training meet the legal requirements

Module 16

Site inspections and record-keeping

16A

Operatives
Purpose of site inspections, site auditing and record keeping; role of inspector/auditor;
responsibilities of operatives; reporting faults and other problems

16B

Supervisors
As operative, plus criteria, for site inspections; actions in event of faults; record-keeping; scopeand nature of records, use of typical record and reporting systems

16C

Managers/directors and SLHs
As operative and supervisor, plus retention of data, including exposure records and healthsurveillance; methods and criteria; interpreting and monitoring records; fault-finding and solutions;data handling and the need for site audits

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Module 17

Management systems and monitoring

17A

Operatives
Maintenance and monitoring of control measures; controlling exposure to asbestos; ensuring that
equipment functions correctly; pre-start setting-up; barriers and signs; construction and testingof enclosures and airlocks; site monitoring; use/testing of negative pressure equipment andventilation and air management systems; correct maintenance of all site equipment - following
manufacturers’ operating instructions, including the correct maintenance and monitoring of
the following control measures: enclosures, external services, NPUs, wet strip units, mobile
generators, water supply, heating appliances, PPE, RPE, any dust suppression equipment, tools
and DCUs

17B

Supervisors
As for operatives, plus site supervision and record-keeping of work in progress; method
statements; POWs; monitoring and auditing work in progress

17C

Managers/directors and SLHs
As supervisors

Module 18

RAs and POWs

18A

Operatives
Introduction to RAs (know what they are for) – understanding the main points, right to see
significant findings; requirements to follow RAs and risks/penalties if not followed; the meaning of
the control limits and action levels

18B

Supervisors
As operative, plus carrying out RAs and developing a POW (instruction and exercise); changes
and amendments to RA/POW; seeking advice and informing of changes; notification to HSE
when change is significant and what is a significant change

18C

Managers/directors and SLHs
As operative and supervisor, plus notification to enforcing authority, review of RA/POWs, recordkeeping and storage of RA/POW

Module 19

Information, instruction and training

19A

Supervisors
How to implement and monitor on-job training (consolidation); how to assess the competenceof employees; the types of training available and how to choose the right course; TNA inpractice; recognising the need for additional training when new equipment or work methods are
introduced

19B

Managers/directors and SLHs
As for supervisors

Module 20

Scaffolders: Health risks and avoidance of exposure20

All levels
How to avoid exposure when working near asbestos; types of asbestos fibres - characteristics,
uses, identification methods (introduction); nature and levels of risk for different groups of ACMs;
types of products that may contain asbestos; likely locations; how fibres cause disease; types ofasbestos-related diseases and how they are related to exposure

Module 21

Scaffolders: Use of RPE, PPE and emergency decontamination procedures

21

All levels
How to recognise that exposure has occurred; how to deal with minor and gross contamination;
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Module 22

Scaffolders: Roles and responsibilities
All levels
Legal responsibilities of individuals, employer and management; the role of the asbestos removal
company and SLH; the information that should be shared between all parties

Module 23

Scaffolders: Management systems
Scaffold supervisors/managers/directors
RA and POW; introduction to what enclosures are for and how they are built; monitoring of site
conditions; site set-up; emergency procedures

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APPENDIX 4.2: ASBESTOS TRAINING MODULES 24-27: PRACTICAL TRAINING
Module no

Title

Module 24

Decontamination and transit procedures
The design, connection and citing of a DCU; explanation of preliminary and full decontamination
procedures and use of RPE and PPE; practising use of decontamination and transit procedures
in ahygiene unit that is plumbed in and fully operational and mock airlock/enclosure

Module 25

Use and maintenance of RPE
How to ensure the RPE is suitable for the user; how to fit RPE on site; how to check faulty RPE
andwhat to do if a fault is found; the components of each type of RPE; certification anddocumentation;
suitable storage; requirements of daily and monthly inspections

Module 26

Construction of enclosures and airlocks
Construction of an enclosure on a pre-erected 50 mm x 50 mm timber framework using 1000
gauge polythene sheeting, adhesive tape and staples; construction of a three-stage airlock
system on a pre-erected 50 mm x 50 mm timber framework using 1000 gauge polythene
sheeting and adhesive tape; construction of a three-stage airlock system using metal and/or
plastic framework; construction of a proprietary airlock system, eg a ‘transtent’; the use andlocation of viewing panels; the use and location of warning signs; smoke testing to determine
integrity; the construction and location of baglocks

Module 27

Use of controlled stripping techniques
The connection and use of an injection kit to wet pipe insulation, including the demonstration anduse of an effective needle system eg PAS 60 equipment – they should be able to determine thatneedles are the only effective way to wet insulation as a result of this session and the importanceof adjustable liquid flow rates; shadow or trace vacuuming – practice the removal of a tile or ductpanel using this techniqueAsbestos: The licensed contractor’s guide

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APPENDIX 4.3: COURSE CRITERIA FOR PEOPLE CARRYING OUT
OR SUPERVISING ASBESTOS REMOVAL OR ANCILLARY WORK
A4.3.1 The following criteria were drawn up after consultation with theasbestos training providers known to HSE (see www.hse.gov.uk). Courses
should meet these criteria. During a licence application or renewal interview
an ALPI will question any applicant’s training that does not meet thesecriteria.

Course content
A4.3.2 Modules for initial training can be found in Appendices 4.1 and 4.2. In using
these modules you are likely to achieve compliance with the training requirementsof Work with asbestos insulation, asbestos coating and asbestos insulating board.
Control of Asbestos at Work Regulations 2002. Approved Code of Practice andguidance.12 Courses should be role-specific, ie operatives and supervisors should
not be mixed together to avoid the more experienced personnel becoming boredand new operatives being afraid to ask questions.
A4.3.3 There is no reason why additional modules cannot be added to courses,
but those listed in Appendices 4.1 and 4.2 are the minimum required for each role.
The numbers of the modules that have been passed should be clearly stated on
the training certificate or card.

Duration of courses
A4.3.4 A day’s training means at least six hours, not including breaks.
Duration:
n
n
n
n
n
n
n

n

New operatives’ course: three days’ minimum (includes one day of practicalsessions).
New supervisors’ course: three days’ minimum (includes one day of practicalsessions).
Managers’ and directors’ course: two days’ minimum.
Scaffolders’ course: 0.5 day minimum.
Scaffolding supervisors’ course: 0.5 day minimum (additional to the 0.5 day
scaffolders’ training).
Managers and directors of scaffolding companies - one day minimum.
Supervisory licence holders’ course: 2-4 days (includes one day of practicalsessions). People may be exempt from certain modules if they hold relevant
BOHS qualifications. A TNA should identify the outstanding modules thatshould be covered in addition to these qualifications.
Refresher training for all roles: one day minimum (except for scaffolders andscaffold supervisors: 0.5 day).

Tutor to delegate ratios
A4.3.5 The HSL report recognised that there was a need for a high tutor todelegate ratio for practical hands-on training, such as use of decontamination
procedures. As a result, the following maximum ratios have been agreed for initialcourses:nnTheory-based sessions for all courses: 1 tutor to 12 delegates.
Practical sessions: 1 tutor to 6 delegates.

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As refresher training is mainly classroom-based, the ratio of tutor to delegates canbe raised up to 15.

Assessment of attainment levels
A4.3.6 It is important to know what knowledge and skills the delegate has before
starting the course, so there can be some measurement of improvement over theperiod of the course. You should provide the results of any TNA to the training
provider to assist them in adapting the course to make it as relevant as possible
to the delegates. There are various ways of assessing what the delegates havelearnt. Verbal feedback can be provided to the delegates as the course progresses,
especially during practical sessions. In addition, it is expected that a test will be
provided at the end of the course. It is expected that the delegates should achieve
80% or more in the test to obtain a pass mark. Oral tests should be offered topeople with learning difficulties. Special needs should be identified before the startof the course to adapt the training programme if necessary.
A4.3.7 Any delegate who fails the test should have some means of appealing
against the result and be allowed to retrain and/or resit the test within anagreed period of time. In the meantime, such a person should not be allowed
to work on site in areas where it is foreseeable that the relevant control limit
will be exceeded. It is no longer acceptable to have an ‘attendance-only’
certificate.

Practical sessions
A4.3.8 There will be more of a practical bias on courses for new operatives, newsupervisors, scaffolders and SLHs because there are certain practical skills thatneed to be acquired. Modules 24-27 listed in Appendix 4.2 are of a practicalnature. The term ‘practical’ in this context means that delegates are shown how
to do something and are then required to practise what they have been shownto acquire a new skill, eg fitting RPE. Such a practical session can only provide asimulation of site conditions. Consolidation of skills on site is essential.
A4.3.9 The core subjects that must be provided in the form of a practical module(in accordance with the ACOP)12 are:
n
n
n
n
n

the use of decontamination facilities;
the use and fitting of RPE;
the use of controlled stripping techniques (wet fibre suppression techniques
and other controlled stripping methods, such as shadow vacuuming);
construction of enclosures and airlocks;
waste removal procedures (by demonstration).

A4.3.10 Practical training should not be carried out in live working areas that
may be contaminated with asbestos.

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APPENDIX 4.4: CARRYING OUT A TNA
A4.4.1 The most important step in choosing training is determining what isneeded and ensuring that it is conducted as early as possible. Often, employers
opt for too little, too late when training their employees – this leaves employeeswith incomplete or inappropriate skills. Conducting a TNA will allow employers todetermine how many of their employees need to be trained, and what they need to
be trained in.
A4.4.2 A full scale TNA is a long-term project and will require the assistance of anexperienced training consultant who will use a combination of research techniquessuch as observation, questionnaires, interviews and focus groups. These techniques
enable the investigation of both the individual needs of the employees and theorganisational needs of the company. However, the following four steps provide helpful
information that will allow you, as employers of asbestos removers, to determine thetraining needs of your employees. This is particularly useful since TNAs are required for
all workers who are employed to work with asbestos insulation, asbestos coating or
AIB.

Step 1 Perform a gap analysis
A4.4.3 This process will assess current skills and desired skills to establish theextent of the skills gap, if any.
n
n
n
n

n

Identify the staff to be trained. What duties do the staff perform? Which ofthese involve hazards and which require training?
What is the experience, education and technical level of the trainees identified?
Have these trainees received training before? Does this previous training meettheir skills?
Is there legislation which affects the training to be given? (All asbestos
operatives and ancillary staff who work with asbestos insulation, asbestos
coating or AIB must have their training needs assessed before starting work).
What will the training accomplish?

Step 2 Identify causes of problems and/or opportunities
A4.4.4 It is unlikely that all the training needs that emerge from the first step can beaddressed immediately. So, the needs will have to be prioritised. Prioritisation canbe assisted by asking the following questions:nnnnDoes the need apply to all your employees or just those who work in particularareas?
Does the need apply to one or several individuals?
Does this type of training involve some form of knowledge or skill that may bedifficult for your employees to learn?
Is there legislation requiring the need to be met? If so, the training will need to
be provided regardless of the number of people it applies to, or the knowledge/
skill level of the training.

Step 3 Evaluate current training
A4.4.5 Once training needs and priorities have been established, a training plan will
have to be prepared. The current training arrangements should be assessed.

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A4.4.6 If there is a formal training department this will have to be evaluated tosee if the needs identified by Step 1 are being met. Even if there is not a formal
training department, there are likely to be some employee training materials suchas manuals and guidance. These materials can be integrated into any new training
solution. Review the procedures you already have in place, and be prepared toadapt them to your new training needs.

Step 4 Provide training and conduct an evaluation
A4.4.7 Once the needs have been prioritised and the training provided, the TNA
needs to be evaluated by conducting the four steps again. So, the TNA process isa cycle, which needs to be continually addressed, as demonstrated in Figure 4.1.
A4.4.8 The above steps only provide a guide to conducting a TNA. A full-scale
TNA is likely to require assistance from a qualified trainer and will be morethorough.

Figure 4.1 TNA flow chart
Step 1:
Perform a gap analysis

Step 2:
Identify causes of problems and/or opportunities

Step 3:
Evaluate current training

Step 4:
Provide training and conduct an evaluation

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Chapter 5: PPE for work with
ACMs

Summarynn

RPE:– RPE must be matched to the work, wearer and level of exposure;– wearers should be face-fit tested to ensure they have the correct device;– RPE should be kept clean, maintained and periodically tested.
Coveralls:– should be worn whenever there is a possibility of contamination withasbestos fibres;– can be non-disposable or disposable;– disposable should be Type 5 category 3.

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Contents
Introduction

77

RPE 77

Why should RPE be provided? 77
When should RPE be provided? 77
Control measures to apply before resorting to RPE 77
Specific requirements for RPE use 77
RPE and CE-marking 78
How to select suitable RPE for employees 78
Expected exposure concentrations 79
Protection factors 79

Face mask fit testing

Qualitative fit test 80
Quantitative fit test 80

79

Care, maintenance and testing of RPE

83

Looking after RPE 83
Air quantity and quality 84
RPE training for employees, including supervisors 84
Supervision 84
Some common misuses of RPE when working with asbestos

Coveralls

84

86

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Introduction
5.1
This chapter explains PPE, in particular RPE, its provision, use andmaintenance.

RPE
Why should RPE be provided?
5.2
Asbestos workers are potentially most at risk of developing asbestos-relateddiseases. Removal processes by their nature disturb and release asbestos fibres.
If the release is uncontrolled or poorly controlled, airborne fibre concentrations
can be extremely high (eg >100 f/ml). Even where effective controls have been
implemented, airborne fibre levels can still be in excess of the control limit. That
is why it is important that everyone who works with asbestos should take thestrictest precautions to reduce exposure to asbestos fibres as low as is reasonably
practicable. RPE plays a crucial part in the control regime. Its main purpose is to
reduce worker exposure (ie the number of fibres inhaled) when fibre levels in the
air around the worker are still significant and cannot be reduced further by othermeans.
When should RPE be provided?
5.3
CAWR requires employers to do all that is reasonably practicable toprevent exposure to asbestos fibres, or where prevention is not possible, toreduce exposure to the lowest possible level. RPE must be provided if, despite
the precautions taken, exposure to asbestos fibres is liable to exceed the control
limits laid down in the Regulations. The RPE must reduce the exposure as low as isreasonably practicable.

You should not use RPE as your only control measure as RPE canonly reduce exposure, not stop it
You must reduce asbestos fibre concentrations in air to a minimum
before using RPE
Control measures to apply before resorting to RPE
5.4
Exposure to asbestos should be prevented or reduced to as low as
is reasonably practicable by engineering controls before RPE is employed.
Engineering controls include: enclosure and extraction of the work area; wetremoval methods; wrap-and-cut and glovebag techniques; and shadow
vacuuming. These methods are described in detail in Chapter 7.

Uncontrolled dry removal processes are unacceptable
Specific requirements for RPE use
5.5
The law states that RPE used at work must:n be adequate and provide the wearer with effective protection;n be suitable for the intended use;n be ‘CE’-marked;
n be selected, used and maintained by properly trained people;
n be correctly maintained, examined and tested;n be correctly stored; andn have records kept of selection, maintenance and testing.

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Adequate

RPE is considered adequate if it can provide the level of protection required toreduce the exposure to comply with the law.

Suitable

RPE is considered suitable if it is adequate and is matched to the wearer, thetask and the working environment, such that the wearer can work with minimum
impediment and without additional risks due to the protective equipment.
RPE and CE-marking
5.6
The RPE provided for work with asbestos must be marked with a CE
symbol. The CE-marking means that the RPE meets minimum legal requirements
for its design and manufacture by conforming to a European Standard. The
CE-marking does not indicate that it is automatically suitable for a particular type ofuse.
How to select suitable RPE for employees
5.7
RPE needs to be selected very carefully and in consultation with employees.
Employers should also discuss it with the safety representative if there is one.
5.8
The equipment will need to be matched to the type of work to be done,
including the working environment, the wearer, other PPE in use and the exposure
concentrations (expected or measured). This means it will need to:
n

n
n
n
n
n
n

provide adequate protection (ie reduces the wearer’s exposure to asbestos
fibres as low as is reasonably practicable, and anyway to below the control
limits) during the job in hand and in the specified working environment (egconfined area or at height);
if fan-assisted, provide clean air at a flow rate and duration that conforms to
the manufacturer’s minimum specifications;if air-fed, provide clean air at a flow rate that at least conforms to the minimum
recommended by the manufacturer;
properly fit the wearer;
be reasonably comfortable to wear;
be properly maintained; andnot introduce additional hazards that may put the wearer’s health and safety at
risk.

When choosing RPE, employers will need to consider:
n
n
n

n
n
n
n

the expected concentrations of asbestos fibres in the air;
the protection factor values of different types of RPE (see Tables 5.1 and 5.2);
the potential for oxygen deficiency and/or the presence of other hazardous
substances (eg solvent vapours, carbon dioxide and carbon monoxide) within
the work environment. Employers should be aware that particulate filters used
for protection against asbestos fibres will not protect against oxygen deficiency,
gases or vapours. Work in oxygen-deficient atmospheres must comply with therequirements of the Confined Spaces Regulations 1997;15 carbon monoxide
can be produced from petrol or diesel-powered heaters and equipment;
the kind of work involved, eg more strenuous jobs may need a greater air
supply;the temperatures at which people will be working;the facial characteristics of the wearers (eg beards, sideburns, glasses etc);
the medical fitness of the people needing to wear the equipment; employees
need to be physically and mentally fit to work wearing RPE (and PPE),

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n
n
n
n
n
n

particularly inside an enclosure, as the CAWR medical examination is not afitness-for-work examination;
the length of time the person will have to wear the equipment;
how comfortable it is and whether people will wear it correctly for the required
length of time;
whether the job involves extensive movements, restrictions and/or obstructions
which need to be overcome;the need to communicate verbally during work;
the effects of other PPE and other accessories on RPE (eg unmatched goggles
may affect the face seal provided by the face mask); andjewellery or other adornments (eg piercing) worn by the wearer, which may
interfere with the fit of the face mask.

5.9
More details on these aspects can be found in the HSE guidance
Respiratory protective equipment at work: A practical guide.23
Expected exposure concentrations
5.10 The level of expected exposure should be established in the RA. The resultsfrom previous air monitoring can be used to assist the assessment. Some data on
the likely fibre concentrations for a range of asbestos jobs is given in Tables 1.1 and1.2. The data can be used as a guide, but it does not constitute an RA.
Protection factors
5.11 The expected exposure level is used to determine the minimum protection
factor required by the RPE. This parameter should be considered first in the selection
process.
5.12 Tables 5.1 and 5.2 list various types of RPE and the respective protection
factors (PFs). RPE with the highest PF should be considered initially. Then consider
whether this RPE is suited to the nature of the job, work-related factors, wearer’s
facial characteristics, medical fitness and comfort. Using this process, select themost suitable type of RPE for the job. The process is demonstrated through aworked example in Table 5.3. The chosen RPE must also be adequate for any
unexpected short-term high exposures. The reasons for selecting a particular typeof RPE should be recorded in the RA.
5.13 In practice, asbestos workers are likely to wear only a limited range of RPE.
A disposable type is likely to be used for various tasks including site pre-clean, site
set-up, inspection (four-stage clearance or initial), enclosure dismantling, waste
handling outside the enclosure, DCU cleaning, and scaffolding erection; and apower-assisted full-face respirator will be worn when entry into a live enclosure
occurs. In these situations FFP3 disposable masks and power-assisted full-faceequipment fitted with a P3 filter should be used respectively. However some people
may prefer to use half-masks rather than disposable equipment, and powered
hoods or blouses or air-fed equipment may be used in some circumstances inplace of power-assisted full-face masks (see paragraph 5.20).

Face mask fit testing
5.14 The performance of tight-fitting face masks depends on achieving a good
contact between the wearer’s skin and the face seal of the mask. As people’s faces
have a range of shapes and sizes it is unlikely that one particular type, or size offace mask, will fit everyone. Inadequate fit will significantly reduce the protection
provided to the wearer. To make sure that the selected face mask can provide
adequate protection for the wearer, a fit test should be carried out. The test should
be carried out as part of the initial selection of the RPE. There are two types of fit
tests: qualitative and quantitative fit tests (Note: fit tests should not be confused
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with the ‘fit check’, a procedure specified by the manufacturer which is used toverify that a good seal has been obtained each time the respirator is used (seeparagraph 5.18)).
Qualitative fit test
5.15 Qualitative fit testing is a simple pass/fail test based on the wearer’s
subjective assessment of the leakage, via the face seal region, of a test agent.
These tests are relatively simple to perform and are suitable for half-masks andfiltering facepiece (disposable) respirators. A qualitative fit test is not suitable for fullface RPE.
Examples of qualitative fit test methods:nnmethod based on bitter or sweet-tasting aerosol;
method based on odour compounds.

Quantitative fit test
5.16 Quantitative fit testing provides a numerical measure of the fit and generates
a ‘fit-factor number’. These tests give an objective measure of face fit. They require
specialised equipment and are more sophisticated than qualitative methods. Thesemethods should be used for full-face RPE and can be used for half-masks anddisposable respirators.
Examples of quantitative fit test methods:nnlaboratory test chamber;particle counting device.

5.17 Further details on RPE fit testing can be found in the document Fit testingof respiratory protective equipment facepieces.24 This can be downloaded from the
HSE website.

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Table 5.1 Respirator selection chart for protection against asbestos in air

PF

Filteringhalf-mask
BS EN 149

Valvedfilteringhalf-mask
BS EN 405

Filteringhalf-masks
without
inhalation
valves BS
EN 1827

Half-mask
BS EN 140
and filter
BS EN 143

40
20

FF P3

FF P3

FM P3

Full-facemask BSEN 136 andfilter BS EN
143

Poweredhoods andfilter
BS EN 146
BS EN 12941

Powerassisted
masks andfilter
BS EN 147
BS EN 12942

Mask + P3

TH3 hoods,
blouses + P3

TM3 full-facemask + P3

TH2
All types offace pieces+ P3

TM2 All types
of face pieces+ P3

Demandflow
compressed
airline BA
mask BS EN
139

Selfcontained
BA (SCBA)BS EN 137

Positivedemand fullface mask

Positivedemand fullface mask

Negativedemand fullface mask

Negativedemand fullface mask

Mask + P3

Table 5.2 Breathing apparatus (BA) selection chart for protection against asbestos in air

PFFresh-airhose BA BS
EN 138/269

Light-duty
compressed
airline BA
masks BSEN 12419

Light-duty
compressed
airline BA
hoods,
helmets,
visors BS EN
1835

Constant
flow
compressed
airline BA
hood BSEN 270/271
Mask BS EN
139

2000

200
40

Suit
Full-face
mask
Hood

20

LDM3

LDH3

Hood
Blasting
helmetFull-face
mask

LDM1
LDM2

LDH2

Half-mask

Table 5.3 Worked example

Work:

Removal of asbestos insulation from a boiler house

Type of asbestos:

Representative samples taken from the lagging to be removed and the occupier’s
documentation about it indicate that the lagging contains chrysotile (whiteasbestos) only

Control limits:

0.3 f/ml for 4-hour time weighted average (TWA) and 0.9 f/ml for 10-min TWA asprescribed in CAWR

Propsed type of
removal:Well-conducted, controlled wet stripping using manual tools. Representative coresamples taken after the wetting process at an earlier job indicated that it is unlikely
to hit a dry patch. Same procedure will be conducted to ensure similar situation inthis work. Wetting to be done using injection needles, wetting agents and water

Amount to be removed:

8 m2 of asbestos-containing lagging material

Likely residual fibre inconcentration in air:Up to 1 f/ml (Table 1.1) and this figure agrees with the exposure monitoring results
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Table 5.3 Worked example (continued)

Work activity:

Have to work around and in between pipes. Removal workers will have to pass in
between pipes and girders (both vertically and sideways). Adequate time and person
resources have been planned in for stripping, cleaning and decontamination activities. The
effort required – moderate work. Working on a cold plant. The work environment is not a
confined space and will contain normal levels of oxygen. No need to use solvents, gluesetc

RPE wearers:

Clean shaven except for one person who has beard; no unusual facial marks; nospectacle wearers

Other PPE:Type 5, category 3 coverall (see paragraph 5.35) to protect against asbestos penetration.
Gloves and safety boots in accordance with RA requirements

Protection
required:

Minimum protection required from suitable RPE to reduce exposures to the control limit of
1/0.3 = 3.3 (ie likely residual fibre concentration in air divided by 4-hour TWA control limit).
This calculation indicates that it would be possible to use devices with a PF of 4. However,the law requires that inhalation exposure to asbestos fibres is reduced to the lowest levelreasonably practicable. Therefore, it is necessary to consider devices which could offer thebest possible protection

Selection ofsuitable RPE:

From Table 5.2 – Types of RPE which offer highest PF (2000) are self-contained breathingapparatus (SCBA) with positive-demand full-face mask and compressed airline-breathingapparatus (CABA) with positive-demand full-face mask(a) SCBA is not suitable because it will not last for more than 15 minutes of actual 		
stripping work. Safe usable time for SCBA will include time required for decontaminationand exit to a safe area. SCBA would be too bulky to use in the likely restricted space;it will introduce unnecessary strain on the wearer and may cause other safety-related
accidents(b) In this situation it is not reasonably practicable to use CABA because air supply hoses
can become entangled during use. This may introduce tripping hazards and may 		
present considerable secondary exposure problems during disconnection to enter
the decontamination area. During the decontamination of hoses, asbestos on hose
protective coverings may contaminate the decontamination area. For these reasons it
is considered that CABA is not suitable for the work to be undertaken(c) The next choice of device is respirators. Respirators with the highest PFs (Table 5.1)
are non-powered full-face mask with P3 filter(s), TH3 powered hoods and TM3 power
assisted devices with full-face masks and P3 filter(s). A non-powered device would
be uncomfortable and would place demand on the user’s lungs when compared to a
powered device. So a TM3 power-assisted respirator with full-face mask and P3 filter(s)would be the choice for those without beards. This RPE, when used in conjunction witha suitable RPE programme, should reduce the exposure concentration to below 0.02 f/
ml. This concentration is near the clearance level(d) All our wearers, except the person with the beard, were quantitatively fit tested for a
power-assisted respirator with full-face mask (TM3) – model 123 made by ZZ Ltd. In
this work situation, the person with the beard could be provided with a TH3 powered
hood. If the power to the device fails completely during use, the wearer should be able
to exit the work area quickly and without significant danger to life or health

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5.18 To obtain adequate performance during use, the selected RPE should beworn correctly every time. This means that the user should carry out a fit check on
every occasion that a mask is worn to ensure that a good fit has been obtained.
Beards, sideburns and even stubble or wearing glasses will affect the face sealof tight-fitting face masks which rely on a close contact between face and mask.
Employees wearing RPE relying on a tight face fit should be clean shaven. The
expected level of workplace protection provided by suitable RPE is shown by thePF values in Tables 5.1 and 5.2.
5.19
n
n
n
n
n

A repeat fit test should be conducted where the wearer:

is changing to a different model of RPE or different sized face mask;
loses or gains weight;
undergoes any substantial dental work;
develops any facial changes (scars, moles etc) around the face seal area; orif the company’s health and safety policy requires it. It is recommended that
employers have a specific policy on frequency of repeat fit testing, eg every one
or two years.

5.20 For workers who cannot wear a tight-fitting facepiece, equipment that
does not rely on a good face seal for protection should be provided, eg poweredor air-supplied hoods, and powered or air-supplied blouses. For workers who
normally wear glasses, there are two further options: wearing contact lenses inside
a standard full-face mask or to wear a full-face mask which permits the fixing ofspecial frames inside the facepiece.

Care, maintenance and testing of RPE
Looking after RPE
5.21 The RPE must be checked to ensure it is clean and in good working
order before it is given to the wearer, and before it goes back into storage. Badly
maintained RPE will not provide adequate protection and the wearer’s health will be
put at risk. Before use, checks, where appropriate, should be made on:
n
n

n
n
n
n
n
n

the condition of the head harness, and the facepiece including seal and visor;
the condition of the inhalation and exhalation valves, where fitted. For example
dirty, curled-up or cracked valves will not perform properly and will severelycompromise the protection provided;
the condition of any threaded connectors and seals;
the condition and type of filter(s), that they are ‘in-date’ and fitted properly;
the battery charge/condition;
the airflow rate for power-assisted and powered respirators compared with the
manufacturer’s specification – before the device is used;
whether the RPE is complete and correctly assembled; andany additional tests in accordance with the manufacturer’s instructions.

5.22 In addition to the pre-use checks detailed above, all RPE (except thedisposable type) should be more thoroughly examined and tested, by trained
personnel, before it is issued to any wearer for the first time and at least once amonth to make sure that it is working properly to its design specification. A recordof inspection, examination, maintenance and defects remedied must be kept forfive years. Only proprietary spare parts should be used.
5.23 The manufacturer of RPE should give instructions on its cleaning andmaintenance. The procedures should be followed. After each use, RPE (except thedisposable type) should be decontaminated, cleaned, disinfected, inspected andplaced in suitable storage specifically provided for that purpose.
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Air quantity and quality
5.24 Where breathing apparatus is used, the flow rate and pressure of the air
supply should be checked at the start and end of each shift. Also, wearers should
check these at regular intervals during the shift. Air supplied to breathing apparatus(BA) should meet minimum quality requirements. These are given in British
Standard BS EN 12021.25 The RPE or air compressor supplier should be able toadvise on how to meet these requirements.

Do not modify any form of RPE without the knowledge and consent
of the manufacturer
RPE training for employees, including supervisors
5.25 Employees should be given adequate instruction, information and training
on the following:
n
n

n
n
n
n
n
n

how to fit and use the RPE correctly;
why they must wear the RPE correctly and the importance of fit testing for the
initial selection of suitable equipment and pre-use fit-checking each time it isworn;
why they should never take off and/or put down RPE in a contaminated area,
except in a medical emergency;
how to recognise a reduction in air flow and what to do if it happens;
why a particular type of RPE has been selected, and what it can and cannot
do;the manufacturer’s instructions on the use and maintenance of the equipment;
how to clean contaminated RPE when leaving the work area; andwhen not in use, where and how to store the RPE.

5.26 Employees should receive regular refresher training (at least once a year) on
the use of RPE. It should not be assumed that, because workers have worn
RPE before, they will always use it properly.
Supervision
5.27 The competent supervisor should monitor the use of RPE to ensure that it isworn properly. For instance, the supervisor must make sure that wearers never:nnmisuse equipment (examples of misuse and common mistakes are listed
below); or
remove their RPE in a contaminated area – not even for a moment, except inan emergency (eg medical, accidental damage to RPE).

5.28 It should be standard practice for supervisors and wearers to check that the
RPE is in good working order (before wearing it) and that it is being worn correctly.
Some common misuses of RPE when working with asbestos
5.29 The examples below indicate some of the very serious misuses of RPE.
Misuses of this kind will always result in reduced protection and unnecessary, andpreventable, exposures to asbestos fibres. These misuses invalidate the suitabilityof RPE and constitute a failure to comply with CAWR.

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Figure 5.1 Misuse of RPE

Figure 5.2 Misuse of RPE

All types of RPE
n Wearing of disposable respirators, half and full-face masks by people with facial
hair which prevents an adequate seal being achieved.
n Wearing safety goggles or spectacles which are not compatible with thedisposable respirator or a half-mask. Incompatible goggles will prevent anadequate seal being achieved.
n Failing to ensure that the RPE fits the wearer.
n Working in a contaminated area while the respirator is left hanging around theneck.
n Using the RPE if it is dirty, damaged or incomplete.
n Failing to properly maintain the RPE.
n Leaving the mask lying around in the workplace – dust will get inside and thewearer will breathe it in the next time it is put on.
n Wearing the coverall without the hood in position (see Figure 5.1).
Disposable respirators
n Wearing the respirator upside down.
n Failing to adjust the nose clip to obtain a good face-fit and face seal.
n Not using the two head straps correctly.
n Working in a contaminated area while the respirator is left hanging around theneck or placed on top of the head.
RPE with full-face masksn Failing to adequately tighten all the head harness straps.
n Wearing ordinary spectacles with a full-face mask. There are special frames
which can be fitted inside the mask which do not interfere with the face seal.
n Wearing the head harness over the hood of the coverall – this can cause
slippage of the mask and loss of the face seal (see Figure 5.2).
n Failing to ensure that the correct filter is fitted in the filter housing, or that seals/
O-rings are in place and correctly seated.
n Failing to ensure that filters are present in their housing.
n Failing to tighten the breathing hose to the face mask and filter housing.
n Failing to test the airflow.
n Failing to replace worn and distorted masks.
n Failing to test the voltage and capacity of batteries, and to replace inadequateones.
n Keeping working if the fan stops or the flow rate falls – leave the work area
immediately.
n Using filters not approved for the device.

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Coveralls
5.30 Coveralls should be worn whenever an RA indicates there is a possibility ofcontamination with asbestos fibres. Therefore they should be worn during:
n

n
n
n
n

preparation of the work area including pre-clean and construction of theenclosure (unless the preparation work does not involve any potential forasbestos contact or contamination);the preparation and use of controlled stripping equipment;
any work involving the removal or repair of asbestos;the four-stage clearance; andthe dismantling of the enclosure and residual clean up.

5.31 Coveralls may also be needed for other activities, where the potential forcontamination exists, eg inspecting roof voids or undercrofts when preparing
tenders.
5.32 Non-disposable (eg cotton) and disposable coveralls can be used.
Disposable coveralls tend to be more popular as there are few laundries now
accepting asbestos-contaminated items for washing. It is also easier to double bag
disposable overalls and dispose of them as asbestos waste, either on site, where
there are facilities, or at base. Cotton coveralls should be decontaminated in a
specialist laundry after use (see paragraph 8.43).
5.33 Disposable overalls vary significantly in quality and, although they are
generally only used for one shift or less, it is important that good quality disposable
overalls are used. Poor quality overalls:nntear easily, allowing contamination of the operative’s body; andallow permeation of fibre through the intact material.

5.34 Contamination inside the coverall increases the potential for operator
exposure and further spread of asbestos. Disposable overalls should therefore
be selected that are robust enough and large enough to allow free movement
throughout the enclosure. It is good practice to wear one size too big, as this can
reduce ripping and tearing at the seams.
5.35 A Type 5, category 3 disposable coverall will provide such protection. Type5 relates to draft standard BS EN ISO 13982-1,26 and category 3 (CE complex;
risk of serious or mortal danger) is in accordance with the Personal Protective
Equipment (PPE) Regulations 1992.27
5.36 The coveralls should have elasticated cuffs or be sealed with tape. In
addition, coveralls should be worn in such a way as to reduce the ingress of dust
inside the garment. The ingress points are at the head and feet. The coverall hoodshould be worn over the straps of the RPE and the coverall legs should be wornover footwear, ie do not tuck legs into the boots as dust and debris will get in at
the top.

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Chapter 6: Enclosures for workwith ACMs

SummarynnnnThe planned work area, immediate surrounding area and waste/transit routes
should be checked to see whether a pre-clean is needed.
Enclosures– Are required unless the level of risk is likely to be low, the location is remote,or an enclosure is not practical.
– Should be constructed of 1000 gauge polythene.
– Should be connected directly to the DCU where possible.
– Should be placed under negative pressure.
– Should have viewing panels (size at least 600 mm x 300 mm).
– Should have a sacrificial flooring.
– May require additional protection, eg for weather protection, or be fireretardant.
Airlocks and baglocks– Should be of an appropriate size for the number of personnel and amount ofequipment (dimensions at least 1 m x 1 m x 2 m (height)).
– Should have a viewing panel on the inner stage (size at least 600 mm x
300 mm).
NPUs– Should provide a slight negative pressure of 5 Pa.
– Should provide a constant flow of fresh air through the enclosure.
– Should be sufficient in quantity and placed correctly to prevent ‘dead spots’and ‘short-circuiting’.

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Contents
Introduction

89

Definition and use

89

When is an enclosure required?
Preliminary planning 91

89

Enclosure design and main features

91

Enclosure size 91
Sealing the enclosure 92
Enclosure extraction (negative pressure)
Enclosure access 93
Viewing panels 96
Occupied buildings 96
Securing external enclosures 97

93

Site preparation and construction of enclosures
Site preparation and pre-clean 97
Construction of the enclosure 98

Air extraction equipment

97

100

Testing, monitoring and maintenance

105

Visual inspection 105
Smoke testing 106
Differential pressure monitors 106
Viewing panels 107
Air monitoring 107
Testing and maintaining air extraction equipment 107

Dismantling and disposal

108

Emergency procedures 109

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Introduction
Figure 6.1 Enclosure withthree-stage airlock

6.1
Enclosures are a fundamental component in the control of asbestos
materials during removal work. This chapter explains the function and purpose of
enclosures and gives practical advice on their design, construction and use during
work with asbestos. Enclosures are normally required to:nnprevent the spread of asbestos (CAWR, regulation 15); andprevent the exposure of other people (employees and others) (CAWR,
regulation 10) who may be affected by the work.

Definition and use

Figure 6.2 Work without
an enclosure

6.2
An enclosure is a physical barrier employed around the asbestos work area
which will contain asbestos dust and waste arising from the work and which will
also prevent the spread of asbestos materials to the surrounding environment. It is
designed to prevent the spread of airborne fibres and dust and also to prevent the
spread of surface contamination during all the activities associated with asbestos
removal, including waste handling and bagging, and cleaning.
6.3
Access to the enclosure is regulated through entrance and exit openings(known as airlocks, see Figure 6.1). The airlocks are an essential feature of theenclosure, allowing the controlled movement of personnel, waste and equipment
in and out of the work area and also enabling the decontamination of personnel,
equipment and waste items on exiting the unit. Airlocks are also used forchanging, where transiting procedures are employed (see paragraphs 8.13-8.15).
The enclosure and airlocks should be airtight and under mechanical extraction
ventilation.
6.4
Enclosures by design and function will lead to increased amounts of dust
and debris inside the area. Anyone entering or working inside an enclosure mustwear suitable protective clothing and RPE, and must thoroughly decontaminate
themselves on leaving the enclosure. Further information on personal protection
and decontamination procedures is given in Chapters 5 and 8 respectively.
When is an enclosure required?
6.5
Work on the most hazardous forms of asbestos (ie those which require alicence to work on: asbestos insulation, asbestos coatings and AIB will normallyrequire an enclosure. These ACMs include asbestos thermal insulation (such as
boiler and pipe insulation, and sprayed asbestos applied for fire protection, anticondensation and acoustic control), and AIB products such as ceiling tiles or
panels or boards containing asbestos. The enclosure will be required irrespective of
the nature of work location (such as in buildings, ships and other structures) or thesize of the premises.

Enclosures are needed to control the spread of airborne or surface
contamination. Whenever this is likely, an enclosure is needed
6.6
Enclosures are also necessary in situations where, although the work may
have primary controls (eg glove bags), the consequences of a control failure would
be significant in terms of contamination or risk, so there needs to be secondary
containment. This means that an enclosure will be required in most situations, butthere will be some exceptions, including for ACMs which normally require a licence(see paragraphs 6.7-6.8).

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6.7
Enclosures are not generally required for work with non-licensed asbestos
products, such as cement materials, eg corrugated roofing sheets and building
panels (see Figure 6.2). Asbestos cement items normally present lower risks.
Precautions for work with these materials are described in the HSE guidancebooklet Working with asbestos cement.3 However, there may be occasions whenan enclosure is needed for asbestos cement. If the asbestos cement is extensive
and difficult to remove, resulting in much breakage and debris, or the work is close
to occupied or sensitive areas, then an enclosure may be needed.
6.8
Enclosures would also not be necessary for licensed products in certain
circumstances. For example where there are practical difficulties in constructing
an effective enclosure or the location is very remote. In addition, an enclosure
will not be required for minor work with licensable materials, eg certain types ofshort duration or low risk work where an asbestos licence is not needed. Details
on these types of activities and the necessary precautions are given in the HSE
guidance booklet Asbestos essentials task manual: Task guidance sheets for thebuilding maintenance and allied trades.2 Asbestos essentials is primarily targeted
at tradespeople carrying out one-off jobs. If licensed asbestos removal contractors
carry out similar one-off tasks, these procedures are appropriate. However, if thework areas are larger or the task is repetitive, an enclosure will be required. An
enclosure would also not normally be required in dealing with minor contamination
situations where the asbestos is only present as loose debris or dust. An enclosure
would also not be expected in external situations involving building rubble, soil orcontaminated land.
6.9
The scenarios where an enclosure may not be required can be summarised
as follows. These will be determined in the RA for the work, taking into accountthe likely risks, and the practicalities and costs involved. Enclosures may not be
required if:
n

n
n

n
n

the level of risk is low because the operations are very small scale and of shortduration. When considering the level of risk you should consider the potential
for fibre release and the spread of surface contamination;
the location is extremely remote, where the risk to employed people ormembers of the public is negligible;
the work is at height and an enclosure is not practical due to the height orcomplexity of the structure (eg pipework in the open air at high level), or its
exposure to severe weather conditions;
it is a situation where there are practical difficulties in obtaining an effective sealon the structures, eg soffits around building roofs;
cleaning up minor contamination or external contamination.

Remoteness by itself is not a reason to justify the absence ofan enclosure
6.10 If an enclosure is not a reasonably practicable option, remember that a key
component in the control of asbestos and in the controlled movement of personnel,
equipment and waste will be absent. The absence needs to be compensatedfor and alternative arrangements employed. In such cases, the boundaries of thework area should be clearly marked by suitable warning notices and by physicalobstructions such as ropes or barriers. Such segregation measures should beplaced at a distance away from the work and not immediately next to it. In addition,in the absence of an enclosure, particular emphasis has to be placed on work
methods and procedures which minimise dust generation and prevent the spreadof contamination. Reassurance air sampling may also be required. There will stillneed to be arrangements to regulate the movement of personnel equipment andwaste from the designated work area and to carry out preliminary decontamination
procedures and waste bagging. Full decontamination facilities (ie a hygiene unit) will
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be necessary in most cases (the exceptions are likely to be Asbestos essentials2
scenarios and cleaning up contamination). A certificate of reoccupation will also be
required in most situations (again with similar exceptions) although clearance air
monitoring will not be necessary in external locations (see paragraph 6.67).
Preliminary planning
6.11 The enclosure is a key feature in the control of asbestos during removal
work. It has to be designed properly and it has to operate effectively for theduration of the work. These are matters to be considered in the very early stagesof work planning and they should form part of the RA process. The enclosure will
be deployed in many different situations and conditions so, while there are many
common features of the enclosure, irrespective of where it is used, it has to be
designed specifically for the particular circumstances of the individual job. The
factors to be considered for all uses are as follows:
n
n
n
n
n
n
n
n
n
n
n
n
n
n

clearance of the work area;
removal of ‘mobile’ items;
the need for a pre-clean;
the size and shape of the work area;
the enclosure will be as airtight as possible;
plant is switched off (eg boilers) after liaison with the client;
there will be sufficient and uniform negative pressure (without short circuiting)within the enclosure and airlocks;
there will be sufficient air movement through the enclosure;there will be safe and easy access for personnel, equipment and waste;
the enclosure will be robust for the conditions;security and prevention of damage;provision of viewing panels;
actions to take in an emergency;
the need for fire prevention materials (eg fireproof polythene).

6.12 There are other matters which may have to be considered in somesituations, such as:nnwork in occupied buildings;
securing external enclosures.

Enclosure design and main features
6.13

An enclosure typically consists of the items in Figure 6.3.

Enclosure size
6.14 The enclosure should be designed around the location of the asbestos to be
removed and the access requirements. It should be big enough for the work activity
and there should be reasonable working space. The dimensions should takeaccount of the number of workers involved and the size and shape of the items or
materials to be removed and the need for any plant or equipment to be used. Items
to consider include lengths of pipework, and plant such as scissor lifts or platforms.
The enclosure should not be oversized, as it increases the spread of asbestos andthe size of the area to be cleaned. It also increases the ventilation requirement.
6.15 Enclosures may either make use of parts of the existing building structure or
be self-supporting temporary structures purpose built around the asbestos working
area. Existing rooms or walls, ceilings and floors can be used where possible toprovide part or all of an enclosure. The surfaces of the enclosure, irrespectiveof the composition, should be smooth and impervious. If any existing surface is
unsuitable, eg it is rough, damaged or friable, it should be pre-cleaned and thenAsbestos: The licensed contractor’s guide

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lined with a material such as polythene sheeting. The integrity of the enclosuremust also be maintained as work progresses. For example when AIB ceiling tiles
are removed opening the ceiling void. The ‘void’ will become part of the enclosure.
It will need to be smoke tested and the area volume included in the ventilation
calculation. It may be possible to seal such areas as work progresses. Howeverthese areas will need to be cleaned and subject to clearance procedures.
Sealing the enclosure
6.16 The enclosure should be effectively sealed and as airtight as possible. Allleaks should be identified and sealed. Sealing should be undertaken at all joints
and corners, particularly in purpose-built structures and at all windows, doors,
ventilation grilles, airbricks, inlets, exhausts as necessary. Particular attention shouldbe paid to closing any gaps or holes around pipes, ducts, conduits, structural orother items (including inside cupboards or units) that pass through to adjoining
rooms or floors. Openings should be sealed using a combination of materials suchas tape, proprietary sealing compounds (eg expanding foam) (see Figure 6.4) andimpervious sheeting. Foam should be trimmed to size after setting. If complete
sealing is difficult to obtain, then additional controls should be employed. These can
include mini-enclosures within large enclosures, glove bags and enhanced negative
pressure.

Figure 6.3 Schematic diagram of the main elements of an enclosure
Enclosure

Airlock

NPU
Viewing panels
NPU

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Figure 6.4 An enclosure
sealed with expanding foam

Note: The use of certain foams and adhesives in very confined spaces, on hot
pipework or close to the breathing zone may cause high concentrations of harmful
vapours and should be avoided. The use of any sealant or adhesive should beconsidered in an RA to establish the risks to health and the appropriate controls
and protective equipment. Also if some foams were to remain after completion of
the work, it may have implications for fire regulations.

The enclosure should be constructed before any work on the ACMs,
including placing of injection needles, is carried out
Enclosure extraction (negative pressure)6.17 There should be sufficient negative pressure (ie mechanical extract
ventilation) within the enclosure and the pressure should be as uniform as possible
throughout the unit. Air extraction should not be seen as an alternative to awell-sealed enclosure. Its functions are to provide additional control if there areaccidental leaks and to control air movement during personnel and waste transfers
to and from the enclosure.
Figure 6.5 An NPU

6.18 The pressure differential will depend not only on the extracted air rate fromthe enclosure, but also on the physical size and shape of the structure, the extent
of leakage (ie the effectiveness of the sealing) and external weather conditions,eg a change in wind direction can positively pressurise an enclosure. Where large
extensive plant or long stretches of pipework are to be stripped of asbestos, it may
be appropriate to sub-divide the space into a number of smaller enclosures, rather
than to treat it as a single unit. It may be difficult to achieve good negative pressure
for extremely large enclosures (eg those used in power stations), although the
NPUs (see Figure 6.5) will help to achieve some airflow near work areas, even if notproviding good negative pressure.
6.19 Also, where the work area is complex or consists of a series of rooms(eg in office blocks or hotels) there will be potential difficulties in achieving auniform negative pressure. Again, in these cases there should be several smaller
enclosures. In some situations, it will be beneficial to have smaller working
enclosures built around the specific items to be stripped. In situations where
negative pressure is difficult to achieve, over-extraction may compensate but theextraction level should not damage the integrity of the enclosure (see paragraph6.47). In addition, if stripping involves opening up other parts or sections of thepremises, eg in removal of ceiling tiles or dividing walls, the ventilation rate should
be calculated on the basis of the final enclosure volume, ie the initial area and theceiling void. Air movement is discussed in more detail in paragraphs 6.41-6.47.

Figure 6.6 DCU attacheddirectly to an enclosure

6.20 Air movement in the enclosure should be designed to ensure that there isuniform airflow as far as possible in all areas. NPUs and supplementary air inlets
should be located to achieve good flow and to avoid dead spots (see paragraph6.42). Air movement should be checked during the smoke test (ie checking thatsmoke is cleared efficiently from all areas of the enclosure) and by using smoke
tubes and/or differential pressure monitors.
Enclosure access6.21 All enclosures should have means of access for personnel, plant andequipment, and the removal of asbestos waste. Openings for these purposes
need to be constructed in a manner which prevents asbestos dust escaping into
the general environment. Asbestos workers should enter the enclosure from thehygiene facility, which should be attached via a short intervening space or tunnel
to the enclosure wherever practicable. This is shown in Figure 6.6. This is thepreferred arrangement. Where the hygiene facility cannot be positioned close to
the enclosure, a transiting system is required. Transiting systems are much more
complex and should be avoided where possible. However there will be many
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Figure 6.7 An airlock usedin transiting

occasions when their use is necessary. In transiting systems, workers will enter theenclosure via a three-stage airlock. The airlock is shown in Figure 6.7.
Information on the procedures for transiting and for using hygiene facilities is given
in Chapter 8.
6.22 Enclosures should be designed and constructed with separate
arrangements for the removal of asbestos waste. A system of airlocks (calledbaglocks) similar to the transit facilities can be used for the removal of wasteasbestos from the enclosure. The design of the baglock system is shown in
Figure 6.8. In those circumstances where a separate airlock and baglock systemcannot be employed, a hybrid arrangement should be used. The design of thehybrid system will depend on whether the hygiene unit is connected directly to theenclosure or whether a three-stage airlock is involved (ie transiting). The various
options are shown in Figures 6.9 and 6.10. The arrangements and procedures forcleaning, labelling and transferring waste bags are described in Figure 6.8 andBox 7.6.

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Figure 6.8­  Typical design of three-stage baglock for removal of waste from an enclosure

Double bagged
waste stored
here, awaiting
removalTo outside

Bags put into
second bags,
excess air
removed, andagain cleaned
externallyBags cleaned
externally by
wiping down

Enclosure(Bags filled in
enclosure andsealed)NB If separate baglocks and airlocks are used, normally
only one should be open and in use at any time

Figure 6.9 Airlock/baglock arrangement where the enclosure is directly attached to the DCU and there is limited space

Hygiene unit

Clean

ShowerDirty

TunnelOne stage

Enclosure

NPU

Baglock

Figure 6.10(a) Airlock/baglock arrangement where transiting is involved and there is limited space

Threestage
airlock

Enclosure

NPU

Three-stage
baglock

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Figure 6.10(b) Airlock/baglock arrangement where transiting is involved and there issufficient space

Threestage
airlock

Enclosure

NPU

Threestage
baglock

Asbestos waste bags should not be taken through thehygiene facility
Figure 6.11 Viewing panel

Viewing panels
6.23 Suitable clear perspex ‘viewing panels’ must be included in the walls of theenclosure so the site supervisor can see what is going on inside without having
to enter (see Figure 6.11). This helps ensure that the method detailed in the POW
is being followed. The number and location of these panels will depend on thelocation, size and complexity of the enclosure (see paragraph 6.37). Viewing panels
should be employed in the inner stage of airlock and baglocks. Where viewing
panels are impractical, organisations should use alternative methods to observeand monitor progress within the enclosure. Camera (eg CCTV) and computer
webcam systems can be used. Miniature colour cameras/transmitters are now
available and can be linked to a receiver and monitor or TV. Hard-wired systems
are also available. Cameras can be placed in appropriate locations. The typesof circumstances where camera systems should be used include undergroundlocations, multiple-floor buildings, existing buildings where panels cannot be
installed, enclosures where work location is obscured or remote from the viewing
panels. Cameras should be protected for ease of cleaning (eg sheeted over).
Occupied buildings
6.24 If other parts of the building are to be occupied during asbestos removal
then particular care and attention will be needed to ensure that the work does notpresent any risk to the building occupants. Additional safeguards and checks will
be required. Visual inspections and airborne sampling outside the enclosure will
be necessary to confirm the effectiveness of the control regime (see paragraph6.56 and Box 6.1). It will also be necessary to identify and prevent or resolve any
additional hazards introduced by the enclosure, eg if it obscures or blocks any
fire exits. Where this is unavoidable, alternative arrangements should be madeand clearly communicated to the building occupants and the asbestos removal
workers. Fire alarms should be able to be heard from inside the enclosure.
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6.25 It will also be necessary to ensure that occupancy or operation of any
processes or building services does not adversely affect the performance of theenclosure. Checks should be made to ensure that mechanical air movement within
the building does not compromise the negative pressure inside the enclosure, andalso that process emissions are not drawn into the enclosure. For example movementof lifts will cause changes in air pressure. The effects of any building processes
and the impact of air conditioning, location of lift shafts or air heating systems alsoneed to be considered. Take care to ensure that existing ventilation systems are notcontaminated, eg through inappropriate siting of NPU discharges near to ventilation
intakes.
Securing external enclosures
6.26 Enclosures must always be properly secured to prevent toppling or falling
over. This is particularly relevant for external units which are subject to the vagariesof the weather. Enclosures should be securely attached to the building itself or
onto scaffolding. Consider the security of the enclosure to ensure unauthorised
personnel do not enter.

Site preparation and construction of enclosures
Site preparation and pre-clean
6.27
Before any work starts (including erecting the enclosure), the DCU should
be set up and operational. An assessment should have been completed toestablish the PPE and RPE required for the initial preparation work and constructionof the enclosure. The proposed work area should be inspected and checked toprepare for the removal work. The main purpose of the inspection is to identify theneed for a pre-clean, prepare the site for work (eg by sheeting or removing items,
ie a ‘soft strip’), and to deal with matters which may cause difficulties in obtaining
clearance certification (eg remaining ACMs, wet floors etc). The site pre-workinspection should be performed in the areas where clearance will be required, ie theplanned enclosure area, the relevant surrounding places such as transit and wasteroutes, and the area immediately next to where the enclosure will be located.
6.28 If there is any evidence of minor ACM debris or dust then a pre-clean
should be undertaken (but note 6.30 and 6.31 regarding significant contamination).
All the loose material should be cleaned up before the enclosure is constructed.
The pre-clean should be undertaken using appropriate dust suppression andcontrol measures, including vacuuming with a type H vacuum cleaner, surface
wiping, temporary encapsulation with polyvinyl acetate (PVA), tape or cling film,
spray wetting and bagging. It is also advisable to carry out a pre-clean if there is
non-asbestos dust and debris present. This material can be disposed of as normal
waste. Otherwise once the work starts, the material will be considered as asbestos
and will have to be removed as hazardous waste (see paragraphs 7.87-7.101).

A pre-work visual site inspection should be carried out to determine
the need for a pre-clean of the area to be enclosed and immediatesurrounding areas
6.29 The work area should be free from items of plant, equipment and furniture
as far as possible. All mobile or portable items should be removed before theenclosure is constructed. Any items remaining, eg plant or electrical equipment
should also be pre-cleaned and then protected or covered with polythene sheetingand securely taped to complete the seal to prevent contamination. If there areboilers, or similar plant incorporating flues, inside the enclosure, the flues should
be sealed to prevent the spread of asbestos. The inclusion of live operating plantwithin the enclosure will only be allowed in exceptional circumstances
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eg combustion air requirements on active boilers will need to be considered.
Similarly, floor surfaces or areas which may be difficult to decontaminate (eg earth
floors, behind and below radiators and pipes) or will generate dust during cleaning(eg concrete) should be pre-cleaned and then protected.
Construction of the enclosure
6.30 The enclosure should be designed and constructed so that asbestos
materials are not disturbed until it is complete. This is particularly important where
there is extensive contamination of the floor and other surfaces.

The hygiene unit should be set up and fully operational before work
starts. This includes any work involved with erecting the enclosure
and pre-cleaning asbestos or suspect asbestos contamination
6.31 In situations where the work is being undertaken in premises where there issignificant contamination (eg due to an incident) and the enclosure cannot be built
to encompass the material, then the loose visible asbestos dust and debris andother items should be removed before the enclosure is constructed. The pre-clean
should be done using appropriate dust suppression and control measures (seeparagraph 6.28).
6.32 Construction and composition of the enclosure will depend on various
factors, including the extent of use of the existing building structure, the duration of
the job and the location of the work. Where it is possible and feasible, the existingparts of a building may be used. This can have benefits in time and possibly in
reducing the potential for leaks. All openings (vents, doors, windows, holes etc) will
have to be sealed. However, using an existing building may present practical issues
in terms of siting ventilation plant and airlocks, and in the provision of viewing
panels.
6.33 The most widely used form of enclosure is a self-supporting temporary
unit built to accommodate the work area. These consist of a frame to which
sheeting material is securely fixed. Polythene sheeting is one of the most widelyused materials for enclosures, providing a flexible, impervious and easily erectedbarrier. It needs to be thick enough to withstand the wear and tear of the job. For
most situations, opaque sheeting of nominal 1000 gauge (250 microns) should be
sufficient. Where there are fire hazards, eg in power stations or from process plant,orange fire-retardant polythene should be used. In exposed locations, polythene
sheeting may not have sufficient strength, so alternative materials such as polyvinyl
chloride (PVC) sheet reinforced with woven nylon mesh can be considered. Where
solid barriers are needed, suitable panels or wooden board can be used, lined
internally with polythene sheeting.
6.34 The most widely used method of supporting the sheeting material is bytimber framework. The size of the timbers used in the supporting framework
will vary depending on their unsupported length, but they need to be of suchdimensions to provide adequate fixing and support for the sheeting material.
Timber width of 50 mm x 50 mm should be sufficient for internal work. Timbershould also be clean. The sheeting should be secured to the timber using staples,tape and spray tack. Scaffold frameworks with internally fixed scaffold boards may
also be used if they are rigidly connected to the structure or properly designed tobe free-standing. Proprietary designed frameworks of metal or plastic pipe, angle,
channel etc, can also be used.

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6.35 If a scaffold framework with internally fixed boards is used, the sheeting
material should be fixed to the inside of the supporting framework. Where a timber
framework is used, the sheeting can be attached to either side of the timber. But,
note the following points:nn

if it is attached to the outside, asbestos fibres may be retained on or behind theframework, so it needs to be either protected against contact with asbestos (egby taping up the timber/sheeting joins) or the framework and its interface withthe sheeting scrupulously decontaminated after use;
If the polythene sheeting is attached to the inside of the timber, it will needreinforcing, as this is an inherently weaker attachment under negative pressure.
More timber should be used in the framework and there should be a greater
frequency of staples; the staples should be taped over (using fabric tape) andthere should be continuous use of fabric tape at the timber/polythene contact.
This arrangement eliminates the potential for dust and debris to be trapped
between the timber and sheeting.

6.36 All joints in the sheeting material need to be adequately sealed. Where
adhesive tape is used to seal joints on polythene sheeting, it is preferable to apply it
to both sides of the joint. Vinyl tape is suitable where an enclosure is only expected
to be used for a relatively short period, but if enclosures are to be left in position fora longer period, fabric-based tape (eg 75 mm width polycloth) is more effective.
6.37 The enclosure should contain a sufficient number of viewing panels (and/or CCTV or webcam systems) to allow all parts of the enclosure to be visible fromthe outside. The clear plastic panels should be inserted into the sheeting during
construction. Panels should be taped on both sides. Panel size should be at least
600 mm x 300 mm unless it is impractical and the panels should be located at aconvenient height for viewing (eg about 1.5 m from the floor surface).

The airlocks and baglocks should be at least1 m x 1 m x 2 m (height)

Figure 6.12 Flap
arrangements for airlocks

6.38 Airlocks and baglocks should be as big as possible to allow the necessarychanging, cleaning and transfer activities for workers and waste items and bags.
The airlocks and baglocks should be at least 1 m x 1 m x 2 m (height). This is aminimum size. They will have to be bigger in situations where larger items of waste,such as sections of piping, ducting or board, are being removed. Where space isrestricted in one direction, eg along a corridor, the airlocks and baglocks should
be extended in the other direction (eg 0.8 m x 2 m x 2 m). Separate airlocks andbaglocks should be used where space allows.
6.39 Airlocks need to be constructed with access openings between eachcompartment which prevents asbestos dust passing from one compartment to
the next. This is usually achieved by cutting vertical slits in the sheeting and by
fixing polythene sheets across the opening (see Figure 6.12). This vertically shaped
opening is then reinforced at the top. The vertical sheet needs to be placed on
the enclosure side of the partition with an adequate overlap so that air can moveinwards but outward air movement is restricted. Smoke testing will demonstratethat this is effective. The bottom of the inner flaps should be weighted down to
improve control of airflow by the addition of a timber or metal bar, or a length ofchain which allows flexibility in all directions. As airlock flaps are used frequently,
they should be made from heavy gauge material such as nominal 1000 gauge
sheeting. Various proprietary designs of airlock are available, but some types do not
permit the flow of an adequate supply of replacement air. Where these designs areused, separate means of providing replacement air may be needed (see paragraph6.42). An adequate supply of replacement air into the enclosure is essential (seeFigure 6.14). The outer compartment should be fitted with a further vertical sheet (aAsbestos: The licensed contractor’s guide

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security sheet on the outside) which is used to cover over the entrance at the endof the shift. It should be taped back onto the roof area when the airlock is beingused.
6.40 The floors of enclosures need to be covered in an impervious material
unless the existing floor, on which the enclosure is erected, has an impervious
surface which can be thoroughly cleaned after asbestos removal work iscompleted. Floor coverings may become slippery. If polythene is used, it canbe covered with hardboard, or similar material, to minimise this risk. But, where
hardboard or similar materials are used, they need to be disposed of as asbestos
waste.

The floor of the enclosure should be covered in an impervious layer
Air extraction equipment
6.41 Whatever the type of enclosure, it is important to remember that noconstruction method will give an absolutely airtight seal and that some degreeof leakage will always be present. For this reason, mechanical extract ventilationneeds to be applied to maintain the air pressure inside the enclosure slightly below
atmospheric pressure (known as negative pressure). This ensures that the airflow
through any leaks in the enclosure will be inwards rather than outwards, so thatasbestos dust is contained within the enclosure. It is necessary to supply sufficient
make-up air to replace the extracted air. This is normally achieved by allowing air
to enter the enclosure in a controlled manner through the airlocks. In this way, theventilation of the enclosure is regulated and a supply of clean air for the asbestos
workers is assured.
6.42 The location of the air extraction unit (also called the NPU) needs to beconsidered to ensure effective airflow management through the enclosure and airlocks.
In principle the NPU should be located opposite the airlocks. The ideal position isshown in Figure 6.13. However the exact location will depend on several factors,
including the layout and shape of the enclosure and the accessibility or suitabilityof walls for siting equipment. Examples of good and poor airflow management are
given in Figures 6.14 and 6.15. The airlock alone may supply sufficient fresh air fora small or simple enclosure, but for larger or complex premises, additional air inlets
may be required. In such circumstances, engineering or ventilation advice should besought. These air inlets should have filtration (pre-filter) in them and be sealed if theenclosure is left overnight with the NPUs turned off. The location of these inlets also
needs to be properly considered to ensure airflow management is not undermined or
short-circuited. To ensure sufficient air distribution within the enclosure, it may also benecessary to duct the exhaust air from further inside the enclosure. This is particularly
important if the airlock and extract unit are to be sited close to one another.
6.43 The NPU should normally be located outside the enclosure with only the
pre-filter visible from the inside. However, this will depend on access and available
space. If flexible ducting is required inside the enclosure between the main HEPA
filter unit and the pre-filter, it may become damaged, allowing the pre-filter to be
bypassed. In such circumstances, this flexible hosing should be protected andregularly inspected.

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Figure 6.13 Ideal NPU position

Threestage
airlock
NPU
Air flow

Enclosure
EnclosureThreestage
baglock

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Figure 6.14 Examples of good airflow management in different shaped buildings

Additional trunking

No access to wall

NPU

Threestage
airlock
Threestage
baglock
Enclosure

No NPU access to wall
Air flow

NPU

Additional trunking
No NPU access to wall
NPU

Threestage
airlockAir flow

Threestage
baglock

Enclosure

Enclosure

NPU

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Figure 6.15 Example of poor airflow management

NPU

Threestage
airlockAir flow

EnclosureThreestage
baglock

NPU

6.44 Extract ventilation should be provided by a purpose-built unit incorporating a
fan and suitable filters. The main characteristics of a good extract ventilation system(see Figure 6.16) are:
n

n

n

n

Adequate filtration. The system needs to incorporate a high-efficiency (HEPA)
filter of at least 99.997% efficiency when tested in accordance with BS 3928:
1969 or the Dioctyl phthalate (DOP) test. The filter needs to be installed on
the negative pressure side of the fan and well sealed around its edges toprevent leakage of contaminated air. The HEPA filter will be the final stage offiltration. Their high efficiency capability means that large quantities of dust
should be avoided. Therefore to prolong its working life, other filter(s) should
be incorporated into the system. A coarse pre-filter should be fitted before the
HEPA filter and it may also be worthwhile fitting a second high efficiency filter.
The machine is then tested as a whole to show that as a unit it has at least
99.997% efficiency.
Adequate fan performance. The fan is required to run for extended periodsof time. It also needs to be capable of achieving its rated airflow against theresistance flow presented by the filters (which will become increasingly dirty andpartially blocked), and any discharge ducting installed and possibly from windpressures if discharging outside. The use of ducting can cause considerable
losses in airflow, typically 0.05-0.07 m3/s (100-150 CFM) per 6-metre length.
Ducting length must therefore be taken into account in calculating the required
ventilation rate. Manufacturers can advise on specific airflow losses linked toducting type and dimensions (length and diameter). In practice this usuallymeans that a centrifugal fan should be used. Fan sizes usually range from
0.084-2.36 m3/s (200-5000 CFM).
Robust construction. The system needs to be designed for continuous
operation and should be constructed of materials of sufficient strength towithstand the wear and tear of normal usage, including frequent transportation
and a degree of rough handling.
Reverse flow damper. A damper or other device needs to be incorporated in
the extract system to prevent reverse flow as a result of fan failure or adverse
wind conditions. Reverse flow would put the enclosure under positive pressure
with respect to atmosphere, resulting in the outward leakage of unfiltered air.

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ventilation unit, showing
typical construction features

Indication of flow. A manometer or similar device should be fitted to NPUs to
indicate that the system is providing an adequate airflow. An audible or visual
warning of low airflow (eg due to filter blockage) is also recommended. Low
airflow is when the airflow drops below the normal or specified output of theunit (which is linked to the minimum air change rate specified for the enclosure,eg 8 air changes per hour (see paragraph 6.47)). The manometer reading
should be checked as part of a visual inspection at the start of each shift (seeBox 6.1).
Discharge ducting. The contaminated air from the extract systems should
be discharged to a safe location in the outside atmosphere. Ducting should
discharge in a safe place away from air intakes, windows, occupied areas, etc,
and preferably away from the sides of buildings or other obstructions whereback pressure could occur in high winds. The dimensions (length and diameter)of the ducting used will be dependent on the location and type of extractor
used, especially the diameter of the exhaust outlet pipe.

Pre-filter

HEPA filter(sandwiched between
pre-filter and fan casing)Control unit withswitches,
warning lights andpressure gauge

Sealingtape

Non-return flap
Connection for
flexible drainage
ducting

Polythene sheeting
forming enclosure

Centrifugal fan(a) General view
Polythene sheeting

Polythene sheeting(b) Method of installation(c) Essential components of extract unit

(Note: Pre-filter should be replaceable from inside
enclosure)(Note: Components may be separated byflexible ducting at A or B in some designs)

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6.45 It is often necessary to replace pre-filters during the course of a job. It
is recommended that stripping operations stop while this is done, to prevent
overloading the HEPA filter. The pre-filters need to be accessible from inside
the enclosure without disturbing the HEPA filter, and when the pre-filter is to be
removed or replaced, the fan needs to be turned off (work should also stop).
Replacement of the final high efficiency filter is more complex and will require
special precautions. The normal practice would be to remove the NPU from theenclosure and install a replacement. Filter replacement would subsequently be
carried out by a specialist contractor under controlled (ie ventilated) conditionsin their premises. There should be strict procedures for the work and it should
be undertaken by competent trained personnel wearing adequate PPE. Afterreplacement of the HEPA filter, the NPU should be DOP tested to ensure theequipment performance is satisfactory, ie that the filter is correctly installed andsealed.
6.46 The level of negative pressure within the enclosure is dependent on
several factors, particularly the extract flow rate and the extent of leakage fromthe unit. Calculation of the ventilation rate must take account of the volume of theenclosure and the volume of the airlock and baglock. It must also include additional
allowances for reduced airflow due to the filters and ducting and due to external
influences (wind pressures). The ventilation rate selected will only be a guide to thenegative pressure within the enclosure as the actual pressure will depend on theextent of leakage into the enclosure. The degree of negative pressure needs to beassessed using a combination of methods including monitoring (see paragraph6.53), visual observation of flow conditions and the use of indicators such as
smoke tubes.
6.47 The exact ventilation requirements for each enclosure will have to be
determined on an individual job basis (based on enclosure size/volumes, building
layout etc). However, while extract system flow rates cannot be specified indetail, experience has shown that in many cases a flow rate of about 0.2 m3/s
for each 100 m3 of enclosed volume (100 ft3/min per 1000 ft3) appear to give asatisfactory performance. This is equivalent to approximately 8 air changes perhour in the enclosure. Where there are difficulties in obtaining an effective seal, it
may be necessary to overextract to compensate. Extraction rates should not be
excessive, causing damage to the integrity of the enclosure (eg collapsing in on
itself). The above rates may not be appropriate for large enclosures. In very large
enclosures, such as power stations, the maintenance of internal negative pressure
may be impracticable. In many cases more effective extraction can be achieved bysubdividing work areas into smaller units (see paragraph 6.19).

Testing, monitoring and maintenance6.48 The responsibility for monitoring and maintenance of the enclosure can beallocated to a nominated, trained and competent person, and there needs to bea system devised which sets out the procedure and frequency of inspection. The
results of the visual inspection, monitoring and maintenance need to be recorded
in a log book. The named person should also be responsible for those duties. It is
recommended that management inspect the log book at frequent intervals. There
are several tests and checks which should be carried out.
Visual inspection
6.49 Before asbestos work starts, a thorough visual inspection of the enclosure
is required to ensure that it has been constructed correctly and that it is effectively
sealed. Particular attention needs to be paid to seals, airlocks, joints, and the fittingof sheeting around pipes, pipe trays, conduits, etc.

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Figure 6.17 An enclosure
being smoke tested

Smoke testing
6.50 The enclosure should be tested by releasing smoke from a smoke generator
inside the enclosure with the air extraction equipment switched off (see Figure
6.17). Escaping smoke indicates leaks which need to be dealt with, as far as
possible.
6.51 Once the enclosure is full of smoke, all external areas should be checked
for the presence of smoke. This should include the floors above and below as
appropriate and any foreseeable locations that smoke could emerge, including lessobvious locations, eg by passing through cavity walls. Major leaks may be apparent
but not always. In certain circumstances, smoke may take some time to emerge,
eg in complex buildings, or where enclosure walls have intricate or multiple folding
and pleating. The visual check should be conducted over a sufficient time period.
Minor leaks will not always be obvious. These minor leaks can still result in thesignificant contamination of adjacent areas. The easiest way to check for smoke
released from minor leaks is to shine a torch beam along the area being checked(see Figure 6.18). Minor releases of smoke will be shown up across the beam oflight. Where the source of the minor leak cannot be traced, reliance may have to beplaced on the enclosure’s air movement (see paragraph 6.47).
6.52 Once the smoke has been cleared and any leaks eliminated, the enclosure
needs to be tested with the air extraction equipment running. The airlock flaps will
be lifted by the airflow through the system and the enclosure walls will bow inwards
indicating slight negative pressure inside the enclosure, ensuring that any residual
leaks are inwards. In any event, air will need to flow through the enclosure purging
the airlocks, establishing circulation within the enclosure and allowing correctfunctioning of the air extraction equipment. Additional leak testing can be performed
externally using smoke tubes, while the air extraction equipment is running, andnoting any smoke sucked inside. Smoke tube testing should be carried out aroundparticular seals and joins to ensure they are effective. Such small amounts of smoke
will not adversely affect the HEPA filter. Only when the integrity of the enclosure andextraction equipment is proven, can asbestos removal work begin.
Differential pressure monitors
6.53 The relative pressure in the enclosure can be monitored using differential
pressure monitors. These instruments provide a continuous indication of the‘negative pressure’ (relative to atmospheric pressure) within the enclosure. A
pressure difference of about 5 pascals or above (0.5 mm water gauge) is usually
sufficient to ensure that there is not net outward movement of air from an enclosure
within a building. However air pressure within the enclosure may not be uniform
and can be subject to external influences. In particular outside wind pressure (iestrong winds) can affect the air pressure within the enclosure through direct impact
on the enclosure side (including floor and ceiling) or through draughts from open
doors and windows in the building. So, considerable care is needed when using
differential pressure monitors, as misleading results can be obtained. Users should
be properly trained. Monitoring results should always be used in conjunction withother indicators of the correct functioning of NPUs, ie satisfactory smoke tests,
tautness of enclosure walls and position of airlock flaps.
6.54 A thorough visual inspection of the enclosure should be carried out at thestart of each working shift to check for any breaches and to establish that theinternal negative pressure is maintained (ie the sides of the enclosure are drawn in).
The NPU pressure gauge should be checked to ensure there is sufficient airflow. It
is also recommended that tests with smoke tubes or differential pressure monitors
be carried out at frequent intervals. Daily checks should be performed where theenclosure is located in an occupied building. The results of the visual inspection,
monitoring and maintenance need to be recorded in a log book.

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Figure 6.18 A torch being
used to find smoke leaks

Viewing panels
6.55 Viewing panels should be checked frequently and cleaned as necessary
to ensure clear views of the inside of the enclosure. Panels can be wiped down as
required. Airborne dust will readily adhere to the perspex surface and will provide
an indicator of the extent of dust generation within the enclosure. If they need to
be cleaned regularly, this suggests limited effectiveness of the controlled stripping
techniques.
Air monitoring
6.56 Air monitoring should be carried out periodically to confirm that theenclosure, airlocks and air extraction equipment are working effectively and noasbestos has spread outside. Monitoring should be performed once work starts
and then periodically to demonstrate continued effectiveness of the system. Air
monitoring in the vicinity of the NPU discharge outlet(s) is necessary where it vents
inside the building. This is particularly important if it has been necessary to replace
the NPU during the operation. Daily monitoring should be performed where theenclosure is located in an occupied building. However monitoring should never beseen as a substitute for frequent thorough visual inspection of the enclosure. The
requirement for monitoring and its extent will depend on the nature of the work andlocation. More attention needs to be given to occupied or sensitive areas and lessto unoccupied or remote locations. Full details on airborne sampling for asbestos
is given in Asbestos: The analysts’ guide for sampling, analysis and clearance
procedures.8
Testing and maintaining air extraction equipment
6.57 Current procedures for the operation and maintenance of air extraction
plant need to be clearly set out, and the users given adequate instruction on how
to operate the system correctly. The system needs to be correctly installed andchecked by a competent person before use; in particular, it is important that theequipment is checked to ensure that it is in good condition and has been properly
assembled. A maintenance schedule needs to be formulated and carefully followed,
and clear instructions given on the action to take if the unit breaks down or fails
to achieve specified performance, eg work should stop and the equipment be
replaced.
6.58 Thorough examination and testing of air extraction equipment must be
carried out at least every six months by a trained and competent person. This
normally involves thorough decontamination and dismantling of the equipment, avisual examination of component parts to establish that they are in efficient working
order and in good repair, and the changing of all filters (unless there is no significant
loss of airflow). The performance of the unit should be checked after it has beenreassembled to establish that airflow through the unit and pressure drop across the
HEPA filter meet the manufacturer’s specification. Where the airflow has dropped
below its design capacity (eg a 2000 CFM unit is only achieving 1500 CFM), thisshould be clearly marked on the unit itself and the lower figure used in ventilation
calculations. Air monitoring in the vicinity of the exhausted air may also prove usefulin establishing that the equipment is functioning correctly in practice following
the thorough examination. However, if it passes the required 99.997% efficiency,
this may not be necessary. A record of inspection, thorough examination, routine
maintenance and any defects remedied must be kept available for inspection.
6.59 The extraction system needs to be turned on before work starts, and beleft running continuously throughout the stripping work, including times when
personnel are not on site. If it is not reasonably practicable to leave the systemrunning continuously outside normal work days, it can be left on during breaks andfor a sufficient period at the end of each shift to clear the enclosure of airborne dust
(at least one hour). On such occasions, access points to the enclosure should beclosed and sealed. Automatic time-delay switches may be used for this purpose.
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The extraction unit needs to be turned on and off from outside the enclosure,and the switches should be clearly identified. When personnel are not on site,
reasonable steps need to be taken to prevent the enclosure being tampered with.
Box 6.1 Enclosure checks■■ Visual inspection and smoke test before work starts.
■■ Visual inspection before each shift, including checking the NPU pressuregauge.
■■ Additional checks with smoke tubes and pressure testing inside the enclosure(daily if the building is occupied).
■■ Air sampling:

Occupied buildings: daily:–– in the vicinity of the enclosure;–– ‘weak spots’ (eg sealed joints);–– airlocks and NPU discharge point(s).
Other situations: soon after work starts and then periodically:–– locations as above.

Dismantling and disposal
6.60 When asbestos removal work has been completed, the enclosure or work
area must be cleaned, inspected and tested in accordance with the requirementsof the four-stage clearance procedures (CAWR, regulation 16). The clearance
procedures will be different where there is no enclosure (see paragraph 6.57).
Guidance on site clearance preparation and four-stage clearance procedures isgiven in paragraphs 7.102-7.146.
6.61 If the clearance air test result is satisfactory, the enclosure should be
carefully dismantled. Following dismantling, stage 4 of the four-stage clearance
procedure can be conducted, ie the site of the work area should be visuallyinspected to ensure that no asbestos waste or debris was hidden by the enclosure
or released during its dismantling. If any contamination is found during thedismantling operations, further cleaning must be carried out and the process ofvisual inspection and air sampling repeated.
6.62 There is still potential for exposure to asbestos fibres during dismantling of
the enclosure. Fibres can be released from the surface of polythene sheets or fromtrapped locations in or under sheeting (eg folds and pleats) or hardboard. Therefore
suitable PPE should be worn and safe systems of work employed. The PPE should
consist of normal coveralls and half-masks (eg disposable FFP3 respirators). All
polythene sheeting should be sprayed with PVA sealant before removal. This will
minimise the release of fibres adhering to the surface through static electricity. The
sheeting should be carefully removed from the framework, rolled or folded neatly
and placed in waste bags. Polythene sheeting should not be reused due to its
potential contamination and loss of integrity due to punctuating by staples. The
sheeting should be disposed of as asbestos waste.
6.63 The NPU should be checked to ensure that it is firmly sealed. It can go
directly to the next job or, if necessary, be taken to a suitable decontamination
workshop for maintenance. Equipment must not be sent to firms, manufacturers,
etc, for maintenance unless they have decontamination facilities or the equipment
has first been thoroughly decontaminated.

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6.64 There may be occasions after the work has been completed and thecertificate of reoccupation has been issued that some additional airborne sampling
will be desirable or appropriate. This ‘reassurance sampling’ is not part of the formal
clearance procedure but would be undertaken in situations where it is possiblethat some residual asbestos may remain and testing is required to ensure that itpresents no risk. These types of situations would include: where suspect asbestos
has been trapped in inaccessible crevices and, although permanent sealing has
been performed, checking is desirable to confirm that it has been effective; or wherecomplex items of plant, electrical equipment, or porous brickwork had been sheetedover inside the enclosure, and checking is required to confirm that no asbestos
penetrated the sheeting. With good planning and careful work practices thesesituations should be avoided. Reassurance sampling is unlikely to be routine and is
not a substitute for any part of the clearance procedure.
6.65 Problems arising from cleaning access equipment used in the enclosure canoften be minimised if sufficient planning has taken place before the equipment istaken into the enclosure. The ends of scaffold tubes should be capped and, where
possible, the scaffold boards covered with polythene to ensure effective cleaning
can be carried out. However boards used inside an enclosure for access to plantat high level may create a slipping hazard if covered with polythene. It may beovercome by using additional boarding, eg plywood. In such cases, the risk needs
to be carefully considered before a decision is made.
6.66 Mobile equipment working platforms (MEWPs) (eg scissor lifts) can be used
inside enclosures, provided that adequate arrangements are made to protect theequipment and for decontamination. Working parts (engine, hydraulic equipmentetc) should be protected using properly designed robust sheeting (fabric material)
which extends and contracts with adjustment of the platform height. Sheetingshould extend as close as possible to floor or ground level and have provision toallow dispersion of exhaust gases (if appropriate) (see Figure 6.19). All exposed
items (ie sheeting, lower parts of the equipment such as wheels and bodywork,and the working platform itself), should be decontaminated and cleaned before
site clearance. MEWPs should be inspected as part of the four-stage clearance
procedure. Sheeting should be treated with PVA before removal and then bedisposed of as asbestos waste.
6.67 Where there is no enclosure, site clearance will follow most of the normal
process, but there will be some important differences. There should be apreliminary check of site condition and job completeness, and a thorough visualinspection. The need for air monitoring will depend on the circumstances of
the work. For example, if the work has been located outside then clearance air
monitoring will not be expected. The final visual inspection will take place after all
equipment and any other items, such as partial enclosures or protective sheeting,have been removed.

Emergency procedures
6.68 The risk of an accident occurring in an enclosure during asbestos removal
is always a possibility, eg from working at heights in difficult or confined areas.
Accordingly, emergency procedures for the evacuation of ill or injured personnel need
to be built into the planning stage and detailed in the written assessment. This is now
required under CAWR, regulation 14. Personnel need to be trained to deal with the
emergency. It may be necessary to remove the victim’s respirator at an early stage.
Decontamination should be carried out as far as possible. Employees should vacuum
themselves, and the victim, and sponge down RPE and boots. However evacuationof the seriously ill or injured employee should not be delayed by over-elaborate
attempts to decontaminate the casualty. If the victim can be moved, work colleagues
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can move them outside. If necessary, entry/exit may be made by slitting the walls of
the enclosure. All personnel should decontaminate themselves in the hygiene facility
again where possible. In some situations it may be necessary for the casualty to betreated inside the enclosure.
6.69 Arrangements for contacting the emergency services should be established.
Information should be made available to the relevant accident and emergency
services to enable those services to prepare their own response proceduresand precautionary measures for asbestos and other hazards. Spare disposable
protective clothing and disposable RPE should be kept available for personnel
who have to enter the enclosure and who do not have their own equipment, eg
ambulance personnel or paramedics.
6.70 As asbestos personnel work in many different premises and buildings, it
is important that they are familiar with procedures and arrangements in the eventof fire. Such matters should be covered as part of the site induction process.
Workers should be informed of the nature of the fire alarms or systems and withthe means of escape from the enclosure and the area in which it is situated. This
will be particularly important if the enclosure (or indeed hygiene facility) is locatedin a relatively inaccessible part of the premises, or if the escape route is awkward
or lengthy. If escape becomes necessary, evacuation from the premises shouldbe the overwhelming priority. Escape should not be delayed by undergoing
decontamination. In addition, RPE should be removed inside the enclosure if it
inhibits or impedes escape. After reaching a safe area, PPE and RPE should be
decontaminated as far as possible.

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Chapter 7: Controlled techniques
for the removal and repair ofACMs, including waste disposal

Summarynnn

Wetting solutions– Water on its own is not adequate to wet asbestos fibres.
Injection– Needles should be sufficient to wet all areas of the ACM.
– Needles should be evenly spaced.
– Needles should penetrate the full depth of the ACM.
– Wetting should be through controlled capillary action and not forced delivery.
– ACMs, when ‘wet’, should be doughy in consistency.
– New equipment should comply with PAS 60.
Spraying– Only wets the outer surface, although increased wetting can be achieved
with several sprays over a number of hours.
– Is not suitable for thick pipe insulation or sprayed coatings.
– Can be used for many types of dust suppression (eg when dry spots arefound, debris etc).
n

Dry stripping with control at source– This technique includes wrap-and-cut, glovebags, shadow vacuuming, direct
removal by vacuum systems and enhanced air management.
– Is used where wet stripping is not possible or to supplement wet stripping
techniques to further enhance control.
nWaste disposal– Any asbestos waste should be packaged, labelled and transferredappropriately.
nFinal clearance– Final cleaance should be performed by a person who is:l competent to do so;l independent of the contractors carrying out the work.
– Final clearance should be carried out in four stages:l Stage 1: Preliminary check of site condition and job completeness;l Stage 2: A thorough visual inspection inside the enclosure/work area;l Stage 3: Clearance air monitoring;l Stage 4: Final assessment post-enclosure/work area dismantling.
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Contents
Introduction

HSE research

113

114

Choosing an asbestos stripping technique

Does the ACM need to be removed? 115

115

Asbestos stripping techniques 116

Basic guidelines 116
Controlled wet stripping 118
Dry stripping with control at source 125

Asbestos stripping situations to avoid
Uncontrolled dry stripping 130
High-pressure water jetting 130
Power tools 130
Hot working 130

130Site cleaning and preparation for four-stage clearance
Disposal of asbestos waste

133

134

What is asbestos waste? 134
How to package and label waste 135
Transfer of waste to sealed skip or vehicle 137
Storage of asbestos waste 138
Transfer for disposal 138
Carriage of dangerous goods requirements 138

Site assessment for reoccupation (Four-stage clearance procedure)

139

Stage 1: Preliminary check of site condition and job completeness 140
Stage 2: A thorough visual inspection inside the enclosure/work area 144
Stage 3: Clearance indicator air sampling for the certificate of reoccupation 148
Stage 4: Final assessment post-enclosure/work area dismantling 150

Appendix 7.1: Labelling requirements for plastic bags/sacks containing asbestos
waste 152
Appendix 7.2: Asbestos waste flow charts 153
Appendix 7.3: Asbestos waste tremcard information 155

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Introduction
7.1
n
n
n

This chapter covers the following topic areas:
general guidance on controlled asbestos removal techniques;
the four-stage clearance procedure;
cleaning and disposal of asbestos waste.

Box 7.1 The publicly available specifications (PASs) for equipment used in workwith ACMs
Equipment used for the controlled removal of ACMs includes controlled stripping
equipment, type ‘H’ vacuum cleaners, NPUs, and DCUs. Whatever equipment isselected for use, it should be of a standard sufficient to ensure compliance with
CAWR. Employers of licensed asbestos removal operatives should ensure thatany equipment they hire or purchase is capable of performing to the standards
required. For example wet stripping equipment can only be deemed to becontrolled stripping equipment, if it is able to thoroughly wet all areas of theasbestos insulation. One way of ensuring that the equipment you hire or purchaseis fit for purpose is to only use equipment that meets PAS 60. Full details on PAS
60 are given below:
PAS 60 ‘Equipment used in the controlled removal of asbestos containing
materials’ has three parts, each constituting an individual specification or code ofpractice:
Part 1 (PAS 60/1): ‘Controlled wetting of asbestos containing materials -Specification’. This specification includes sections on design, instructions for
installation and use, labelling and conformity marking with an annex on flow
measurements from needles. It does not however include information on wetting
fluids and wettability.
Part 2 (PAS 60/2): ‘Negative pressure units - Specification’. This is similar to Part

1 in that it includes sections on design, instructions etc but has two annexes onairflow testing and reporting. It should help address the issue of defining airflow
capacity.
Part 3 (PAS 60/3): ‘Operation, cleaning and maintenance of type ‘H’ vacuum

cleaners - Code of practice’. This document is different. It is a code of practiceon training, operation, cleaning, maintenance and record-keeping for type ‘H’vacuum cleaners. It contains a requirement to have a filtration test certificate
for the entire vacuum cleaner and not just for the HEPA filter. It also has similar
requirements for filtration testing to those in PAS 60/2.
Licensed contractors will be expected to ensure that any new equipment they buy
conforms to the relevant PAS specification. Equipment that conforms to PAS

60/1 and 60/2 will be clearly labelled and should be easy to identify. As far as
manufacturers are concerned, it will be in their interests to ensure that they areable to supply their clients with equipment, which conforms to the relevant
PAS specification. Contractors will be able to comply with PAS 60/3 by putting
in place and implementing a regime, which fulfils the requirements of the code ofpractice for type ‘H’ vacuum cleaners.

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Figure 7.1 Uncontrolled
dry stripping

7.2
This chapter revises and replaces the HSE guidance Controlled asbestos
stripping techniques. It gives practical advice on techniques for the safe removalof ACMs, covered by the Asbestos (Licensing) Regulations 1983 (as amended),1 ie
asbestos insulation, asbestos coating and AIB. It does not cover the following:nnn

the safe removal of ACMs not covered by the Asbestos (Licensing) Regulations
1983 (as amended).1 However, guidance on non-licensed work is given in
Asbestos essentials. There are two publications, An introduction to asbestos
essentials13 and Asbestos essentials task manual,2 both available from HSE
Books. Detailed guidance on working with asbestos cement is given in the HSE
guidance Working with asbestos cement;3
work clearing land contaminated with asbestos. However, some of theprinciples discussed here can be applied to work on contaminated land;safe means of access, demolition, use of ladders and scaffolding etc.
Guidance on safety on construction sites can be found in the HSE construction
information sheets CIS4928 and CIS10,29 and in the HSE guidance Health andsafety in roof work.30

HSE research
7.3
The guidance given in this document takes account of the findings of HSEsponsored research on:
n
n
n

7.4
n

n
n
n
n
n
n
n

exposures experienced during dry stripping of asbestos;
exposures experienced during controlled wet stripping of asbestos;
the workplace effectiveness of RPE.
Several conclusions have emerged from this research, including:uncontrolled dry stripping of asbestos must not take place as it exposes
asbestos stripping workers to very high concentrations of asbestos fibres,levels well in excess of the protection provided by RPE (see Figure 7.1). Notethat ‘uncontrolled dry stripping’ means the removal of asbestos while
in a dry state and using direct action on the asbestos (ie power tools,
axes, hammers etc). It does not include the use of acceptable controlled
techniques, eg unscrewing tiles or boards with shadow vacuuming;
controlled wet stripping techniques can minimise the release of asbestos fibres
and help to contain the spread of contamination;
improved rates of wetting are achieved by the use of wetting agents;a combination of controlled stripping techniques is often needed for effective
control;
controlled stripping techniques require disciplined work practices;
RPE should not be relied upon as the sole way of controlling exposure during
asbestos stripping;
the effective workplace protection provided by RPE has been found to be much
lower than when it is measured in laboratory tests;
the stripping of asbestos from live heating systems and other hot environments
leads to increased fibre levels and reduced performance of RPE, and thepotential for heat stress. It can only be carried out in exceptional, fully justifiable
circumstances, after completion of an adequate RA.

7.5
These findings emphasise the importance of regulation 10 of CAWR. This
regulation requires employers to prevent exposure of their employees to asbestos,or where this is not reasonably practicable to reduce it to the lowest levelreasonably practicable by measures other than using RPE.

Uncontrolled removal of asbestos can result in exposures of1000 f/ml
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Controlled removal of asbestos can result in exposures less than
1 f/ml, and even less than 0.01 f/ml
Choosing an asbestos stripping technique
Does the ACM need to be removed?
7.6
Before making any decisions about how the ACM should be removed
and the control techniques to adopt, first consider whether the ACM needs to be
removed (this has been discussed in more detail in paragraphs 1.42–1.45).
7.7
Where the decision is made to remove ACM, the licensed asbestos removal
contractor needs to consider a number of matters before deciding on the stripping
technique, or combination of techniques, to use (these should be detailed in theassessment and POW). These matters include:n the need to minimise the amount of fibres generated at the point whereasbestos is being stripped. Power tools should be avoided where possible andthe asbestos should not be dry when worked on, with the exception of, eg
electric screwdrivers used to unscrew AIB panels;n the type of ACM, eg:– where there is an impervious cement layer on pipe lagging which will resist
wetting;– where lagging such as blankets is better wetted using sprays rather thaninjection;– where AIB is fixed by different methods (eg screws, nails, clips or glue);n the surface onto which the asbestos has been applied. For example a sprayedcoating may have been applied onto a bituminous layer on structural steel
work. This will make the removal of residual asbestos difficult;n the location of the ACM and the nature of the work area;n the need to prevent the escape of asbestos fibres from the enclosure to thegeneral environment. The use of controlled stripping techniques will minimise
the concentration of asbestos fibres within the enclosure and make theircontainment easier. Further guidance on the design and construction of
enclosures is given in Chapter 6.
7.8
In addition to the requirement to reduce exposure to asbestos as low
as reasonably practicable, the licensed contractor also needs to consider theconditions under which the work will be carried out. Such conditions include where:nnn

the presence of live electrical equipment will prevent, or restrict, the use ofcontrolled wet stripping;
the presence of chemicals may present a direct risk to the workers or preventthe use of controlled wet stripping techniques;
the use of wetting agents may create a risk of slips. This is particularly
important when working at height.

7.9
ACMs should not be removed or repaired in hot environments. This applies
to work on, or adjacent to, hot plant and to circumstances or conditions where theenclosure is likely to reach very high temperatures for other reasons. Enclosures will
get hotter as insulation from live pipework is removed. If, in extreme circumstances,
the asbestos has to be removed or repaired while the plant, or adjacent plant is on,an assessment of the associated risks should be carried out and the methods toreduce the risk of heat stress established (see paragraphs 7.72-7.80).

Do not work on ACMs on or adjacent to hot plant

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7.10 These factors should be considered in co-operation with the client to ensurethat the work is carried out as safely as possible. Liaison with the client or theclient’s agents is necessary to ensure that all the factors, which might influence thesafety of the work, have been taken into account in the assessment and POW.

Asbestos stripping techniques
Figure 7.2 Wrap-and-cut

Basic guidelines
7.11 The primary objective in asbestos removal work is to prevent or minimise
fibre release, ie remove the asbestos in a safe manner. This should always be themain priority. So the choice of stripping method and the work methods need tobe carefully considered to make sure that the most appropriate techniques are
employed. The chosen stripping method (or combination of methods) should
disturb the ACM as little as possible and the ACM should be treated or controlled
to prevent fibre release.
7.12 There are a number of controlled stripping techniques which can be used tominimise the release of fibres during asbestos removal. These can be divided into
the following two broad categories:
Figure 7.3 Injectionnncontrolled wet stripping (paragraphs 7.17-7.41);
dry stripping with control at source (paragraphs 7.42-7.62).

The stripping method should disturb the fibres as little as possible
7.13 The type of method (or combination of methods) used in asbestos stripping
will depend on a number of factors. These factors include:
n
n
n
n
n
Figure 7.4 A low pressure
spray

the type of asbestos product, eg lagging, sprayed coating, board;
the thickness of the ACM;
the presence and nature of any coating on the ACM;
the type and nature of any fixing, eg nailed, screwed;
miscellaneous factors, eg whether pipework is redundant, the material isdamaged, accessibility, etc.

7.14 Paragraphs 7.14-7.16 provide a guide to the types of stripping methods
that can be used for ACMs (the methods are discussed more fully in paragraphs
7.17-7.67):
Basic guidelines: Lagging and sprayed coatings (usually found on boilers,
pipework, structural beams and columns)
n Is the pipework or vessel redundant? If yes, then wrap-and-cut may beappropriate (see Figure 7.2).
n Is the material relatively thick (greater than 1 cm) and covered with a coating
which can be punctured by injection needles, eg encapsulated sprayedcoatings? If yes, then low pressure injection can be used (see Figure 7.3).
n Is the material damaged? If yes, then wrap in polythene and tape up to prevent
loss of fluid. Inject through the polythene.
n Is the material unsealed and relatively thin, for example unpainted sprayedcoatings less than 1 cm thick? If yes, then controlled low pressure sprays canbe used (see Figure 7.4).

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vacuuming during
unscrewing of board

Figure 7.6 Drilling using a
low-speed drill with cowl andfitted with LEV

Figure 7.7 Textured
coating being drilled throughpaste

Is there an impermeable layer which cannot be punctured by injection needles,eg pipe lagging with a hard cement coating? If yes, then injection holes can beprepared by using:– hand drills and shadow vacuuming (this is where the nozzle, fitted with asuitable attachment, of a type H (BS 5415)31 vacuum cleaner is held as close
as possible to the source of fibre release throughout the task (see Figure7.5));– drilling using a low-speed drill with a cowl around the bit and fitted with LEV(see Figure 7.6); or– drilling through a viscous medium such as wallpaper paste or shaving foam(see Figure 7.7).

Basic guidelines: Boards and tiles
n Is one surface unpainted and accessible? If yes, then vacuuming and theuse of controlled low pressure sprays on the unpainted surfaces, followed byshadow vacuuming during unscrewing, are appropriate. Repeated wetting
over approximately 24 hours can wet the board to a soggy cardboard
consistency and reduce the need for shadow vacuuming.
n Is the unpainted surface inaccessible? If yes, then shadow vacuuming while
unscrewing is appropriate, with vacuuming of the exposed and unpainted
surfaces followed by the use of controlled low-pressure sprays.
n Are both surfaces painted? If yes, then shadow vacuuming while unscrewing isappropriate.
n If the boards are nailed, take great care to minimise breakage during removal.
Spraying of unpainted surfaces should be used as described above. To remove
the board, the area of the nail should be strengthened with the use of heavyduty tape and the board carefully eased away from the wall using a crow bar(or similar). Once the nail has been exposed between the board and timber,this can, where possible, be cut. Alternatively, if the boards can’t be easily lifted
without breaking, then scribing and breaking can be used. This should only
be used if other, safer methods will not work as there can be significant fibre
release. Wetting and shadow vacuuming should also be used to minimise fibre
release.
n Magnets can be used to locate screws or nails which have been obscured
due to painting or other coating. If the nails or screws cannot be easily foundor if boards are glued, methods based on the above should be applied. There
will be many and varied situations, however, the principles should be to avoid
breakage as far as reasonably practicable, keep exposed surfaces wet and use
shadow vacuuming when working on the AIB. This may involve paint strippers,
breaking boards etc, but the RA should show that the most appropriate
method has been chosen that reduces exposure as far as is reasonably
practicable.
n Wetting of the AIB surface, particularly the upper surfaces of ceiling tiles, canbe achieved using long (up to 2 metres) metal tubes with holes along theirlength. The metal tubes can be laid on the surface of the AIB and the wetting
agent fed through in a controlled manner.
Basic guidelines: Additional good practice7.15 In addition to the use of controlled stripping techniques, there are otherelements of good working practice which are needed to control exposure.
n

The selection and use of tools and equipment can greatly affect exposurelevels; abrasive power and pneumatic tools in particular can create high fibre
concentrations. Every effort should be made to avoid the use of such tools, ie
power tools should be avoided. Manual tools should be used with shadow
vacuuming where possible. However, where the use of abrasive power andpneumatic tools is unavoidable, they should be used at the lowest effective
speed with additional control measures such as LEV. Examples include a cowl

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n

n

n
n

fitted with extraction located around a drill bit (the cowl should be fitted with aspring so that it remains in contact with the surface of the material as the drill
bit penetrates) or shadow vacuuming.
It is essential that every worker receives adequate training (where identified asa training need, including refresher training), in the use of controlled stripping
techniques, and that there is adequate site supervision. More detailed
training will be required for site supervisors. Good control techniques can bemade worthless by poor work practices, resulting from a lack of training andsupervision. Chapter 4 on training provides guidance for training operatives andsupervisors for work with asbestos insulation and coatings.
The use of controlled stripping techniques does not remove the need for close
supervision and checking that the standards of control and work methods arebeing maintained. Viewing panels provided in enclosures allow supervisors
to check that operators are following instructions and taking the necessary
precautions. If PVC is used for viewing panels, it will attract airborne fibres andtherefore its visible dustiness will be an indication of the effectiveness of thewetting.
Maintenance of control equipment is essential to ensure it continues to operate
effectively.
Good waste control measures need to be used, including clearing away wastematerial as work progresses.

7.16 While some controlled stripping methods (eg multi-point injection) can,in principle, achieve more control than others, the whole range of controlled
techniques may need to be considered for a particular job. A combination or seriesof approaches may be needed for effective control in different aspects or phases of
the work, eg the use of hand or low-powered sprays to dampen asbestos during
the removal of metal cladding from lagging.
Controlled wet stripping
Wetting agents
7.17 Asbestos fibres can be effectively suppressed if the material is properly anduniformly soaked or wetted with a liquid. Some materials can be wetted naturallywith water (eg chrysotile). These are described as hydrophilic. Other materials
such as crocidolite and amosite are hydrophobic and tend to repel water due toa high surface tension. However, the wetting property of water can be improved
through the use of surface acting chemicals (or surfactants, but commonly called
wetting agents or detergents). Wetting agents increase the affinity of water to solidmaterials enabling them to be more readily wetted. Crocidolite and amosite can beeffectively wetted with water containing a wetting agent. In addition, wetting agentsshould also be used with chrysotile products as amphibole asbestos and otherhydrophobic materials may be present (eg calcium silicate), and the wetting agent
will speed up and improve the efficiency of the wetting process.

Water on its own will not adequately wet asbestos fibres
7.18 Wetting agents can be applied by injection or spraying, and are supplied
either ready for use or requiring further dilution. Dilution can be typically between
10:1 and 15:1, according to the manufacturer’s recommendations. Some wetting
agents can ease removal by loosening the binding agents within the ACM.
Principles for controlled wetting
7.19 To achieve effective controlled wetting, several basic rules and principles
need to be understood.

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Wet injection on a large pipennFigure 7.9 Good practice:
Wet injection on pipework

n

n

n

n

n

The objective is to wet the material all the way through. Dry or partially wet
patches will lead to high fibre levels.
The wetting agent should be applied at a rate at which it can be absorbedby the asbestos. Excessive supply rates will lead to loss of wetting agent andincomplete wetting.
Wetting is not an instantaneous process. Sufficient time should be allowed forthe wetting agent to thoroughly penetrate the ACM. The time taken will dependon the type of ACM being injected. More porous and less dense materials,
such as sprayed asbestos coatings, become saturated much more quickly
than denser and less porous materials such as hand applied and high calcium
silicate pipe lagging. It is therefore important that the workers carrying out thewetting and their supervisors have sufficient training and experience to judge
when it is safe to begin removal. Some materials may be removed after only
3-4 hours soaking, while others may require up to 24 hours.
Avoid over-wetting to prevent the wetting agent seeping out of cracks in theasbestos and presenting a slip hazard. It can also cause a slurry which canbe difficult to deal with. Wrapping any damaged pipe lagging (eg with clingfilm) can collect any wetting agent (and asbestos debris), which may seep out.
Alternatively drip trays or troughs can be placed under the pipework, althoughthese can be difficult to position to collect the leaks.
The degree of penetration and wetting should be checked by visual
examination before attempting removal. With some ACMs, there is a visible
colour change when adequate wetting has been achieved. Lagging should beof a dough-like consistency when adequately wetted. The use of dyes in thewetting agent may also assist examination.
Small samples taken to determine the degree of penetration and wetting
should be from areas remote from the pump or towards the last group of
needles. During such testing, ‘shadow’ vacuuming should be used and if any
exposed dry patches are found, they should be sprayed immediately and thenre-injected.
Good wetting:– Complete wetting of the asbestos coating or lagging.
– The asbestos is wet to a doughy consistency.
– Exposure levels are controlled to less than 1 f/ml.
Poor wetting (causes: pressure too high, wrong needles, or needles poorly
positioned):– Areas of the asbestos coating or lagging are completely dry.
– Areas of the asbestos coating or lagging are sodden, with the asbestos
falling off under its own weight.
– Exposure levels are 100 f/ml and higher.

Controlled wetting using injection
7.20 Injection techniques can be used when the outer surface of the ACM issealed, covered or coated and the skin will prevent loss of fluid (eg see Figures
7.8 and 7.9). Injection systems come in two basic forms: multi-point and single
point. Multi-point systems have a number of needles connected together and areconnected to a common injection pump. ‘Hedgehogs’ (where the needles aregrouped together on a flat board) are appropriate for flat surfaces, such as sprayedcoatings on ceilings or beams or lagging on flat plant (see Figure 7.10). Alternatively a‘string of needles’, usually set 10-15 cm apart and linked by tubing from the injection
pump can be wrapped around the item containing asbestos (see Figure 7.11). The
needles in this system can be fitted with individual flow control values which allows
adjustment to ensure the appropriate volume of fluid is delivered to each needle.
The string-of-needle system is extremely flexible and has a much greater range ofapplication than hedgehogs. The latter system is also less practical and requires
repeated placing of the unit on the ACM, increasing the potential for dry spots andwetting time. Single-point injection systems such as needle guns have very limited
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point unit. Single-point injection systems should never be used in place of multi-point
systems.
7.21 Injection needles are available in many sizes and designs. The specificationof the needle will depend on the characteristics of the ACM, particularly thickness,shape and condition.
nnThin coatings or insulation (1 cm or less) require needles with holes at thetip, or long, angled needles. This allows the needle to be pushed into and flatwith the thin coating (see Figure 7.10). These angled needles help the lateral
movement of the wetting agent.
Thick coatings or insulation require long needles with holes along their length,
sufficient to penetrate the full depth of the insulation. The holes should face thesubstrate.

Figure 7.10 Needle board (hedgehog) multi-point injection system and angled needles foruse on thin layers of asbestos, eg a sprayed coating
Structure (concrete - steel - wood)

Asbestos containing material, eg a sprayed coating
Needle board (hedgehog)

Angled needles

Figure 7.11 Controlled multi-point injection delivery through a network of fine needles
Injection needles

Asbestos lagging
Pipe wall

7.22 Once the needles have been selected, consider carefully where to placethem. There are a few simple guidelines to follow:
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injection should be carried out in a methodical manner. If the needles areplaced too far apart, dry patches will occur;
the greater the number of needles, the more likely it is that uniform penetration
will be achieved;
where reasonably practicable, the wetting agent should be applied from the top
so gravity helps it move through the asbestos;horizontal pipes should have needles running along the top of the pipe, spaced
10-15 cm apart (see Figures 7.8 and 7.9), allowing the wetting solution todiffuse down from the top of the lagging;large diameter pipes may need additional runs of needles, again towards the
top of the horizontal pipe;
vertical pipes should have needles placed horizontally around the top of thepipe, allowing wetting solution to diffuse as a wet band down the lagging. They

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ExecutivenFigure 7.12 Wetting
solution diffusing/flooding
from needles

should not spiral down the pipe, but be in horizontal planes;tall vertical pipes may need additional horizontal rings of needles every 1-2
metres.

7.23 Wet injection techniques must be operated at low pressure to ensure that
there is controlled and uniform wetting of the ACM. Wetting takes place throughcapillary action, but gravity will assist downward penetration. The wetting agent
should be delivered at less than 3.4 bar (50 psi) pressure (needles with independent
flow values will allow much better control of fluid delivery). If higher pressure isused, it will force the wetting agent along the paths of least resistance (eg throughcracks and fractures), leading to intermittent wetting.
7.24 Where lagging is covered by a cement-like layer (typically 6 mm thick), it
may prove impossible to carry out injection without some preparatory work. Holescan be carefully drilled in the cement layer to allow access of the needles. Drilling
can be a dusty procedure, so hand drills or a low speed drill should be used. The
use of integral LEV can achieve additional control, eg cowls, by shadow vacuuming
or by drilling through a viscous medium, such as wallpaper paste or shaving foam.
7.25 Pipe and vessel lagging may be covered in metal cladding, which will need
to be carefully removed to expose the lagging material before injection. It may
be possible to carry this out with minimal disturbance to the underlying lagging.
However, if the underlying lagging is likely to be damaged, airless sprays andshadow vacuuming can be used as an effective way of controlling fibre release,
while the cladding is carefully removed. But, if the casing can be drilled, full wetting
should be carried out first.
7.26 Where the asbestos is damaged, injection may result in the material being
disturbed or breaking off. If the damage is relatively slight, this can be avoided by
the liberal use of sprayed wetting agent. If there is the potential for the asbestos tofall off the pipework or vessel, it can be wrapped in an impervious material such as
polythene sheeting or cling film, taped and then carefully injected.
7.27 Take care when there is a suspicion that the insulation is damaged withinternal cracking, or there are materials of varying porosity (eg where repairs havebeen made). These can result in areas of insulation which are difficult to wet as
the fluid takes the line of least resistance. Where cracks are obvious, carefulpositioning of needles can ensure the fluid reaches all areas. Where materials ofvariable porosity are evident, varying flow rates can help. However, such problems
may not be obvious and care should be taken when assessing the wetness of all
the insulation before removal. Where cracking is evident, the insulation should be
wrapped to contain the fluid (tanking), eg where damage is below the injection
height, wrapping will be needed to ensure full wetting.

Remember that poor wetting can be no better than uncontrolled dry
stripping, and very high exposures will result
7.28 Unless the assessment of the work shows that injection can be carried out
without disturbing the ACM (or debris associated with it), the enclosure should becompleted and smoke tested before carrying out any preparatory work or injection.
It is up to the licensed contractor to prove that the method will ensure control,
and they must consider the potential for fibre release from problems such as overwetted asbestos falling and drying out.
7.29 PPE including RPE should be used when injecting. See paragraphs 5.13
and 5.30.

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7.30 Asbestos stripping workers should receive specific and detailed training
in the use of controlled stripping techniques, and in the problems which may be
encountered.
Figure 7.13 Spraying AIB

Box 7.2 Controlled wetting using injection: Key points■■ Ensure needles are correct for the ACM being removed.
■■ Multi-point systems should be used.
■■ Needles should usually be 10-15 cm apart.
■■ Needles should be positioned so that wetting agent can flow by capillary action

to all areas. Dry patches should be avoided.
■■ Low pressure injection (3.4 bar (50 psi)) should be used.
■■ Needles with integral flow control valves aid wetting.
■■ Don’t over-wet, a doughy consistency is about right.
■■ Allow sufficient wetting time.
■■ The equipment will need proper maintenance, testing and checking.

Controlled wetting by spraying
7.31 This technique can be used for applications where injection is inappropriate,
due to the physical nature of the material (eg too hard, unsealed, etc). Spraying
will generally wet the outer surface and penetrate only very thin porous materials.
However, penetration and wetting can be extended by increasing the number ofsprayings and allowing sufficient ‘soak–time’. Spraying can also be used to prepare
surfaces before injection or removal. In summary, spray wetting can be used in thefollowing applications:
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where the ACM is unsealed and porous, eg thin, sprayed coatings;
where the ACM is thin (less than 1 cm thick);
the preparation of ACMs for removal, eg before the injection of damaged pipe
lagging;
the removal of AIB;
asbestos textiles, including blankets and rope seals;
in conjunction with glovebags;
the removal of asbestos debris;
work on asbestos cement. This is dealt with in Working with asbestos cement.3

7.32 The nature of the work being carried out and the volume of asbestos
involved will determine the method of application. For relatively small applications,such as the preparation for injection or removal of AIB tiles (see Figure 7.13),
operators can use hand-pressurised and operated spraying equipment, similar
to that used in gardening. For more extensive applications, such as an unsealed
sprayed coating, a low-pressure spraying machine (less than 3.4 bar (50 psi)) (egairless spray system) or multi-point tubes can apply the wetting agent (see Figures
7.14 and 7.15).
7.33 The objective is to achieve thorough wetting of the ACM without disturbing
it or producing an excessive quantity of run-off.
7.34 The method of application will vary depending on the type of material.
Examples include:nApplication on unsealed sprayed coatings: spraying should be carried out
with care over a defined area, using a wide-angled and fine spray. The sprayshould be moved continuously back and forward across the surface, avoiding
disturbance. The number of spraying passes required will depend on thematerial. Take care during the initial wetting to avoid disturbance of fibres.

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spray system

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n

Application on unpainted AIB boards and tiles: if the boards or tiles areunpainted on both surfaces, or an unpainted surface is readily accessible,
they should be first vacuumed clean to remove all deposits of dust and debris
and then sprayed as described in the previous sub-paragraph. Once they arethoroughly wet, they can be carefully removed by unscrewing and shadow
vacuuming. A magnet can be used to locate the screws or nails if hidden by
paint. Where the unpainted surface is not accessible, as is often the case withceiling tiles, a single tile should be unscrewed using shadow vacuuming, thenthe unpainted top surface vacuumed and sprayed. Once access is available tothe upper surfaces of the surrounding boards or tiles, they can be vacuumed
clean and sprayed before removal, as outlined previously.
Application during preparatory work for injection: as previously outlined,
spraying can be used where the asbestos is slightly damaged and injection
may result in the material being disturbed. Fibre release can be minimised by
the careful, but liberal use of sprayed wetting agent on the damaged areas
during injection.
Application on insulating blankets, ropes, quilt, etc: wetting agents sprayedover all accessible surfaces can be effective in minimising fibre release during
removal (injection is not appropriate for this type of material).
Application on hard surfaces (for example, Keens cement and bulldog
coatings): these coatings may be too hard to inject, and impermeable to thespray application of wetting agents. One method of removal is by drilling undercontrolled conditions followed by injection (see paragraph 7.24). Alternatively,
this type of material can be removed by careful cracking while applying afine spray. Once cracks appear, the spray can be directed along them toaid wetting. The material should then be carefully removed without further
breakage. Shadow vacuuming can also be used in some circumstances.
Because this type of material will not readily soak up the wetting agent, there
is likely to be some spilling of the agent. Polythene sheeting or a suitablecontainer should be placed beneath the spraying point to collect any spillage.
Application during the use of glovebags: glovebags can be used to remove
sections of pipe lagging. Although the asbestos is contained within the
glovebag, the use of sprayed wetting agent during stripping can achieve
additional control. The lance of a garden-type spray can be inserted through apurpose-designed access point and any gaps sealed. It is important to avoid
over-using a wetting agent as this may put an added strain on the glovebag.
Glovebags are discussed in more detail in paragraphs 7.50-7.55.

7.35 The time required for adequate soaking depends on the type of ACM andthe purpose behind the application of the wetting agent. For example if it is being
used to suppress fibre release during preparation for injection, only a few minutes
may be necessary. Dense material may need to be left to soak overnight. Careshould be taken to avoid over-wetting as this can result in some materials, such as
AIB ceiling tiles, collapsing.
Wet stripping in large industrial premises
7.36 Substantial amounts of asbestos lagging can be encountered in older,larger, heavier industrial premises and power stations. For example lagging in the
boiler houses can be 1 m or more thick. These types of situations present certain
challenges in obtaining effective control.
nnnThe boiler houses may be large and complex with many passing pipes.
Consequently, it may be difficult to obtain good enclosure. The size andcomplexity often means that a complete seal cannot be obtained and thatnegative pressure will not be achieved.
The quantity and thickness of the asbestos lagging can make effective wetting
difficult.
Large quantities of asbestos waste and slurry may need to be handled.

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Figure 7.15 Spraying thincoating

Whichever approach is taken, every effort should be made to ensurethat the lagging is as uniformly wetted as possible before stripping.
The size of the job should not be used as a reason for reducing
the level of control
7.37 Where the building is redundant and ready for demolition, the relatively few
people present in adjacent areas makes the job slightly easier. The building can besealed off (in sections if appropriate) and local smoke testing carried out. This thenallows the use of controlled wet stripping techniques, which can be sufficient tocontrol exposure and the spread of asbestos fibres. Leak air sampling can be used
to confirm that control is adequate.
7.38 Where there are people working in adjacent areas or it is difficult to achieve
an adequate seal, additional precautions may be necessary. Smaller enclosures,within the main enclosure, can be built around the items to be stripped, and thenput under negative pressure to provide an additional barrier to the main enclosure.
7.39 Whichever approach is taken, every effort should be made to ensure thatthe lagging is as uniformly wetted as possible before stripping. The size of the job
should not be used as a reason for reducing the level of control. The large quantityof asbestos which needs to be removed can result in very high exposures, if
controlled stripping techniques are not employed. The following technique can be
used:
n

n

The thickness of the material will often prevent wetting being achieved in one
attempt. Wetting should be undertaken progressively. After any preparation
work (eg removing any metal cladding), the lagging can be injected using thelongest needles available, or liberally sprayed with a wetting agent, and allowed
to soak. Wetting agent will only permeate the outer layer of the lagging. Oncethe outer material is wetted, it should be carefully removed until a reduction in
the degree of wetting is noticed. The underlying lagging can then be injected orsprayed again, and the process repeated. Over time even the thickest lagging
can be wetted in this way.
The progressive removal of thick lagging will require more planning andorganisation. Different areas should be able to be worked on simultaneously.
One group of workers can wet an area of lagging, and a second group cansubsequently strip the material while the first group prepares a new area. Thissystem should maximise the speed of the work.

Close supervision is required to ensure the correct use of controlled
stripping techniques
Some problems associated with wet stripping techniques
7.40 Wet stripping is not appropriate in some circumstances, because its use
may introduce additional hazards, eg:nnin the presence of live electrical equipment that cannot be isolated or effectively
sealed from water, although dielectric fluids can be used;
where there is an unavoidable risk of contact between water and chemicals
which may generate toxic or fire risks.

7.41 There are also situations where the use of wetting agents can cause
problems, but these should not prevent the use of wet stripping techniques, eg:nwhere wet work would lead to the discolouration of the fabric of the building,particularly where dyes are added to the wetting agent. The use of polythene
sheeting on susceptible surfaces can prevent this;Asbestos: The licensed contractor’s guide

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ExecutivenFigure 7.16 Wrap-and-cutnnwhere wetting agents may cause skin problems. The manufacturer’s or
supplier’s material safety data sheet should be consulted on the precautions totake;where a slip hazard may be introduced by spillage of the wetting solution.
This can be reduced by placing drip trays or troughs under the area being
treated, but these can be difficult to position to adequately collect the leaks.
Alternatively, non-slip flooring could be used (and disposed of as asbestos
waste). Any spills should be removed;
if there are freezing weather conditions. Wetting agents can be treated to allow
for this. Liquids are also available that work at up to 240oC, although hot work
should be avoided.

Dry stripping with control at source
7.42 There may be some situations where it is not possible to use wet stripping
techniques. In these circumstances, other methods should be used to control
asbestos at source. Indeed, alternative techniques may be preferable in somecases. It is also worth noting that ventilated enclosures do not provide control atsource. They do not regulate fibre release at the point of removal. Their primary
purpose is to reduce the spread of asbestos.
Wrap-and-cut
7.43 In some circumstances it may be more appropriate to use the wrap-andcut method (see Figure 7.16) rather than controlled wet stripping, eg the removalof redundant pipework and vessels. Wrap-and-cut is effective, as it eliminates theneed for wholesale disturbance of the lagging. Consequently, the potential for fibre
generation is much reduced. Wrap-and-cut is particularly suitable for pipework ofsmall diameter (150 mm or less). If the lagging is damaged, wrapping and cutting
can disturb and release fibres. Additional precautions will therefore be required (seeparagraph 7.47). The RA should also consider manual handling risks during theremoval of pipework/vessels.
7.44 This technique requires the lagged pipework or vessels to be securely
wrapped in polythene sheeting before being cut out and disposed of as asbestos
waste. The need for additional precautions such as enclosures, NPUs etc, should
be determined in the assessment of work. Wrap-and-cut does not completely
eliminate asbestos disturbance or release and, in many cases, fibre release will
occur, eg in preparation work, where small sections of lagging have to be removed
to allow cutting of the exposed pipework, or from disturbance of damaged areasof lagging. In general terms, enclosures are required when the wrap-and-cut
work is inside buildings, but may not be necessary when the work is external
and remote. Therefore, full consideration needs to be given on where wrap-andcut can be used and on the need for an enclosure. Due to the potential for fibre
release, enclosures will be likely in most cases. Chapter 6 provides further guidanceon enclosure design and construction.
7.45 Wrap-and-cut is only suitable for lagged pipework or plant in certain
circumstances:nnnn

the items are redundant or are to be replaced;
the items are manageable in size;
the contents of the items have been removed;
the items have been cleaned, where necessary, to remove residual hazardous
materials.

7.46 It is important to only use this technique on manageable items. The handlingof large or awkwardly shaped items of plant can result in injury or the ripping of
the polythene sheeting. Also, it is worth noting that certain disposal sites may notaccept wrapped items with large voids in them, eg a large calorifier.
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7.47 The lagging should generally be in sound condition. If it is damaged,
wrapping and cutting can disturb and release fibres. Additional precautions will
therefore be required. The following methods, in isolation or combination, should be
used to minimise fibre release.
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The lagging can be carefully treated with a penetrating encapsulant which willbind the fibres together. If the lagging is badly damaged, the possibility of fibre
release during application will also need to be considered.
The lagging can be wetted using injection or spraying with a wetting agent.
Small areas of damage, adjacent to the area to be wrapped and cut, can besealed with polythene sheeting and tape, and then worked on using localised
spraying or shadow vacuuming.
Where there are several areas of damage along a length of pipework, the entire
run can be dampened using sprays and wrapped in polythene sheeting.
Wrapped items too large to pass through the baglock should remain in thework area until the four-stage clearance has been completed and the enclosure
removed. The items will be subject to the four-stage clearance process.

7.48 The pipework or plant should be divided off into manageable sections. For
example pipework should be examined for suitable breaks in the lagging where
flanges could be unbolted or pipe hangers removed, or the bare pipe cut, but
without disturbing the asbestos. Where such breaks do not occur naturally, or
if they are not at convenient positions, short sections of lagging will have to be
removed. The size of the sections will also need to take account of the baglock
exit arrangements and the dimensions of the skip. Removal of the asbestos will
require control at source. The wet injection technique can be used (see paragraphs
7.20-7.30). Glovebag systems can also be useful for stripping short sections ofpipework. Details are given in paragraphs 7.50-7.55. Take care to ensure sufficientlagging is removed to allow cutting/burning to take place, without disturbing theremaining asbestos. Once the pipe is ready for dividing or cutting, the lagging
should be wrapped with heavy-duty polythene and the ends of the sections
securely taped or otherwise sealed. The items should be labelled.
7.49 Pipework can be cut using a number of methods. Hacksaws can beused for very small diameter pipes. Abrasive cut-off wheels and flame-cutting
techniques can be used on larger diameter pipework. In such situations, take careto avoid damaging the wrapped ends of the lagging. At least 20-30 cm of exposed
pipework is required to reduce this risk. Where grinding wheels or flame cutting
are used, the pipework should be wrapped in flame-retardant polythene sheeting(care should be taken when using oxyacetylene or oxypropane cutters, as thissheeting is not resistant to these). Vibration from the use of tools may also loosenasbestos on the remaining pipework. The wrapped sections of pipework should
be carefully supported during cutting and/or unbolting, eg by sheet metal bands atsling attachment points. The pipework sections should be transferred to the skip assoon as reasonably practicable. Full PPE (including RPE) must be worn while thismethod of work is in use.
Glovebags
7.50 There are a number of proprietary glovebags, made of strong clear plastic
materials, that are designed to allow stripping activities inside the bag by external
operators using integral plastic gloves. The top part of a glovebag fits around theitem to be stripped while the bottom part acts as storage for tools and asbestos
waste. There are also versions available for removing ceiling tiles and sectionsof sprayed asbestos coating. Figures 7.17–7.18 show glovebags being used
to remove a sprayed coating inside a traditional enclosure. It is important tonote, however, that glovebags have certain drawbacks which prevent them fromsubstituting for enclosures in many applications. The main concern is that there isAsbestos: The licensed contractor’s guide

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Figure 7.17 A sprayedasbestos coating being
removed using a specialised
glovebag within a traditional
enclosure (the dark area
is where the asbestos has
been removed)

no way to prevent asbestos spreading if there is a bag failure, eg through punctures
or from a seal failure.
7.51 Commercially available glovebags vary in strength of material (resistanceto tears and punctures) and in design detail. Where reasonably practicable, thefollowing design features should be considered when purchasing glovebags, toensure that they can be used safely:
n
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n

they should be made from a material which does not tear;
they should have shoulders of sufficient dimension to allow the glovebag to beeffectively sealed to the pipe or vessel;they should have internal zips to allow the waste to be isolated at the bottom.
This allows the top of the bag to be purged on completion of the work,
minimising the release of fibres when the bag is removed;
they should have an entry port for inserting a spray nozzle to wet the asbestos
or a vacuum cleaner nozzle to create negative pressure and so purge the topof the bag on completion of the work.

Manufacturers should be consulted about the range and specification of bags
which are available. They should help select the most appropriate design for theplanned work and provide information on how to use them safely.
Figure 7.18 A glovebag
designed for the removal ofsprayed asbestos coatings.
Note the gloveports, waste
chute and vacuum nozzle
used for cleaning andproviding slight negative
pressure

7.52 Enclosures will usually be needed even when glovebags are being used.
Glovebags can only be used without an enclosure where the assessment shows
minimal risks to other people if the glovebag leaks or fails. This may be the casewhere the site is remote from other workers, eg runs of open-air pipework in achemical works where the prevailing weather conditions could make building andmaintaining an enclosure impractical. However, you should note that there is still
the potential for relatively low concentrations of fibre to leak out from the glovebag
during use, especially through small holes. Consequently, the work area still needs
to be segregated. Glovebags should not be used in occupied areas without
additional precautions, such as enclosures and NPUs.
7.53 Where it is planned to use glovebags, the assessment carried out underregulation 6 of CAWR needs to address the following requirements:
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specific training is needed in the use of glovebags;
the work area is well-defined; moveable items such as furniture are removed;
ledges and other surfaces are covered in polythene sheeting;the glovebag should completely cover the section of pipe or other structure
being worked on;
asbestos debris on nearby surfaces can be dealt with safely;
the glovebag is smoke-tested, eg by the use of a smoke tube;
the operators wear suitable PPE, as determined by the assessment;
where reasonably practicable, the work is carried out with the glovebag underslight negative pressure;
wet stripping techniques, using wetting agents, are applied when reasonably
practicable;
the glovebag is only used once and not reused;
the glovebag is not moved, ie slid along pipes;
the glovebag is not used for jobs requiring more than two glovebags, unlessthe assessment shows that this is safe for the job in hand;
the glovebag needs two operators to use it safely;
contingency plans, and equipment for spillages and clean-up, are in place.

Where the assessment shows that these requirements cannot be met, the use ofglovebags is not appropriate.

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7.54 A variety of tools can be used inside the glovebag. A safe system of
removing the tools from the glovebag, without compromising the glovebag’s
integrity, should be drawn up. For example, the tools can be held in one handwithin the glove of the glovebag, which is then pulled out. The glove can thenbe twisted to enclose the tools in a pouch. The twisted point can then be sealed
at two points several centimetres apart. A cut can then be made between thetwo points, leaving the tools in the glove and the elbow or shoulder of the glove
sealed to prevent any escape of fibres. The glove pouch can be placed in the next
glovebag for use or in a container of water for cleaning.
7.55 There is wider scope for such bags as a supplementary measure inside
enclosures. Where, in exceptional circumstances, controlled wet stripping cannot
be used, the spread of dust can be largely eliminated by carrying out all the primary
removal using glovebags within the enclosure. They may also have a role in final
cleaning, where there are residues which prove hard to remove. The glovebag
versions for overhead removal of ceiling tiles and sprayed asbestos coatings arealso likely to be useful.
Direct removal by vacuum systems
7.56 Direct vacuum removal uses a combination of removing and vacuuming
away asbestos material at source, by purpose-designed vacuum equipment.
However, this method does not remove the need for an enclosure and otherprecautions. It is one method of removing loose asbestos which has been ‘blown indry’ as thermal or noise insulation, and where wetting could cause the asbestos tobond to the underlying surface.
7.57 Waste asbestos is drawn from the stripping position to a remotecollection unit by means of a vacuum transfer duct. This has the advantage thatit considerably reduces the manual handling of waste, thereby saving time andexpense, especially on large-scale jobs. Also, if adequate precautions are taken,
the overall exposure is reduced.
7.58 Where this type of system is adopted, the assessment and POW should
clearly identify the precautions to use and the procedures to follow in the event ofproblems such as blocked ducting, etc.
7.59 By its nature, this technique cannot be carried out with the asbestos wet.
However, it can provide an equivalent level of control to that provided by controlled
wet stripping, if the equipment is well-maintained and operated. Any residualmaterial that remains after vacuuming can be wetted with a sprayed wetting agent,and then removed.
7.60 The technique has the disadvantage that a rapidly moving stream of dry
asbestos material has to be transported, the asbestos material isolated andbagged. If the bagging unit is remote from the removal enclosure, it should behoused in a separate ventilated enclosure at negative pressure to prevent leaks,
and treated as part of the stripping operation. Exhaust air should be filtered to ahigh standard before discharge (ie HEPA filtration). Since the waste material fromthe filters is also dry, rigorous precautions are required during disposal.
7.61 Because the bagging unit is handling quantities of dry loose asbestos
moving at speed, there is the potential for high exposures if a leak occurs.
Consequently, the assessment of the work under regulation 6 of CAWR should
also address work in the enclosure containing the bagging unit. This enclosurenormally needs to be constructed to the same standard as the stripping enclosure;it should be smoke-tested and have negative pressure applied. The numberof workers in the enclosure, and the time spent in there, should be kept to aminimum. They should be issued with suitable PPE and RPE, as determined by theAsbestos: The licensed contractor’s guide

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as issued to the workers in the stripping enclosure. They should also follow thesame decontamination procedures. Once the work is complete and the enclosure
cleaned, it will be included in the four-stage clearance procedure (see paragraphs
7.102–7.145).
7.62 If the transfer ducting becomes blocked, it should be securely capped atboth ends and drawn into the stripping enclosure, where it can be opened andcleared. Consideration and care are required when capping the end next to thevacuum equipment. It is important that where the ducting passes through the wallof the enclosure, any opening is immediately sealed. Where this is the case, work
should be stopped and sufficient time allowed for the enclosure to be purged
before drawing the ducting in.
Enhanced air management
7.63 Enhanced air management can be used for any type of stripping work. It isparticularly helpful when controlled wetting or other controlled stripping techniques
cannot be used. Because stripping may be carried out dry, with the potential forhigh exposures, it is very important to carefully plan and closely monitor the job.
Only companies and individuals who have had specific training should use thetechnique.
7.64 With the technique, air is introduced by a blower unit close to the area ofwork and then the air is extracted at a higher rate to maintain negative pressure.
The blower should be fitted with a manometer to detect changes in the negative
pressure. If the negative pressure falls below a pre-determined level, the blower
should automatically shut off and an in-built valve close, so that the pressure in theenclosure, relative to outside, cannot become positive.
7.65 To effectively reduce the exposure in the stripping area, the blower andnegative pressure outlet points should be located close to the active work area
and opposite each other, to draw the contaminated air away from the front of
the worker. Push-pull of air independent of the enclosure negative pressure will
improve control. However, the blower should not be located so close that it
actively disperses the asbestos fibres, so making capture by the exhaust difficult.
If the blower and negative pressure inlet points are too far from the active work
area or located incorrectly, control of exposure will not be achieved. As thework progresses, the blower and negative pressure inlet points will need to berepositioned to ensure optimum efficiency. The workers should always try to belocated to the side of the blower unit.
7.66 Because this is a complex system to operate and requires constantmonitoring, it is mainly applicable when there are problems using other controlled
stripping techniques. Where possible, the controlled stripping techniques previously
described should be the first choice. Adopting enhanced air management does not
exclude the use of other controlled stripping techniques.
7.67 Where other controlled techniques are used but the assessment indicatesthat high exposures may still occur, enhanced air management can be one way ofproviding additional control.

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Asbestos stripping situations to avoid
Uncontrolled dry stripping
7.68 The term ‘uncontrolled dry stripping’ is applied to stripping ACM in its dry
state within an enclosure, but without any direct controls to reduce exposure.
Airborne asbestos fibre concentrations in these situations will be excessively high(up to 100-1000 f/ml for sprayed coatings) and will result in significant asbestos
exposure even when strippers are wearing their normal high performance RPE.
The RPE is unable to provide adequate protection for these fibre levels. In addition
worker exposure will not be reduced to any extent through the air extraction in
the enclosure. Uncontrolled dry stripping is unacceptable and unnecessary.
It must never take place. Some form of control is always available whether
it is direct control at source (eg wet stripping or shadow vacuuming) or otherspecialised techniques, such as glovebags or enhanced air management.
High-pressure water jetting
7.69 High-pressure water jetting has been used to remove asbestos fromconcrete floors, beams, and columns. It is a highly specialised technique whichremoves ACMs using water jets normally operating at pressures of about 138 bar(2000 psi) or above. This technique has a number of disadvantages, including:
n
n

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n

asbestos fibres are physically unable to absorb the water;a vast amount of virtually unmanageable slurry containing free asbestos fibres
is produced; the slurry can be difficult to contain which leads to the spread ofasbestos;
the jet can cause serious injury;
a mist of fine water droplets is formed which will wet the filters in RPE. This
may affect the protection provided by the RPE, eg through increased breathing
resistance or decreased airflow.

7.70 High-pressure water jetting is not controlled wet stripping, and it should only
be used in exceptional circumstances and with specialist advice.
Power tools
7.71 Power tools have the potential to generate extremely high levels of asbestos
fibres. There are numerous types of tools including drills, chisels, screwdrivers,
sanders and disc cutters/angle-grinders. Where possible, their use on ACMs should
be avoided and preference given to manual equipment, as it generally producesmuch lower dust levels. However, it is recognised that it may be necessary to use
power tools in some circumstances. In these situations, the emphasis should still
be on minimising fibre release. The tools should be used at their lowest possible
setting and in conjunction with other control measures, such as shadow vacuuming
and dust suppression materials (eg foams and pastes). In addition there may beoccasions where more aggressive removal techniques are required, eg to remove
residual minor amounts of textured coatings. Dust suppression (eg airless sprays)
should be employed. Disc cutters and sanders should not be used to cut throughor remove ACMs.
Hot working
7.72 The most likely source of heat will be from hot plant (eg boilers, calorifiers,
pipework etc) either being worked on directly or located nearby. However, hotenvironments may arise from other sources, particularly due to weather conditions.
High air temperatures and/or situations where there is direct sunlight (eg exposed
enclosures) can cause elevated thermal conditions.
7.73 Working in hot conditions can cause a number of ill health effects ranging
in severity, but including acute and potentially fatal conditions such as heat stroke.
The range of effects is summarised in Box 7.3.
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7.74 Hot working and asbestos removal are almost incompatible activities. There
are fundamental issues which make asbestos and hot working extremely difficult
to manage and control. In particular, the various precautions needed to protect
workers from exposure to asbestos dust and to prevent its spread can result ina greatly increased thermal health risk. For example: PPE, RPE and enclosures
all serve to prevent and restrict heat dissipation, and the PPE and RPE increases
sweating and inhibits body cooling. Also, the implementation of a successfulheat stress control regime (eg work/rest breaks, access to drinks etc) is impeded
in asbestos enclosures, due to the complex entry and exit/decontamination
procedures.
7.75 In addition to the heat stress issues, hot work can also lead to deteriorationin asbestos control. For example: wetting of ACMs, particularly insulation on hot
pipes, is more difficult to obtain; the integrity of the enclosure can be difficult
to maintain as high temperatures and radiant heat soften polythene sheeting
and weaken joints and seams; and in the event of a failure in the enclosure,strong convective currents can escape causing significant contamination of thesurrounding area.
7.76 Therefore, hot work with asbestos is to be avoided where possible. All
avenues should be explored to remove the heat source. Wherever possible hot
plant should be shut down or turned off and allowed to cool before asbestos
removal work begins. In many cases contractors and their clients have found that
this is the quickest and most cost-effective way of dealing with the potential heatstress problems which can arise when asbestos removal work is attempted on hot
plant.
7.77 Hot work will only be permittable in exceptional and fully justifiable
circumstances and, as it must be notified on the FOD ASB5 form (see Appendix
3.1), it is likely to be challenged during notification. Work will only be allowed afteran adequate RA has been performed (see paragraph 7.78) and where the thermalrisks have been minimised in a well-planned and properly designed control regime(see paragraph 7.80). Where hot work is being considered, contractors may needto take specialised advice from an occupational hygienist or other consultant.
Contractors may also wish to discuss the matter with the enforcing authority before
proceeding.
7.78 The RA will need to be thorough and comprehensive. It will need to cover all
the factors which affect heat stress. These include:nnn

working environment and conditions: air temperature, radiant heat, humidity,
air movement, number/extent/location of heat sources, size/shape of premises
etc;
work rate: physical nature of the job;
worker/personal factors: age, fitness, health status etc.

7.79 Every effort should be made to prevent the need for hot working. Workshould be scheduled to be done during plant shutdown or annual holiday or in
the evening or overnight when hot conditions are due to the climate. Where work
arises at short notice through incidents or emergencies, then short-term remedialaction should be taken as far as possible (eg by making temporary repairs or
encapsulation) until the work can be incorporated into a programmed plant shutdown and carried out with the plant cold.
7.80 Where hot work is unavoidable then the thermal risks should be minimised
through a well-planned and properly designed regime which should be based on
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n

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n

minimising heat sources: stopping all boilers and other process plant orequipment operating as far as possible and operating others at minimum
temperatures, eg where there are two boilers, switch one off and operate theother at the lowest setting and then reverse the arrangement;
minimising heat spread: through the use of temporary insulation (sacrificial
lagging) to cover hot surfaces as they are stripped of existing insulation andthrough shielding radiant surfaces with low emissivity material or erection ofradiant heat barriers;
effective air management in the enclosure: employment of higher ventilation
rates; removal of air at high level; location of the supply and extract vents toensure a positive rate of air change at the working position;
positive cooling in the enclosure: by drawing make-up from outside the heataffected area or by the use of an air conditioning unit;
localised cooling: the use of free-standing fans within the enclosure to provide
local air movement at the working position (Note: care must be taken to avoid
excessive air currents in the enclosure as they could cause disturbance of dust
and could adversely affect the integrity of the enclosure);
regulating the length of exposure through job rotation: it may be possible
to rotate workers so that individual time spent in the hot area is minimised;
implementing periodic rest breaks and rest facilities in cooler conditions (thework/rest ratio would depend on the conditions);
preventing dehydration: providing cool water in the rest facility and encouraging
workers to drink it in small amounts before work, during breaks and after work;
providing training: covering the risks of heat stress associated with the work,
symptoms to look out for, safe working practices and emergency procedures;providing adequate supervision: particular attention should be paid to ensurethat the control regime is implemented and that it continues to operatesatisfactorily for the duration of the work. Work/rest regimes should be strictly
enforced;monitoring the thermal conditions and the health of workers: advice should besought from occupational health professionals on a health monitoring regime.

Box 7.3: Health effects from working at high temperatures■■ Burns: caused by contact with hot surfaces or by radiant heat.
■■ Superficial effects: swelling of feet and ankles, heat rash.
■■ Fainting: due to a reduction in blood pressure to the brain. This can be serious

if the person is held upright or injured in a fall.
■■ Muscle cramps, nausea, vomiting: due to salt depletion caused by excessive

sweating.
■■ Heat exhaustion: caused by dehydration due to excessive loss of sweat.

Symptoms include: fatigue, giddiness, nausea, headache, breathing difficulties,
extreme thirst, muscle cramps.
■■ Heat stroke: an acute and potentially fatal condition caused by a rise in bodycore temperature above 40oC. The condition may occur suddenly with nowarning or may be preceded by headache, dizziness, confusion, faintness,
restlessness or vomiting.

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Site cleaning and preparation for four-stage clearance
Figure 7.19 A Type H
vacuum cleaner

7.81 Regulation 16 of CAWR places a duty to ensure that the work areas andwork equipment are kept in a clean state and are thoroughly cleaned. Employers
should therefore use work methods and equipment which prevent or minimise
the build-up of asbestos debris and waste on floors and surfaces in the workarea. Where possible, the ACM should be placed directly into waste bags as itis removed. This is the most efficient arrangement and eliminates extra handling.
In other situations employers must make sure that any asbestos dust and debris
is cleaned up and removed regularly to prevent it accumulating and drying out
where wet removal techniques have been used. There should be frequent cleaning
throughout the work period and a clean at the end of each shift. Controlled wetting(eg using airless or light sprays) should be used to keep residues damp, particularly
before bagging.
7.82 Cleaning methods should not create dust. Brushes or brooms should not
be used for cleaning. Dust and debris should be dampened down as necessary
before cleaning. Waste should be cleaned up using a combination of methods.
Waste should be vacuumed up as far as possible. Type H vacuum cleaners which
are designed to the British Standard (BS 5415)31 (the vacuuming specification
for hazardous dusts) are the type which should be used with asbestos (but noteparagraph 7.83). This equipment is fitted with a HEPA filter and is designed fordust-free disposal. Type H vacuum cleaners come with a range of attachments(brushes, narrow and broad slots) which allow their use on many types of surfaces
and materials. Domestic or general purpose vacuum cleaners do not meet therequired specification and should not be used. Pieces of debris can be cleaned up
using rakes and shovels. Damp clothes and wipes should be used for additional
cleaning of surfaces.
7.83 The type H vacuum cleaner should not be used on very wet material.
Excessive liquid will damage the HEPA filter. Such material should be collectedusing rakes and shovels. However there may be occasions where there is asignificant spillage of liquid or water. In these situations vacuum cleaners suitablefor wet use can be employed, but only in a strictly controlled matter. The vacuum
cleaner will need immediate cleaning and decontamination after use. In addition,
arrangements should be made for safe removal and disposal of the filter.
7.84 Once the removal of the asbestos has been completed and all the waste
and other non-essential items (tools, equipment, materials, etc) have been
removed, the enclosure (ie work area) including airlocks and baglocks, is ready forthe final clean and preparation for the four-stage clearance procedure. At this point,
the pre-filters on the air extraction equipment should be replaced with new filters.
The whole work area including all surfaces and items should be thoroughly cleaned
using dustless methods. Fine dust will have settled or become attached to every
possible surface in the work area. This includes floors, walls, all sides of sheeted
items, high-level surfaces, pipes, ductwork, cables, undersides of items (pipes,
ledges), behind and below plant, equipment and other furnishings and fittings (thislist is not exhaustive). Every surface should be cleaned. Complete cleaning will be
more easily achieved if it is carried out in a methodical and systematic manner. The
type H vacuum cleaner should be used for the initial clean, with appropriate use
made of the different attachments. The brush head attachment is particularly usefulfor uneven and rounded surfaces. Surfaces should then be wiped as necessary
with damp cloths or wipes to ensure all fine settled dust has been removed.
7.85 At this point sheeting or boarding which has been used to protect any
equipment, plant or other items or to protect surfaces, including sacrificial flooring,should be removed. It is acceptable, indeed sensible, to spray this sheeting withan adhesive sealant, eg PVA, before removal to reduce the potential for release
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Executiveof residual fine settled dust. However, the use of the spray must be strictly limited
to this sheeting and extreme care should be taken to prevent the spread ofsealant onto other surfaces which would inhibit the issuing of the certificate ofreoccupation. After removal of the protective sheeting, the underlying surfaces
should be checked for any dust or debris which may have penetrated or settled on
to them. The surfaces should be cleaned as appropriate.
7.86 Finally the contractor should carry out a thorough visual inspection to ensurethat there has been complete removal of the ACM as planned and that the work
area has been properly cleaned of visible debris and fine settled dust. All nonessential items should be removed from the work area. The only remaining items
should be any wrapped waste that could not be removed through the baglock
system, a type H vacuum cleaner and wipes and waste bags which may benecessary for additional cleaning as directed by the analyst and any equipment
required by the analyst to perform the four-stage clearance procedure (eg ladders).
A type H vacuum cleaner and buckets for decontamination should also remain inor around the airlock. Enough time should then be left to allow the work area tocompletely dry before the four-stage clearance procedure is carried out.

Disposal of asbestos waste
What is asbestos waste?
7.87 CAWR defines asbestos waste as being any amphibole or chrysotile
product that has been removed from its original place of use. Therefore any
asbestos product or material that has been removed from its original location
should be treated as asbestos waste. This includes debris, dust and associatedrubble and other mixtures where asbestos products are present. In England andWales, the revised waste regulations20 classify asbestos waste as ‘hazardous
waste’. In Scotland, asbestos waste is referred to as ‘special waste’ and isdefined in practice as >0.1% asbestos (w/w).21 If there is any doubt about about
the presence of asbestos in waste, it should always be treated as ‘hazardous’ or‘special’ waste.
7.88 Asbestos samples are not considered to be hazardous or special wasteby the Environment Agency (EA) or the Scottish Environment Protection Agency(SEPA) until there is an intention to discard them. Samples should still be labelled inaccordance with Schedule 2 of CAWR (see paragraph 7.91).
7.89 There are various other items that should be treated as asbestos waste.
These include all enclosure building materials (such as timber and sheeting) andany items that have been present (and unprotected) inside contaminated areasand cannot or will not be cleaned (including tools and equipment). Asbestos waste
items also include all disposable PPE used in the enclosure, transit and wasteroutes and in the hygiene unit. It also includes any disposable or discarded items
used in cleaning and decontamination such as cloths, wipes and towels. Waste
water from the buckets in airlocks should be disposed of through the filtereddrainage system in the shower of the hygiene unit.
7.90 In England and Wales, premises that generate >200 kg of hazardous waste
in a 12 month period have to be registered with the EA. This should be checked
before work starts. Where <200 kg of hazardous waste is generated from eachpremises, contractors can register as a ‘mobile service’. Contractors may also need
to apply for a waste processing licence (‘mobile plant licence’) from the relevant
environment agency (EA or SEPA) if removing ACMs from contaminated land. In
addition the EA or SEPA should be contacted for advice if it is intended to reuse
demolition rubble that is contaminated with ACMs.

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Box 7.4 UN-approved asbestos waste packaging

It is the consignor’s duty to ensure that dangerous substances are properly
packaged and labelled.
‘UN-approved’ packages have been subjected to tests to ensure their suitability
to withstand the handling associated with road transport. They will usually need
to be used in double layers (eg red bag inside clear bag) and have specified
means of closure (eg by PVC tape or ‘swan necking’ and taping). These details
should be obtained from the supplier.
Typically, approval details will be marked in the following way:
u
n

5H4
Y 		
		
x 		
S 		
** 		
GB
		
abcd

5H4/Yx/S/**/GB/abcd
is the code for plastic film bags
indicates suitability for packing group II and III substances (covers both
relevant UN numbers)
represents the maximum weight of contents in kg
means use for solids only
last digits of year of manufactureis the country of certification (could be another country. Symbols match
those for cars)
represents the certificate number

The bags should also be marked with the asbestos symbol (see Appendix 7.1)
and the CDG hazard placard shown in Figure 7.21.
Box 7.5 Exemptions to the requirement for UN packaging
Special Exemption 168

This exemption applies when asbestos fibres are either bonded or contained insuch a way that no fibres can become airborne in transit, namely:■■ whole asbestos cement sheets that are transported in a sealed skip;■■ articles with an asbestos component that cannot create airborne fibres intransit, eg a sealed fuse box containing asbestos rope or machinery with asealed gasket;■■ bonded materials such as bituminous floor tiles containing asbestos.
The limited quantity (LQ) exemptions

There are also specific exemptions from UN packaging requirements for small
quantities of asbestos (less than1 kg amphibole and less than 6 kg chrysotile).
The exemptions allow asbestos to be carried in alternative ‘fit for purpose’
packaging.
How to package and label waste
7.91 Asbestos waste is subject to labelling and packaging requirements inaccordance with Schedule 2 of CAWR and the Carriage of Dangerous Goods
and Use of Transportable Pressure Equipment Regulations 2004 (CDG).32 CAWR
requires asbestos items to be contained in ‘sealed containers’ which should bear
the asbestos warning label, shown in Appendix 7.1. In addition, CDG requires all
forms of asbestos to be contained in UN-approved packaging (as detailed in Box
7.4) unless they fall within the exemptions listed in Box 7.5.
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Figure 7.20 UN-approvedbags

7.92 In most cases, asbestos waste from licensed removal work will not qualify
for the exemptions from CDG requirements. Therefore the waste should be
double bagged using UN-approved packaging and placed in a sealed skip, freightcontainer or locked vehicle. Standard practice is to use red inner bags and clear
outer bags. The red bag contains the asbestos warning label. Bags should not
be over-filled or contain sharp objects which may pierce the material. Approved
packaging is available for up to 2 tonnes in capacity.
7.93
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The following protocol should be followed for bagging (or wrapping):

ensure that the waste material has been dampened down (in the case of AIB)
or is wet (a doughy consistency for lagging materials);
use waste bags directly beneath the work, and ‘containment’ sheets wherethese do not create other hazards;
ensure that there are sufficient suitable UN-approved bags and/or polythene
sheeting and means to seal the packages before work starts (see Figure 7.20);
place the waste carefully into a red waste bag and seal with strong tape. Wipe
down the red bag, place inside a clear asbestos waste bag and seal and clean
in the same manner;
if wrapping a large object which cannot fit into the asbestos waste bags,
ensure that the item is wrapped in two layers of strong polythene and that a red
asbestos waste bag or printed label (with the same information as the bag) issecurely attached to the package to indicate that it is asbestos waste. The item
must then be placed in a lockable skip or freight container;
ensure that the specific waste decontamination procedures are followed. The
procedures for cleaning waste bags or other wrapped waste are described inBox 7.6;
ensure that the waste bags are transported to the skip or vehicle via thededicated waste route;
do not take waste packages through the hygiene facilities;
make sure that your emergency procedures include a system for clearing up
any spillages that occur when a waste bag bursts or becomes punctured either
on site or in transit;
asbestos-contaminated rubble or soil should not be carried ‘loose’ in a skip.
This type of waste should be placed in large UN-approved bags (eg 2-tonne)
and then placed in a lockable skip or freight container.

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Box 7.6: Procedures for removing asbestos waste from the enclosure (see also

Figure 6.8)
Waste bags (and wrapped items) must be decontaminated before they are
removed from the enclosure. Decontamination will take place in the baglock
system which forms part of the enclosure. In most situations (transiting andnon-transiting), it should be performed in a three-stage baglock. The procedure
should be as follows:■■ the sealed waste bag (usually red and labelled) should be placed in the inner

stage of the three-stage baglock;■■ the bag should be wiped down and transferred into the middle stage of thebaglock;■■ the bag should be placed in a second bag (usually transparent), sealed andwiped down;■■ the double-bagged waste should be placed in the outer stage of the three-stage baglock;■■ the waste should be collected from the outer stage by the ‘outside’ worker andtransferred to the waste skip.
Appropriate PPE should be worn by the outside worker (see paragraph 5.13).
Where there is insufficient space for a dedicate three-stage baglock, thedecontamination should be carried out in the alternative baglock arrangement.
The design of the baglock will depend on the circumstances, eg transiting, nontransiting. Details are given in paragraph 6.22.
Transfer of waste to sealed skip or vehicle
7.94 Bags should not be overfilled. Once the waste packages are outside thebaglock they should not be left unattended. All such waste should be kept secure.
The best way to ensure this is to have a worker permanently based on the outsideof the enclosure who does not need to decontaminate to take the waste to the skip
or vehicle used for disposal. The skip or transport vehicle should be as close as
possible to the enclosure to reduce the risk of the spread of contamination and thepotential for musculoskeletal injuries. The following key points should be observedin relation to this part of the process:
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the ‘outside worker’ should wear appropriate PPE (ie RPE (eg FFP3), coveralls,
gloves and footwear and wet weather gear, if necessary) when handling waste;
keep the skip or vehicle locked;
ensure the skip or vehicle is as close to the enclosure as possible;
do not locate the skip or vehicle close to a sensitive area, eg in the middle of aschool playground;ensure that there are no sharp objects placed in the skip. A sealed bulkhead
should be provided in vehicles used to transfer waste to separate passengers
from waste materials. Tools and other equipment should also be segregated toprevent bags etc being ruptured during transit;
waste packages should not be thrown into the skip or vehicle. The route to the skip
should be delineated, as this will form part of the clearance test at the end of the job;
if there is no employee available on the outside of the enclosure to transfer
waste to the skip or vehicle, then the person putting the waste through thebaglock will have to carry out primary decontamination before taking the waste
to the skip or vehicle (see Chapter 8 for details of personal decontamination).

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Storage of asbestos waste
7.95 Asbestos waste can only be stored under the following circumstances:nn

on site in a locked skip or locked vehicle;
at a waste management facility, licensed or permitted by EA or SEPA.

Under no circumstances should asbestos waste be stored in an
enclosure, airlock or the hygiene facilities
Transfer for disposal
7.96 Companies transporting waste should ensure that they comply withthe relevant legislation and the guidance issued by EA and SEPA in relation toregistering as a waste carrier and maintaining an auditable trail to show where
the waste came from and its disposal point. All skips or freight containers holding
asbestos waste should carry the asbestos symbol as shown in Appendix 7.1.
7.97 All loads should be made secure. It is good practice to have skips or freightcontainers that are regularly used for asbestos waste to be used exclusively for that
purpose. HSE does not require them to be lined although they should be cleaned
out to remove all visible debris once they have delivered their load to the licensed
tip. Waste water from this process should be filtered and any residue should be
disposed of as asbestos waste.
7.98 If a package or bag bursts during transit in a vehicle, sealed skip or freightcontainer, the vehicle, container or skip will need to be cleaned out and visibly
inspected before it can be reused. A vehicle would also require a disturbed air test
to be carried out.
Carriage of dangerous goods requirements
The dangerous goods safety advisor
7.99 If a contractor is loading or transporting more than 333 kg of crocidolite oramosite (ie blue or brown) asbestos or 1000 kg of chrysotile (white) asbestos waste
to which the CDG regulations apply, then a suitably trained transport of dangerous
goods advisor will have to be appointed. The advisor should help to draw up
procedures to load and/or transport waste, liaise with other safety advisors andwrite reports about any incidents involving the transport of the waste. This will apply
to contractors who are registered waste carriers and transport waste in their own
vehicle or who provide their own skip and skip lorry to transport waste to a licensed
tip. If the work is sub-contracted to a registered waste carrier and the contractor
only puts the packages into a sealed skip, a transport of dangerous goods advisor
will not be required.
Transport rules
7.100 The CDG regulations require all fibrous waste to be transported under
the conditions set out in the flowchart in Appendix 7.2 which is also summarised
below:
nn

where the maximum weight of the vehicle exceeds 3.5 tonnes, the drivertransporting the waste will need to have a dangerous goods Vocational Training
Certificate (see Are you involved in the carriage of dangerous goods by road orrail?);33 the vehicle will need to have suitable fire extinguishers; a ‘Tremcard’ (ieinstructions in writing) (the information to be provided is listed in Appendix 7.3)
should be carried in the vehicle cab; orange panels should be displayed on thefront and rear of the vehicle and hazard placards (as shown in Figure 7.21) on
all four sides of any skip loaded onto the vehicle;
where the vehicle weight is less than 3.5 tonnes and more than 333 kg of
crocidolite or amosite (ie blue or brown) asbestos or more than 1000 kg ofAsbestos: The licensed contractor’s guide

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Figure 7.21 CDG hazard
placard9nchrysotile (white) asbestos is being carried, orange panels and hazard placards
have to be displayed but the driver will not need dangerous goods training;where the vehicle’s maximum weight is less than 3.5 tonnes, and less than
333 kg of amphibole and less than 1000 kg of chrysotile asbestos are carried,orange panels and hazard placards do not have to be displayed.

Environment Agencies’ requirements
7.101 The Environmental Protection Act22 requires that a registered waste carrier
is used for all construction and demolition waste. The nearest office of EA or SEPA
should be contacted for further details of their administrative requirements. A listof regional offices can be found on the agencies’ websites: www.sepa.org.uk andwww.environment-agency.gov.uk. The key points for asbestos waste are given inBox 7.7.

Site assessment for reoccupation (Four-stage clearance procedure)
7.102 Following asbestos removal, the premises must be assessed to determine
whether they are thoroughly clean and fit for reoccupation (or, as appropriate,
demolition). Once the licensed contractor is satisfied that the area is clean andready for future use, the area should be assessed by an independent organisation
which is accredited by UKAS as complying with ISO 17025.34 All air measurements
should comply with the ISO 17025 standard. If this assessment of the workplace ispassed as satisfactory, then a certificate of reoccupation is issued. The certificate
is issued to the contractor and, as appropriate, to the client where the latter has
engaged the analyst.
7.103 The clearance certification process is a vital component in asbestos
removal work. The issue of a certificate of reoccupation by an impartial andcompetent organisation provides the crucial reassurance and security to thesubsequent building users. The multi-stage certification process is designed toallow the inspection and assessment to be performed in a structured, systematicand consistent manner. The contractor should not arrange for the site clearance
certification procedure to start until satisfied that the area is clean and dry.
Box 7.7 Waste: Key points■■ Make sure that waste is properly bagged and/or wrapped with the appropriate

UN-approved markings.
■■ Waste bags or packages should be removed through the baglock.
■■ Position the skip, container or vehicle as close to the enclosure as possible.
■■ Ensure that no sharp objects can burst bags or packages during transit.
■■ Ensure that the skip, container or vehicle is kept locked.
■■ All waste should be taken to a licensed or permitted waste management facility

by a registered waste carrier and consigned appropriately.
■■ A waste processing licence may be needed for some waste management

activities.
■■ In England and Wales the premises of asbestos waste generation must be

registered as a hazardous waste producer with the EA before the waste istransported.
■■ You may require a transport of a dangerous goods advisor if you load and/ortransport asbestos waste to which the CDG regulations apply.
■■ You can only store asbestos waste on site in a locked skip, container or vehicle
or at a waste transfer station.
■■ Ensure that you have emergency procedures for clearing up any burst bags or
packages.

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7.104 The analyst and the contractor need to co-operate and support eachother during this process. Each also needs to understand the respective roles andresponsibilities. It is the responsibility of the contractor to thoroughly and diligently
clean up the work area. The analyst’s role is to provide independent verificationthat the area is clean and suitable for subsequent use. It is not the analyst’s roleto oversee the final clean of the area. It is the analyst’s role during clearance
certification to direct the contractor to those matters which require attention toensure successful completion of the process. The analyst should allow sufficient
time for clearance certification to be performed.
7.105 There are four stages to the site certification for reoccupation procedure:Stage 1: Preliminary check of site condition and job completeness;
Stage 2: A thorough visual inspection inside the enclosure/work area;
Stage 3: Air monitoring;
Stage 4: Final assessment post-enclosure/work area dismantling.

Stage 1: Preliminary check of site condition and job completeness7.106 Initially the analyst needs to establish with the contractor the scope of thework that has been carried out. This must be done by examining the contractors’
POW.7 (Full information on contractors’ plans of work is given in paragraphs
3.16-3.26). Regulation 7(2) of CAWR7 states that the POW should be kept at
the premises until the work is completed. Paragraph 38 of Work with asbestos
insulation, asbestos coating and asbestos insulating board. Control of Asbestos
at Work Regulations 2002. Approved Code of Practice and guidance12 states that
the POW should be brought to the attention of anyone carrying out the four-stage
certification procedure. It should be clear from the POW:nnnwhere the asbestos to be removed was;
if any asbestos materials were to remain in situ; andwhat the asbestos materials removed were.

7.107 If there is no POW on site or if the contractor refuses to make it available,
the inspection should either stop until such time as a POW is made available
or a ‘failed’ certificate of reoccupation issued with the reason for the failure
noted.
7.108 The analyst should record the scope of the work on the site certificate forreoccupation. A diagram or photos should be appended so that the scope of
the work is quite clear. A copy of the diagram from the contractor’s POW would
meet this requirement. If there is no diagram on site, the analyst should preparea diagram. The diagram should contain the main features. It should show theenclosure (or work area) including airlocks and baglocks, transit and waste routes,
and skip and hygiene facilities. It should provide details of sizes or dimensions. An
example of a diagram is shown in Figure 7.22. The analyst and contractor should
agree the content of the diagram and both should sign and date it.
7.109 When the scope of the work has been understood and verified, the analyst
should ensure that the hygiene facilities are still intact, operational and clean. The
clean end of the unit should be checked for cleanliness, hot and cold water andheating. The shower area and dirty end should be inspected either by externalviewing (from the clean end in the case of the former) or by entering wearing theappropriate RPE and PPE. These areas should be clean and free from stored items
and the NPU should be operating. The analyst should then check the surrounding
areas to the enclosure, including the transit and waste routes, and the areas
immediately adjacent to the enclosure (see also Boxes 7.8 and 7.9). The purpose ofthis inspection is to check for obvious signs of contamination arising from the work;
either through leaks in the enclosure, burst waste bags or debris from inadequate
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decontamination procedures. This inspection does not require the detailed visual
examination which is necessary inside the enclosure or work area.

Figure 7.22 Recording of the site layout as a diagram, (a) shows the 3-dimensional layout and (b) is an example of how thesite could be recorded as a clearance diagram. Dark areas show work areas and light areas show other areas which need to
be inspected(a)Airlocks
Enclosure wall
Plant room

CanteenGround floor
NPU
First floor

Skip

DCU

(b)

Tent
Airlocks

Work areas
For inspection
Plant
room

CanteenNPU
NPU
Main car park

Skip
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Drawing V01

Layout of asbestos
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Box 7.8 Multi-job sites

Where there are several jobs ongoing at the same site, using, eg the same
waste skip, it will not be possible for a Stage 1 inspection to be carried out inthat area, as it is still being used. In this case the Stage 1 certificate should state
why that area has not been inspected and clearly identify the area that has beeninspected. This principle would apply wherever there are common areas still inuse. Such information should be transparent and it should be recorded on thecertificate of reoccupation.
7.110 The integrity of the enclosure should also be checked. If any asbestos
debris is found in the surrounding areas it should be cleared up immediately by thecontractors. Any breach in the integrity of the enclosure should be repaired before
Stage 2 is started. The analyst should make sure that the air extraction equipment
is in situ and in operation. Air extraction equipment should be switched off justbefore starting the Stage 3 air monitoring and should not be removed until the third
stage of the site certification procedure has been completed and the enclosure
is being dismantled. The pre-filters on the air extraction equipment should be
replaced with new ones before the final clean by the contractors.
7.111 The analyst should examine the enclosure through the viewing panels (orCCTV monitor) before entering in order to gain an initial impression of the job
completeness. Items to look out for include:
n
n
n
n
n
n
n

waste remaining in the enclosure;visible debris on the surfaces;
inadequate lighting to conduct a visual inspection;
essential equipment such as ladders or scaffolding are still present so it ispossible to inspect all areas;
puddles of water, wet patches and leaking pipes;
evidence that sealant has been applied to exposed surfaces;
potential hazards inside the enclosure.

7.112 If any of these items need to be actioned, they should be dealt with before
the enclosure is entered. The analyst should direct the contractor to the mattersneeding to be rectified. The analyst should also discuss with the contractor if anyof the items were identified in the POW as needing special attention (eg ingressof water). The type of action needed to overcome these problems is given inparagraphs 7.123-7.130. The analyst must make a formal record of the scenarios
encountered and the discussions and actions that took place to rectify them. If
viewing inside the enclosure is not possible or is limited (viewing panels or cameras
are either absent or are insufficient and do not allow views of all of the work area),a note of this should be made in the analyst’s site record and the above items
considered when entering the enclosure in Stage 2.

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Box 7.9 Conditions where an inspection of the transit routes should take place
Conditions should allow the identification of obvious asbestos debris along transit
and waste routes. Under normal circumstances, rain or damp ground should
not prevent a Stage 1 inspection as the analyst is looking for visible debris, notfine settled dust. An inspection at night would not be a problem if the routes
were well-lit. If, however, the analyst felt that conditions did not allow reasonable
inspection, eg insufficient light, then it should be delayed until the conditions
are suitable, eg the following day. In the very rare occurrences where a delay
is likely to be significant, eg several days (eg due to snow covering), then theanalyst should record the situation in the certificate of reoccupation and continue
with the remaining clearance stages. The certificate of reoccupation should
be issued as appropriate. However, the analyst and the contractor will have toreturn and complete Stage 1 (and Stage 4 if appropriate) as soon as possible
after the conditions allow. The ACOP, Work with asbestos insulation, asbestos
coating and asbestos insulating board. Control of Asbestos at Work Regulations
2002. Approved Code of Practice and guidance12 provides for this variation fromthe norm in paragraph 157, where it states ‘Site clearance certification should
normally be carried out in four successive stages, with the next stage only beingcommenced when the previous one has been completed.’
If transit and waste routes are strewn with debris that could be mistaken forasbestos, or such that it is difficult to inspect for debris, the analyst should
request that the routes be cleared to allow for adequate inspection.
The inspection is for obvious asbestos contamination and debris, not anyother kind of debris.

There is no point in entering the enclosure until these problems
have been rectified
7.113 Findings at Stage 1 should be recorded on the certificate of reoccupationand verified with the contractor before moving onto the second stage. There should
be confirmation that the POW has been inspected and that the air extraction
equipment, hygiene facilities and work areas are intact and operating. This stage
should also contain a record of findings of the inspection of the skip/waste route,the transit route, hygiene facilities and the outside of the enclosure. A note should
be made of any remaining asbestos that was outside the scope of the work.
7.114 Only when the analyst is satisfied with the Stage 1 inspection, should he/she enter the enclosure to carry out the Stage 2 inspection. The analyst should
generally be entering an area that is free of all asbestos and should not normally
be expected to have to undergo full decontamination on exiting the enclosure.
However, if the site is found to have extensive debris and surface contamination
remaining, it is important that the analyst terminates the Stage 2 visual inspection
and leaves the enclosure before any significant disturbance or clean-up takes
place. Failure to do this will mean the analyst could be contaminated by thecontractors’ activity and will need to follow full decontamination procedures onleaving the enclosure. Detailed information on decontamination procedures foranalysts is given in Asbestos: The analysts’ guide for sampling, analysis andclearance procedures.8

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Figure 7.23 Analyst
carrying out a visualinspection inside an
enclosureStage 2: Thorough visual inspection inside the enclosure/work area
7.115 This is the stage at which the thorough visual inspection of the enclosure
or work area takes place. It is the most significant part of the clearance procedure.
The analyst must check:nnn

the completeness of the removal of the ACMs from the underlying surfaces;
for the presence of any visible asbestos debris left inside the enclosure andairlocks or work area;
for the presence of fine settled dust.

7.116 The removal process will have given rise to the spread of asbestos dust
inside the enclosure. Residual dust may still remain on any unprotected orinadequately cleaned surfaces. Such dust presents an ongoing risk to building
occupants. Therefore a thorough visual examination of all surfaces should be
performed. It should involve a close and detailed inspection across all parts of theenclosure kneeling down or using ladders where appropriate (see Figure 7.23). All
items should be checked. The inspection can be assisted by using a torch andby running a fingertip across the surfaces to check for presence of fine dust (seeFigure 7.24). Awkward or difficult locations must not be excluded. Baglocks andairlocks should be included.

Figure 7.24 A torch being
used to illuminate fine settled
dust

7.117 The analyst should be accompanied during the thorough visual inspection
by a representative of the contractor, who can rectify any minor problems found,such as:nnholes in the enclosure not visible from the outside;small amounts of dust or debris found during the course of the inspection.

7.118 The analyst will have to make judgements on the extent and significanceof dust and debris found during the inspection: whether it is minor and can becleaned up during the course of the inspection, or whether it is more substantial
and is indicative that the final clean has not been undertaken thoroughly enough.
It is important to remember that it is the duty of the contractor to undertake thefinal clean and carry out a thorough visual inspection before requesting a fourstage site certification for reoccupation. If it is clear that this has not been done,
the analyst should withdraw and fail the enclosure, citing what needs to be done
before another inspection is undertaken. The risk that the analyst undertaking aninspection will miss some contamination is increased if he/she has to stop and getcleaning done every few minutes. They should withdraw and let the contractors
clean and re-inspect before starting a new visual inspection.
7.119 Essential equipment to be used inside the enclosure includes:nnna torch - the torch beam when shone along a surface at a shallow angle isuseful in identifying fine settled dust on surfaces; it can also augment thelighting in the enclosure;a screwdriver - this is useful for poking behind pipes and into crevices to help
inspect these difficult-to-see areas;a mirror - this can be useful in inspecting difficult-to-see areas.

7.120 Locations where asbestos dust and debris are commonly found during
thorough visual inspections are shown in Figure 7.25. Asbestos dust and debris
may also be found in the folds of sheeting used to construct the enclosure.

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7.121 Equipment that must remain in the enclosure to help inspection includes:
n

n
n

n

stepladders/scaffolding - depending on the height of the enclosure one or theother will be needed to allow safe access and to inspect the ledges, pipework
etc above head height;
lighting - a thorough inspection needs lighting; a torch alone is not enough. The
torch should be used to supplement the background lighting, not replace it;
vacuum cleaner and other cleaning materials - this will allow the contractor
to clean any minor amounts of debris identified by the analyst immediately;a vacuum cleaner must also be available for preliminary decontamination onleaving the enclosure;buckets of water and sponges and brushes or wipes in the airlock to aid
preliminary decontamination, following the visual inspection.

Figure 7.25 Boiler room showing locations where asbestos dust and debris are commonly found during a thorough visualinspection

9
■

6
■

8
■

7
■

3
■

2
■

1
■

10
■

5 ■
4
■

■
1
Backs of pipes and vessels■
2
Support brackets and clamps on pipes and vessels■
3
Nuts and bolts or flanges and hatches of vessels and pipework■
4
Screw holes, or around nails and battens for AIB tiling■5
Cable trays and conduits, especially if they have a metal mesh construction■
6
All horizontal ledges, shelves, window sills etc■
7
The undersides of boilers and tanks, either attached or loose■
8
Rough porous brickwork, eg breeze block and rough concrete■
9
Holes in walls etc, where pipes, cables or steelwork pass through■10 Drains, sumps and culverts

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How long should a visual inspection take?
7.122 The analyst must ensure that sufficient time is available for the visualinspection. A detailed visual inspection can be time-consuming, and the length oftime needed will depend on the size and complexity of the job. A thorough visual
search of all areas of the enclosure is required to be confident that an area is clean
and free from asbestos debris and fine settled dust. A single panel removed frombehind a domestic boiler within a 2 m2 enclosure with smooth surfaces and nothingelse within the enclosure is unlikely to take more than 10-15 minutes. Even a small
boiler house should not take less than about 1.5 hours if inspected thoroughly. A
large plant room, chemical plant or power station may take several days. During
a large clearance, analysts should leave the enclosure, decontaminate and take abreak every 2-3 hours. The time spent carrying out a visual inspection should berecorded.
Problems commonly encountered during visual inspections
7.123 Paragraphs 7.123-7.130 provide guidance on several issues which may
be encountered during visual inspections. Potential problems can arise due toinsufficient planning and preparation. Clearance should be considered by thecontractor at the very outset of the job. There is a requirement for the contractor toconsider clearance in the initial assessment of the work (ACOP, Work with asbestos
insulation, asbestos coating and asbestos insulating board. Control of Asbestos
at Work Regulations 2002. Approved Code of Practice and guidance,12 paragraph30). The contractor should be looking to identify those matters which will inhibit or
impede clearance, eg wet enclosures, loose or naturally dusty surfaces, voids inceilings which contain mineral wool, congested plant rooms which contain multiple
pipes or equipment. These matters can normally be eliminated or resolved moreeasily before the work starts.
Wet enclosures
7.124 This is a problem commonly cited by analysts when undertaking clearances.
The ACOP, Work with asbestos insulation, asbestos coating and asbestos
insulating board. Control of Asbestos at Work Regulations 2002. Approved Codeof Practice and guidance12 states that an enclosure, where practical, should beclean and dry. However, the enclosure is sometimes wet. There are a variety ofreasons for this: there may be a leaking pipe; sealant may have been sprayed in theenclosure; or there may be groundwater seeping through. If groundwater is present
there may be little that can be done to render the enclosure completely dry, but it
may be necessary for the contractor to use a pump to prevent the area flooding.
However if there is a leaking pipe, there are two scenarios:nn

If it is identified before work is carried out, it can be pointed out to the clientand fixed before work begins. It can also be explained to the asbestos removal
contractors that they will be unable to obtain a certificate of reoccupation if
the leak is not fixed. If the situation is further complicated by the fact that thepipe is lagged with asbestos, then a preliminary removal job can be carriedout. A small enclosure should be built and a section of lagging removed using
a glovebag. This will allow plumbers to carry out their work once the area has
obtained a certificate of reoccupation.
If the leak is identified during the course of the work, work should cease andthe area be cleaned. The plumber can then be accompanied into the enclosure
by the contractor. The air extraction system should stay on. Plumbers shouldhave suitable training in the use of the RPE and PPE to allow them to carryout their work safely. A leaking pipe should be no excuse for a wet enclosure.
An enclosure will fail a visual examination if it is wet and the cause isremediable.

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Sprayed sealant
7.125 Paragraph 161 of the ACOP, Work with asbestos insulation, asbestos
coating and asbestos insulating board. Control of Asbestos at Work Regulations
2002. Approved Code of Practice and guidance12 also states that sealants should
not be sprayed before a visual inspection or disturbed air tests. The only exception
to this is where there is sufficient non-asbestos dust (eg from concrete) to causea failure in the air test. The analyst has discretionary powers and, after due
consideration and air testing, can allow sealant to be used in these circumstances(see paragraph 7.137). The circumstances should be recorded on the certificate ofreoccupation and the air test should proceed. If an analyst arrives on site to carryout a visual inspection and the enclosure is still wet due to sealant being sprayed,
the analyst must fail the area and inform the contractor that the Stage 2 inspection
can only be carried out when the sealant has been washed off and the enclosureis dry. If the sealant has already dried, the analyst will have to fail the site andconsider the way forward. If the evidence suggests that the sealant is protecting asignificant amount of asbestos dust which will cause risk to subsequent occupants,
then the sealant will have to be removed and the area recleaned. The client should
be informed.
Enclosures with loose rubble flooring
7.126 The assessment should identify work areas where the flooring is loose
rubble, eg in an undercroft. In these circumstances the rubble should be removed(to a specified depth) as part of a pre-clean of the site. The loose flooring would
then be sealed with an impervious layer, eg metal or hardboard sheeting, before
the asbestos work begins. If it was not possible to remove the rubble due to thecondition of the remaining ACM or space limitations, then the matter should be
addressed in the assessment. The POW should identify the procedure to remove
the rubble and loose soil after the ACM removal has been carried out. In thesecircumstances, it would be prudent for the contractor to consult with the analyst
before starting the work. If an analyst arrives on site to carry out the four-stage
clearance certification, without prior discussion and agreement of the proceduresfor clearance, it will be impossible to pass such an area according to the standard
required in a Stage 2 inspection. The analyst will have to fail the site and liaise withthe contractor and/or client to organise the removal of a specified depth of the
rubble/loose flooring before the formal inspection begins. The depth of rubble to be
removed will depend on the level of contamination. The analyst can then check theremaining flooring for signs of asbestos contamination. If the analyst is satisfied thatthe contamination has been removed, the flooring can then be sealed and Stage 2
visual can formally start.
Asbestos remaining in enclosures (by design)
7.127 There may be occasions when some asbestos is to remain in situ in theenclosure. It may be that only damaged asbestos lagging is being removed frompipework, and that undamaged material is to remain; or it could be that asbestos
ceiling tiles are being removed, but a fire door with an asbestos cement panel isbeing left in place. In these circumstances the ACM should be labelled that it isasbestos and that it is to remain. The item can then be checked by the analyst
against the work plan and recorded on the certificate of reoccupation.
Asbestos waste remaining in enclosure
7.128 On occasions, it may be necessary to retain asbestos waste (bagged or
wrapped) within the enclosure until Stage 4 of clearance certification starts and theenclosure can be removed. This situation may arise when oversized waste (such aslengths of pipework or large AIB panels) cannot be removed through the baglock
system. The items should remain in the enclosure and be subject to inspection
along with other items to make sure they are free of asbestos debris on the outsideof the wrapping. The items will also need to be moved to allow the analyst to
inspect the underlying surfaces.
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Inaccessible asbestos
7.129 Where asbestos has been spray applied, there are often crevices or holes
through walls where pipe work or girders run. These may contain asbestos but are
impossible to clean so that all asbestos is removed. In these cases, the analyst
may permit the use of non-flammable sealant such as foams or plaster to fill thehole and seal the asbestos within it. However, the analyst should be satisfied
that as far as reasonably practicable, the asbestos has been removed before thesealant is applied. The client for the contract (eg building occupier) should be
informed that this is the proposed course of action before the encapsulation takes
place. It should be in the POW. The location of the sealant and remaining asbestos
should be noted on the certificate of reoccupation, so that the client can record thepresence of the asbestos in the management plan. If an analyst arrives on site tofind that holes around the area where the sprayed asbestos was applied have been
plugged with foam or other sealant, the contractor should be instructed to remove
the sealant before the Stage 2 inspection begins.
Use of encapsulant and sealant
7.130 Where asbestos has been sprayed onto porous surfaces (eg breeze blocks)
or onto tar, it is almost impossible to remove all the asbestos, sufficient to passa visual inspection (see Figure 7.26). In these cases the analysts, having satisfied
themselves that further removal is not reasonably practicable, should advise thecontractor and/or client to seal the residual asbestos with a permanent proprietary
sealant. The visual inspection can then begin again once the sealant has been
applied and dried. Encapsulation of asbestos in these instances should not takeplace before the analyst has seen the residual asbestos.

Figure 7.26 Remnants ofasbestos on breeze blocks

Figure 7.27 Air sampling
during clearance

7.131 The findings of Stage 2 of the inspection should be recorded on thecertificate of reoccupation. There should be confirmation that the airlocks andenclosure are free from visible debris and contamination, that all ACMs have been
removed and that the interior surfaces of the enclosure are free from visible debris
and settled dust. As for Stage 1, if problems are encountered during the Stage 2
inspection, the analyst must make a formal record of the scenarios encounteredand the discussions and actions that took place to rectify them. The analyst should
also make specific comments on the certificate of reoccupation if any asbestos is
to remain (see paragraphs 7.128-7.129) and clearly identify the locations of theseareas with a recommendation that this information should be entered into the
management plan/asbestos register.
Stage 3: Clearance indicator air sampling for the certificate ofreoccupation
7.132 Air sampling takes place once a thorough visual inspection has been carriedout and the analyst is satisfied that all the asbestos in the POW has been removed,
and there is no visible debris or layers of settled dust (see Figure 7.27). The lowest
airborne respirable asbestos concentration that the method described in Asbestos:
The analysts’ guide for sampling, analysis and clearance procedures8 can reliably
quantify is 0.01 fibres/ml, for a sample volume of at least 480 litres passed througha filter with an effective diameter greater than 20 mm. In most cases it is reasonably
practicable to clean the working area thoroughly enough for the respirable
airborne fibre concentration after final cleaning to be below that limit, using theapproved measuring method. Therefore a value of 0.01 fibres/ml is taken as the‘clearance indicator’ threshold, and a site should not normally be regarded as fit forreoccupation until the asbestos in air measurements are below this level.
7.133 Details of the equipment to be used to carry out the sampling and analysis
are given in Asbestos: The analysts’ guide for sampling, analysis and clearance
procedures.8 The strategy for sampling and dust disturbance and sample analysis
are also given in Asbestos: The analysts’ guide for sampling, analysis and clearance
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broom and brushing the surface from which the asbestos was removed and anyother higher level horizontal surfaces (see Figure 7.28). Brushing should also takeplace on horizontal surfaces where the dust may have settled or collected or where
there is suspicion of surface contamination, and on surfaces in close proximity to
the sampling equipment. The broom and/or brush used should be made out of
man-made fibre and should be used to give a representative simulation of cleaning
activity. For enclosures with floor areas greater than 20 m2 a long-handled broom
should be used to sweep the floor, for both ergonomic and practical reasons.
7.134 The dust disturbance should be carried out as described in paragraphs
7.135-7.136. The dust-raising activities undertaken and their duration should berecorded on the certificate of reoccupation. On some surfaces, brushing may
generate significant amounts of particulate which may obscure the filter. If this is
the case, sampling strategies may need to be modified to take this into account.
Appropriate PPE should be worn by the person conducting the disturbance test.
7.135 The purpose of the disturbance activity is to ensure that workers,
occupants, cleaners and members of the public using the area in the future are
not exposed to asbestos as a result of ineffective removal and cleaning. A realistic
simulation of a possible future activity that may produce high airborne dust andfibre concentrations is the brushing or sweeping of surfaces. Brushing should
be carried out in a manner that is consistent with normal cleaning activities in abuilding. Brushing should take place in all of the following locations: all surfaces
from where the asbestos has been removed, horizontal surfaces where the dust
may have settled or collected or where there is suspicion of surface contamination,and surfaces in close proximity to the sampling equipment. These dust-raising
activities should be substantial enough to raise fine settled dust (if it is present) fromsurfaces, and should be commensurate with the size of the enclosure. They shouldtake place for a duration of at least 1.5 minutes for each measurement point inside
the enclosure, near the start of each full hour of sampling, or each time a new filter
is used in an area. For larger enclosures there is likely to be more than one person
carrying out the dust disturbance work, so the same total surface area will be
disturbed but in less time. This means the total time of the disturbance is unlikely to
exceed around 10-15 minutes each hour.
7.136 All brushes used for raising dust should be considered as being
contaminated and should generally be disposed of as asbestos waste. However
some brushes may have detachable screw handles. Where the handle isconstructed from a material which could be effectively decontaminated (eg plastic)
then this part may be reused after thorough cleaning. Brush heads, irrespective of
the composition, should always be disposed of as asbestos waste.
Dusty enclosures
7.137 There may be occasions when the surface in the work area is a source of
non-asbestos dust that would generate unreadable filters. The presence of nonasbestos dust would be noted at the thorough visual inspection. The analyst has
to be satisfied that the dust is non-asbestos. However, the analyst should proceedwith air sampling as normal. If this produces unreadable filters, the analyst should
consider sampling for shorter periods with paired samplers, so that the dust loadingon each filter is reduced. If the samples fail again because of the dust loading, thenthe spraying of surfaces with a sealant should be considered. If a sealant is used,
the air test should not be carried out until the sealant is dry (see paragraph 7.125).

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Figure 7.28 Analyst
carrying out disturbance bybrushing during clearance

Assessment of air sampling results
7.138 After air sampling, the analyst will check the final flow rate and collectsamples for phase contrast microscopy analysis. The analyst will count the fibres ina minimum of 200 graticule areas and report the calculated fibre concentrations foreach sample. The analyst will also produce a clear statement whether the enclosure
has passed or failed, relative to the clearance indicator value (0.01 f/ml).
Leaks in enclosures
7.139 Under normal circumstances, the air extraction equipment should be turned
off and capped during the air test. The analyst should check that the pre-filter waschanged before the final clean. However, if, in the opinion of the analyst, switching
the air extraction system off would compromise the integrity of the enclosure, andthere are people near the enclosure who may be exposed to airborne asbestos
fibres above the clearance indicator as a consequence, the analyst can direct thecontractors to leave the system switched on during the air test. Any decision toleave the air extraction system switched on should be recorded, with reasons why,on the certificate of reoccupation.
Stage 4: Final assessment post-enclosure/work area dismantling
7.140 Once the enclosure (or work area) has passed the visual inspection (Stage2) and air monitoring (Stage 3), the enclosure can be dismantled. Under normal
circumstances, the analyst will probably remain on site during dismantling (unlessthe deconstruction is not to take place for some time). If the analyst is close to thedismantling work, appropriate PPE should be worn as trapped pockets of asbestos
could be released during the physical disturbance. Reassurance sampling could be
carried out during the dismantling procedure to check for any release of airborne
asbestos. After the enclosure has been removed, the analyst should visuallyinspect the area to ensure it is clean. At this stage the analyst is looking for obvious
asbestos debris such as from the sheeting of the enclosure as it was dismantled
or from debris which has been missed during cleaning. The analyst should also
re-inspect the waste route and transit route for asbestos debris.
7.141 Where there is some debris, this can be cleaned by the contractor’s
employees, wearing appropriate PPE including RPE, immediately using a type H
vacuum and wiped with a wet disposable cloth. If the area is too contaminated toallow immediate cleaning without the prospect of spreading contamination, the siteshould be failed, re-enclosed, re-cleaned, and the visual inspection and disturbed
air test repeated.
7.142 If there are fuse boxes or switches within the area and the analyst suspects
they may be contaminated, a qualified electrician should be made available toisolate the boxes, so they can be inspected.
7.143 The analyst should record what has been inspected, what was found andthe outcome on the certificate of reoccupation.
Certificate of reoccupation
7.144 Once all four stages of the clearance procedure have been completed
satisfactorily, the analyst should issue a certificate of reoccupation. Each stageof the certification should have been completed in sequence, to ensure that the
information included is as complete as possible. The information should be clear
and unambiguous so all parties know the scope and extent of clearance and any
particular matters which have been dealt with.
7.145 A template for a certificate of reoccupation setting out the details it should
contain can be found in Asbestos: The analysts’ guide for sampling, analysis andclearance procedures8 (Appendix 3). If one of the stages fails, the reasons forthe failure should be entered and the remaining stages struck through. A signed
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acknowledgement of the failure should be obtained from the contractor’s site
representative (usually the site supervisor). If the failure occurs at either Stage 1
or 2 of the process, the inspections (both Stage 1 and Stage 2) will need to berepeated. If a new analyst carries out the work, the whole procedure should startagain. If the site fails at Stage 3 or 4, it is only necessary to repeat these stages
until both have passed. The analyst will then need to cross-refer to, and append
the certificate where the Stages 1 and 2 were passed. It is very important that thecontractor’s representative acknowledges the outcome on each certificate issued,
whether for a pass or a failure, as this provides evidence of when the outcome
was communicated. The certificate will provide documentary evidence of thework undertaken by the analyst and should be retained by the analyst. Copies ofeach certificate must be issued to the contractor and, as necessary, to the client
employing the analyst. This may be done after the analyst has left the site, provided
the contractor’s representative has acknowledged the outcome. Each certificate
should bear a unique number.
Inspection certificate for the hygiene facilities
7.146 Once the certificate of reoccupation has been issued, the analyst can begin
the clearance of the hygiene facility. This should be inspected and air tested. The
air test should be accompanied by disturbance of surfaces in the dirty and shower
areas. Obviously there is no requirement for a four-stage certification procedure
here, as Stages 1 and 4 are carried out as part of the main certification forreoccupation. Only Stages 2 and 3 of the procedure are required.
7.147 The hygiene facility should be clean and dry before the inspection takes
place and any potentially asbestos-contaminated materials removed (eg bags
containing used coveralls, used/discarded respirator filters, transit clothing). It is
recommended that the unit is entered through the clean end to check that thisarea is clean and free of bagged materials, before carrying out a detailed clearance
in the shower area and dirty end. The clearance should be carried out using thesame criteria as for enclosures. If the inspection shows that no dust and debris arepresent, clearance air sampling should be carried out in the shower area and dirty
end. For very small units where the combined floor area of the shower and dirty
areas is less than 10 m2, one air test is sufficient if the door between the showerand dirty areas is propped open and the sample head is positioned in the doorway.
Where the combined floor area of the shower and dirty end exceeds 10 m2, asample in each of the shower and dirty areas should be taken. A minimum air
volume of 480 litres should be sampled for each sample. During air sampling, theextraction in the hygiene facility should be switched off and capped and surface
disturbance should be carried out using a brush for 1.5 minutes for each sample. A
separate inspection certificate should be issued for the hygiene facility. The hygiene
facility should normally be subjected to the inspection and air sampling before it is
moved off-site (see paragraph 7.147). The analyst should review with the contractor
whether or not the hygiene facility is to remain on site following the issue of theinspection certificate and a note of this made on the certificate.
7.148 Where, for security reasons, hygiene facilities are not left on site overnight,
inspection certification is not required until the end of the contract. In thesesituations, information on where the hygiene facility is to be stored overnight andother arrangements should be included in the POW sent to HSE with the ASB5
notification. Further information on this can be found in paragraph 8.40.

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APPENDIX 7.1: LABELLING REQUIREMENTS FOR PLASTIC BAGS/SACKS CONTAININGASBESTOS WASTE
Waste blue asbestos (crocidolite) UN 2212
Waste brown asbestos (amosite) UN 2212
Waste white asbestos (chrysotile) UN 2590
Carriage of Dangerous Goods and Use of Transportable Pressure Equipment Regulations 2004.32

White ‘a’ on a black
background								

h140%HStandard wording in white and/or
black on a red background

5 cm
H

h2
60%H

2.5 cm
50%H

The dimensions in millilitres of the label shall be those shown on the diagram, except that larger measurements
may be used, but in that case the dimension of the label indicated as h, on the diagram above, shall be 40% of
the dimension indicated as H on that diagram.
The label shall be clearly and indelibly printed, so that the words in the lower half of the label can be easily read,and those words shall be printed in black or white.

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APPENDIX 7.2: ASBESTOS WASTE FLOW CHARTS
Procedure for dealing with asbestos waste

WASTE ASBESTOSEngland andWales

Scotland: Is the content greaterthan 0.1% by weight?

YES

NO

Waste Regulations apply:

Waste duty of care applies22- Waste consignment
note required- contact EA/SEPA
for more information

Whoever transports the waste (you or a haulage contractor) must be
registered as a waste carrier
Contact EA/SEPA for more information

Is the asbestos waste combined or fibrous?

Is the waste in anatural or artificial binder so as
to prevent the escape of
hazardous or respirable fibres?

Transport and packaging:
FIBROUSNOYES
CDG does not apply

See expanded box
on page 154

FIBROUSCOMBINED

Transport and packaging:
COMBINED

Transport asbestos
waste as per timetable on the
Waste Consignment Note andkeep copies for
3 years

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The waste is dangerous for transport, CDG applies

Asbestos cannot be transported in bulk, it must be packed in UN-approved
packages displaying:- Proper shipping name- Class number- Hazard placard (see Figure 7.21)

Does the vehicle in which
the waste is to betransported have a maximum weightin excess of 3.5 tonnes?

FIBROUSTRANSPORT AND PACKAGING: FIBROUS- Driver to be trained forClass 9 Dangerous Goods

YES- Vehicle to be fitted with a
2 kg dry powder
extinguisher in cab
and 6 kg elsewhere *NO- Emergency information(Tremcard) to be provided
to the driver
Does the weight of theasbestos exceed:- Blue or brown - 333 kg?
- White - 1000 kg?

Are the packages ofasbestos to be carried ina vehicle or in a bulk
container on a vehicle?

YES

NO
Bulk container

Transport as per
timetable on the
Waste Consignment Note

- Vehicle to display
orange panel at front
and rear- Hazard placards to be
displayed on all four sidesof the bulk container

VehicleVehicle to display
orange panelat front and rear

Waste Consignment Note to be kept by the consignor for three years.
Other documentation to be kept by the operator for three months.
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APPENDIX 7.3: ASBESTOS WASTE ‘INSTRUCTIONS IN WAITING’ (TREMCARD)INFORMATION
The following information should be provided by the consignor (contractor) to the consignee (tip operator):
n
n
n
n
n
n
n
n
n

The name of the dangerous goods, ie white, blue or brown asbestos.
The class of dangerous goods, ie Class 9.
The UN number, 2212, white asbestos; 2212, brown asbestos and 2590 for blue asbestos.
The packing group, Group III for blue and brown asbestos and Group II for white asbestos.
The mass or volume of goods to be carried.
The transport category, Category 2 for blue and brown asbestos and Category 3 for white asbestos.
A declaration to say that the goods are properly labelled and in a fit condition to be carried.
The names and addresses of the consignor and the consignee.
Any other information that will enable the goods to be carried safely.

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Chapter 8: Decontamination

Summarynnnnn

Failure to decontaminate properly may lead to the spread of asbestos anddelay the four-stage clearance process.
DCUs should meet the design criteria in Appendix 8.1.
The DCU should be on site before work starts and it should be the last thing toleave site.
Employees should follow the decontamination procedures shown in Figures
8.8-8.12.
The supervisor has a vital role in ensuring that procedures are followed and thatmaintenance and regular site checks are carried out.

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Contents
Introduction

158

The decontamination process

159

What does the decontamination process involve? 160
Training in decontamination procedures 163
Monitoring of the decontamination process 163
Emergency procedures 163

DCUs

163

The different types of DCU 163
Connections to services 164
Provision of information 165

Maintenance and cleaning of hygiene facilities
Inspection and cleaning 166
Maintenance 166
Thorough examination and testing 166
Record-keeping 167

Showering and laundering

166

168

Laundering of coveralls and towels 168
Laundry operators 169

Appendix 8.1: Minimum design criteria for asbestos hygiene units

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Introduction
8.1
All personnel (workers and others) who enter enclosures or designatedwork areas are likely to become contaminated with asbestos and therefore needto decontaminate themselves when they leave. The purpose of decontamination
is to ensure that the workers clean themselves and their PPE and RPE to preventthe spread of asbestos outside the enclosure. In addition, the decontamination
procedure is designed to ensure that cleaning is performed in such a way thatit does not lead to secondary exposure for the worker. This chapter describes
the decontamination procedures that should be carried out every time workers
leave the enclosure. The chapter also specifies the enclosure entry procedures forworkers and it describes the arrangements for laundering towels and coveralls.
8.2

Decontamination consists of three stages:

Stage 1: Prevent or minimise contamination inside the enclosure, ie avoid becoming

contaminated. Prevention is the most effective action. Its importance cannot be
over-emphasised. Work should be carried out in such a way that minimal dust anddebris are produced. This will not only minimise the extent of contamination on PPE
and RPE, it will also reduce exposure and the spread of asbestos.
Stage 2: Preliminary decontamination within the enclosure and airlocks. The bulk ofcontamination should be removed from PPE and RPE at this stage.
Stage 3: Final decontamination within the DCU. The remaining residual

contamination is removed and workers change back into domestic clothing.
This three-stage structured approach to decontamination allows the process to be
conducted systematically and consistently. Workers should follow the same seriesof steps every time they leave the enclosure.

Figure 8.1 General layout of a hygiene unit

Showers

Clean end
Well sealed self-closing door
Grill with self-closing flap
Extract ventilation unit
Dirty end

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8.3
The main decontamination facility (referred to as a hygiene unit or DCU)
is a fundamental component in the worker cleaning process. The DCU can be amobile, fixed or modular facility. It allows workers to prepare for work (by changing
from their domestic clothing into their PPE and RPE) and it provides the facilities tocarry out the final stage of decontamination after exiting the enclosure. The designand specification of hygiene units are extremely important. Hygiene units must meetthe minimum design criteria and specification set out in Appendix 8.1. Figure 8.1
shows the layout of a typical hygiene unit.

The decontamination process
8.4
The provision of hygiene units is essential for licensed asbestos work.
Arrangements should be made to ensure that the DCU is on site and functioningat the very start of the job. It should be available on site for pre-clean work andfor situations where scaffolding erection is liable to disturb asbestos, and it should
be available before the enclosure is built. The hygiene unit should arrive on siteclean, even if its most recent use has been on a non-asbestos job. The unit should
contain a copy of the clearance certificate from the most recent asbestos removal
job. The certificate should be attached in a prominent position in the clean end.

Figure 8.2 Hygiene unit directly attached to the enclosure

Vacuum all PPE at the edge of the enclosure
Airlock
Wash footwear and sponge RPEIntervening space or tunnel

Dirty end
Showers

Clean end

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8.5
The purpose of going through decontamination procedures is to ensure thatany asbestos fibres or debris are removed from the person and their PPE and RPE
to prevent the spread of contamination outside the work areas. Decontamination
to prevent the spread of fibres is important not only for the asbestos removal
workers, but also for others who come into contact with them, eg their families orother workers in the vicinity of the enclosure. Family members can be exposed toasbestos if contaminated clothing is taken home.

Effective and thorough decontamination is important for asbestos
removal workers, their families and others on the site
What does the decontamination process involve?
8.6
The exact entry and decontamination procedures will depend on the layoutof the site and, in particular, on whether the hygiene unit is directly attached tothe enclosure (described as ‘non-transiting’) or is remote from the enclosure(‘transiting’). The procedures are covered in paragraphs 8.8-8.11 and 8.12-8.17
respectively. The former arrangement (ie a hygiene unit directly attached to theenclosure) is desirable and preferable as it reduces the potential for asbestos tospread outside the enclosure, and the decontamination procedures are much
simpler and shorter. Transiting should only be employed where it is not reasonably
practicable to attach the unit to the enclosure.		
8.7
The decontamination procedures are set out in five flow charts (Figures
8.8-8.12). These describe the respective enclosure entry and exit procedures
for non-transiting and transiting, as well as the procedures for washing anddecontaminating inside the DCU.
The flow charts are as follows:
n
n
n
n
n

Figure 8.8: Decontamination process: Hygiene unit attached to the enclosure:Entering enclosure
Figure 8.9: Decontamination process: Hygiene unit attached to the enclosure:
Leaving enclosure
Figure 8.10: Decontamination process: Transiting procedure: Entering enclosure
with new work coveralls
Figure 8.11: Decontamination process: Transiting procedure: Entering enclosure
after break
Figure 8.12: Decontamination process: Transiting procedure: Leaving enclosure

Hygiene unit connected to enclosure
8.8
The hygiene unit is attached to the enclosure. This type of decontamination
procedure is outlined in Figures 8.8 and 8.9. The positioning of the hygiene unit
should be considered when first assessing the job and drawing up a suitable
method statement.
8.9
The hygiene unit (mobile or modular) should be connected to the enclosure
through a short intervening space or tunnel and a one-stage airlock constructed ofpolythene sheeting (see Figure 8.2). DCUs should never be directly attached to theenclosure without the intervening space as research suggests that contaminated
air may be drawn in from the enclosure into the dirty end of the DCU (see the
HSL report Investigation into the effectiveness of modular hygiene units).35 The
intervening space is there to provide an air gap between the enclosure and the
DCU and it must be fitted with a vent to the open air. The vent openings should beconstructed in a similar manner to the enclosures’ access openings (ie slits withweighted flaps, see Figure 8.2) but should be smaller as they must not be used forentry or exit.

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8.10 This method of linking the DCU to the enclosure should be normal practiceunless it is impracticable to do so, eg due to limited space, restricted access or
multi-storey work. Transiting procedures should be avoided where possible as
there is a risk of spreading contamination along the transit route. The transit route
will form part of the four-stage clearance test at the end of the job (see paragraph7.102 on clearance procedures).
8.11 Waste should never be taken through the DCU as it could lead to grosscontamination within the unit. Waste (and equipment) should be removed from theenclosure through a separate baglock (see Box 7.5).

Enclosures should always be directly connected to the enclosure,unless this is not reasonably practicableHygiene unit remote from the enclosure
8.12 Where it is not possible to attach the DCU directly to the enclosure,transiting arrangements will have to be employed. These procedures are longer
and more complex than non-transiting. They involve the use of ‘transiting’ PPE andadditional facilities to enable the worker to carry out preliminary decontamination
before travelling to the DCU for full decontamination. The process is described in
Figures 8.10-8.12.
Figure 8.3 Transit facilities (ie three-stage airlock)Three-stage
airlock

Outer stage
Middle stage
Inner stage

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8.13 Transit facilities (also known as the three-stage airlock) should be speciallyconstructed and made of polythene sheeting. They should be attached to thestripping enclosure and should comprise of three compartments separated byweighted sheets to minimise the spread of dust between the compartments.
As shown in Figure 8.3, the inner stage is the compartment nearest to theenclosure, the middle stage is the middle compartment and outer stage is the lastcompartment that operatives will go through before walking to the DCU. The threestage airlock should be as big as possible to enable the workers to change anddecontaminate. The absolute minimum dimensions for each compartment shouldbe 1 m x 1 m x 2 m. Where space is unrestricted, these compartments should belarger.

Airlocks should have minimum internal dimensions for eachcompartment of 1 m (width) x 1 m (depth) x 2 m (height)
8.14

The three stages should have the following facilities within them:

Outer stage: Facilities to store transit overalls and footwear, eg hooks and/or shoeholders.
Middle stage: Facilities to store overalls and footwear worn in the enclosure, eg hooks
and/or shoe-holders.

Inner stage: Footbath and brush, water bucket and sponge or wipes for RPE.
(Type H vacuum cleaner is usually located at the edge of the enclosure).
8.15 The transit procedure is designed to ensure that the potential for spread ofasbestos fibres from ‘used’ work PPE during transiting is minimised. On leaving
the enclosure, all contaminated items (ie coveralls, footwear and RPE) should
be cleaned, and coveralls and footwear should be replaced or covered. Transit
coveralls (normally a distinct and different colour to work coveralls) and footwear
should be worn travelling to and returning from the enclosure. Used work coveralls
should be removed in the middle stage of the airlock and either disposed of as
hazardous waste or stored for reuse, eg after meal breaks. Used work footwear
may be stored after use (in the middle stage) or covered with ‘overshoes’ duringtransiting. New (ie unused and clean) work coveralls should be worn undertransiting coveralls en route to the enclosure.
8.16 All transit routes should be delineated to ensure that other workers
or members of the public keep away from this route, where practicable. Any
contamination found on the transit route at clearance stage will delay the issuing ofa certificate of reoccupation to the client.
8.17 In a few exceptional circumstances the normal travelling procedures
described above may not be appropriate. There may be some circumstanceswhere wearing a full-facepiece respirator causes increased health and safety risks
such as trips and falls, eg if transiting at height or through heavy industrial plant.
This type of situation is foreseeable and alternative arrangements can be put into
place. In such circumstances, the full-facepiece respirator may be removed in the
middle stage of the transit facility after primary decontamination and replaced witha FFP3 disposable face mask. The worker can then travel to the DCU wearing thedisposable mask and carrying the full-facepiece respirator.

The relevant decontamination procedure should be followed eachtime a worker leaves the enclosure

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Figure 8.4 Mobile facilities

Training in decontamination procedures
8.18 Chapter 4 on training specifies the topics that must be covered byasbestos removal operatives. It is essential that workers receive practical training
on decontamination procedures to acquire the knowledge and skills necessary to
decontaminate properly. Training should involve practising how to decontaminate
in a simulated environment. It is particularly important for workers to recognise theneed for primary decontamination during transit procedures.
Monitoring of the decontamination process
8.19 Supervisors play a key role in the day-to-day monitoring and checkingof all procedures, including decontamination. It is essential that operatives
decontaminate thoroughly each time that they leave the work area, no matter how
short the time spent inside the enclosure. Supervisors should monitor compliancewith decontamination procedures (frequency and duration) to ensure that workers
do not develop poor practices or become complacent. In addition, supervisors
should ensure that no inappropriate items are taken into the hygiene unit, eg filledwaste bags, lemonade bottles etc.

Figure 8.5 Modular facilities

Final decontamination should be carried out, irrespective of the timespent inside the enclosure
8.20 Where operatives are found not following the decontamination procedures,consider retraining and/or the instigation of internal disciplinary procedures.
Incomplete or ineffective decontamination is a very serious matter and may cause
asbestos exposure for the individual, colleagues, other workers and even family
members (see paragraph 8.5).
Emergency procedures
8.21 Arrangements should be made for suitable emergency procedures to be
implemented in the event of loss of services to the DCU. Contingency plans should
be developed for alternative basic decontamination procedures using other facilities
on site or by organising the services of another DCU. These arrangements should
be clearly formulated so that workers and supervisors are aware of the actions totake.

Figure 8.6 Vehicle type

DCUs
The different types of DCU
8.22 There are various types of DCUs used by contractors. The common
types are ‘mobile’ and ‘modular’ facilities (see Figures 8.4 and 8.5 respectively).
In addition ‘vehicle type’ DCUs have been developed in recent years and are
becoming more popular, particularly on short-duration jobs (eg soffit removal) andon sites where security is an issue (see Figure 8.6). Historically, other types of DCUs
have also been used (eg ‘fixed’ types such as converted welfare facilities). The
minimum design criteria for different types of unit are given in Appendix 8.1.
8.23 Hygiene units should be purpose-built and should only be used for thedecontamination of asbestos workers. Additional welfare facilities such as toilets
and canteen facilities will be required to satisfy regulation 22 of the Construction(Health, Safety and Welfare) Regulations 199636 (see also Provision of welfare
facilities at fixed construction sites).37 Hygiene units should not be used as general
welfare facilities.

It is unlikely that a converted caravan or construction site welfare
hut would be capable of meeting the design criteria listed inAppendix 8.1
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Mobile units
8.24 For the purposes of this guidance, a mobile unit is a caravan-style or
re-locatable self-contained unit that can be towed to the site. This type of unit
should be used in preference to modular units, as they are generally larger andtherefore provide more space and comfort for thorough decontamination. They areusually available in several sizes to accommodate 2-8 people.
Modular units
8.25 Modular hygiene units are panel-based systems which enable rapid
construction of the facilities on site. The panels reduce the space required forstorage and transportation. Some modular units can be assembled in different
configurations (eg straight line or L-shape) or be extended to more than threecompartments. The air extraction unit, the water management system and theelectrical/sockets system are usually positioned outside the hygiene facility.
8.26 The use of such units can avoid the need for transiting and mean that thefacility can be attached to the enclosure (via an intervening space, see paragraph8.9). There are potential disadvantages with modular units, particularly size,
integrity, and the effectiveness of the water management systems. Any modular
units that do not meet the criteria in Appendix 8.1 should not be used for asbestos
removal decontamination work.
Vehicle units
8.27 This is a relatively new design of unit. It is a self-contained, fully independent
unit that can be driven directly to the site. Its mobility and flexibility offer benefits forcertain jobs and situations, eg short duration jobs (soffits) and sites where security
is an issue. The vehicle is usually designed to contain a storage section as well as
the DCU. Size may be an issue for this type of unit. It should meet the criteria in
Appendix 8.1.

The reasons for using modular units should be clearly set out in the
RA and method statement for the job
Connections to services
Electrical services
8.28 For the purpose of specifying the electrical systems, a DCU should betreated in the same way as a caravan. The applicable technical standard for the
power distribution system in the unit is BS 7671:2001,38 with Section 608
Division 1 providing specific requirements relating to installations in caravan-likestructures such as a DCU, and with Section 601 being applicable to the electricalsystems in the shower area of the DCU.
8.29 The supplies to the DCU may be drawn from a fixed installation or from agenerator and will typically be single phase 230 volts. Units may operate at 110
volts, commonly supplied from a transformer with its secondary windings centretapped to earth, although there is no specific requirement for the use of reduced
extra low voltage supplies in this particular application. If the intention is to supply
the DCU from a generator provided by the user, it will be necessary to check thatthe voltage, power rating, earthing and referencing, overcurrent and earth fault
protection, isolation, and emergency stop features are suitable and appropriate forthe application. If the generator is on hire, the hirer should provide full instructions
on the safe use of the generator.
8.30 The electrical supply to the unit should be configured as a TN-S or TT
system, as defined in BS 7671:2001,38 and should not be TN-C-S (also known as
combined neutral/earth or protective multiple earthing).

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8.31 Protection against indirect contact electrical injury should normally beprovided by earthed equipotential bonding and automatic disconnection of supply.
In addition to protection against excess current, the installation should have aresidual current protective device, such as an RCD, fitted in the main consumer
unit or distribution board. The rated residual operating current of the device should
not exceed 30 milliamps and the device should trip within 40 milliseconds for aresidual current of 150 millamps. In those circumstances where the residual current
device is on the supply to lighting circuits, consideration should be given to fitting
emergency lighting in the unit to provide illumination in the event of the supply
tripping.
8.32 Before first use, the electrical systems should be inspected and tested by
a competent person to verify compliance with the standards. The requirements
for initial verification of the power distribution systems are described in Section
2 of the Institution of Electrical Engineers (IEE) guidance note Inspection andTesting.39 Electrical equipment used in the DCU should be inspected and tested
in accordance with the guidance in the IEE’s Code of Practice for In-service
Inspection and Testing of Electrical Equipment.40
8.33 When delivered to site, checks should be made to ensure that the power
supply is compatible with the DCU. If the intention is to use a power socket outlet
in the user’s premises, the earthing configuration and the voltage, polarity and earth
fault loop impedance at the socket outlet should be checked to ensure that they
are suitable for the application. This will normally need to be done by a competentperson with specialised skills and knowledge, such as an electrician.
Gas appliances
8.34 The gas (normally liquid petroleum gas (LPG)) system needs to be checked
to ensure that it is operating safely. The gas pipework connections and boiler canbe damaged during transportation and use. Therefore, the LPG system and boiler
should be inspected daily and at the end of a contract (hire) and before the next
use of the DCU.
Water supply and wastewater
8.35 Ensure that the water and wastewater supplies are insulated against frost
damage. All piping should have flexible jointing to prevent rupture. Wastewater
should be filtered through a high efficiency filter (specification less than 5 microns).
It is essential to check that there is sufficient water pressure and hot water.
Figure 8.7 Notices on DCU

Provision of information
8.36 Notices on and in the hygiene unit can prevent misunderstanding andcontinually warn people of hazards. Notices should be fixed at each entrance
door, clearly indicating which is the clean and which is the dirty end and prohibiting
unauthorised entry (see Figure 8.7). Drainage pipes and electrical connections
should be labelled.

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Maintenance and cleaning of hygiene facilities
Inspection and cleaning
8.37 Debris should not be allowed to accumulate and enclosure waste bags
should never be allowed to pass through the DCU. Hygiene facilities should becleaned at the end of each working day. This should include vacuuming and athorough washing down of all exposed surfaces. The filled waste bags in theshower and dirty end should be removed (stocks of waste bags and NPU prefilters should be retained in the shower compartment and dirty end, as appropriate).
People carrying out cleaning should wear protective clothing and RPE and should
work from the clean end towards the dirty end. Waste bags from the shower anddirty end (properly cleaned, labelled and double bagged) should be removed via thedirty end.
8.38 Before leaving the site, the water systems should be drained, traps in theshower and washbasin waste should be emptied and residues placed in a plastic
bag for disposal as asbestos waste. Any transit route and the area where thefacility has been parked should be inspected and cleaned as necessary, to ensurethat there is no residual asbestos waste.
8.39 At the end of the asbestos job, the hygiene facility should be thoroughly
cleaned and then subjected to a clearance test. Full details on this are given
in paragraphs 7.146-7.148. On successful completion of the test, a clearance
certificate should be posted in the clean end of the unit before it is used for the
next job. Where the DCU is removed from site at the end of the working day forsecurity reasons, it should be locked and treated as being contaminated. It should
be returned to as close to the previous location as possible.
Maintenance8.40 The DCU should be kept in an efficient state, efficient working order and ingood repair. A list of daily and weekly checks, to be carried out by a supervisor,
can be found in Box 8.1. In addition, the unit should be maintained in accordancewith the manufacturer’s instructions. If there are problems with any of the following:
shower, heating, extraction and battery-charging facilities, the unit should not be
used until a replacement item has been made available, or the fault has been
remedied.

If there are problems with the shower, heating, extraction or
battery-charging facilities, the unit should not be used
Thorough examination and testing
8.41 The following equipment should be examined and tested by a competentperson and a record kept:nnn

Air extraction system (every six months): including DOP or sodium chloride
tests on the HEPA filter and a check on the volumetric flow rates.
Gas appliances: should be serviced and maintained in accordance with the
manufacturer’s recommendations. Gas fitters should be competent and havereceived training accredited by UKAS.
Electrical systems: Electrical systems in the DCU should be maintained inaccordance with the IEE guidance note39 on Inspection and Testing (for the
distribution system) and the IEE’s Code of Practice for In-service Inspection andTesting of Electrical Equipment40 (for the electrical equipment including portableappliances).

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n

n

n

n

n

Electrical systems should be routinely checked. Checks should include:– a visual inspection for evidence of breakages, wear/deterioration, signs ofoverheating, missing parts (eg screws, covers), switchgear accessible (ie notobstructed), secure doors, adequate labelling, loose fittings;– operation of the equipment, ie equipment is working: lighting, heating,shower unit, RCDs (using test button), sockets, switchgear (where
reasonable).
The routine checks should be undertaken by a competent person on a
weekly basis and a formal recorded check should be made monthly. The
RCDs providing automatic disconnection on the distribution circuits should betested on a daily basis. The routine checks should embrace all the electricalequipment in the DCU. The competent person selected to do this work does
not need to be an electrician but should be someone who has been trainedon what to look for and who can be relied upon to do the job in a thoroughmanner.
Electrical equipped (including portable equipment) installed or used in the
DCU should also be inspected and tested in accordance with the IEE Code ofPractice.40 The in-service combined inspection and test should be performed
before the DCU is delivered to site. For the power distribution system the tests
should include a combination of continuity, insulation resistance and functional
tests as described in the IEE guidance note.39
When the DCU remains on site or in continual use for extended periods,
subsequent combined inspection and tests should be carried out every threemonths in line with the requirements for installations on construction sites.38
The tests do not need to be as extensive as the initial test but should include
continuity (of the circuit protective conductors, and the main supplementarybonding connections), earth fault loop impedance tests, and functional tests.
Combined inspection and testing should be undertaken by a competent person(normally a qualified electrician for work on the power distribution system).

Record-keeping
8.42 Records should be kept of site inspections as well as thoroughexaminations and tests. Thorough examination and test records should be kept forfive years and copies of the most recent tests should be available for inspection onsite.

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Box 8.1 Supervisors’ checklist for asbestos hygiene units
Pre-use checks

Visual check of electrical equipment for obvious defects:■■ compatibility of electrical power sources;■■ an earth fault loop impedance test;■■ the voltage and plug pins of electrical equipment are compatible;■■ when modular hygiene units are installed on site the earth bonding should bechecked.
Daily checks

The following daily operational checks should be carried out by a suitably trained
supervisor before the beginning of each shift:■■ adequate supplies of water, gas and electricity;■■ adequate shower pressure and temperature;■■ operation of heating system;■■ operation of NPU, including checking the pressure gauge/warning device toensure that the HEPA filter has not become saturated;■■ functioning battery chargers;■■ provision of sufficient waste bags, towels (one set in the shower area and one

in the ‘clean’ end), filters and PPE;■■ cleanliness of unit and transit route and facilities;■■ operation of vacuum cleaner; supply of sponges and water baths in any transit

airlock provided;■■ the integrity of airlocks;■■ environmental conditions that may affect the use of the DCU facilities, eg frozen

pipes;■■ testing of RCDs.
Weekly checks

Visual check of electrical equipment for damage, wear, overheating etc.

Showering and laundering
Laundering of coveralls and towels
Coveralls
8.43 Coveralls used during asbestos work should be treated as contaminatedand therefore must either be disposed of as asbestos waste, or bagged up for
washing at a ‘specialist’ laundry, ie a laundry which has the facilities and expertiseto launder asbestos-contaminated items. Contaminated coveralls must never betaken home.
Towels8.44 HSE research has demonstrated that there is the potential for towels usedby asbestos workers to become contaminated (Investigation into the effective
laundering of towels and coveralls used for asbestos work).41 The contaminationof the towels suggests that workers or their RPE are not being fully or effectively
decontaminated, or that towels have been used to clean surfaces.
8.45 Contaminated towels have the potential to cause further spread andexposure and therefore there are implications for subsequent towel handling andlaundering. Procedures for laundries which handle asbestos-contaminated items
are set out in paragraph 8.47. In addition, asbestos contractors must have a policy
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and procedures for towel use. Guidance on this is set out in Box 8.2. Contractors
must however ensure that their workers carry out full and effective decontamination(including their RPE) in the shower every time.

Never take home towels used beyond the clean end of thehygiene facility
8.46 Contaminated towels should be bagged and laundered separately fromcontaminated coveralls.
Laundry operators
8.47 Laundry operators (ie independent specialist commercial laundries and‘in-house’ laundries operated by asbestos removal companies) should assess thepotential risks from laundering asbestos-contaminated clothing and towels (bothbefore and after laundering) and, to prevent exposure and spread of asbestos,should:
n
n
n
n
n
n
n
n
n
n

provide a clearly defined, lockable room(s) containing the washing and drying
machines dedicated for dealing with asbestos-contaminated laundry only;
limit access to these facilities to a minimum number of trained and equipped
personnel;
provide good mechanical air extraction (negative pressure with HEPA filtration)in the room(s);equip employees loading the washing machine(s) with appropriate RPE;
operate high standards of hygiene;
use separate wash cycles for heavily and lightly contaminated items;
use separate wash cycles for towels and coveralls;
filter waste water and subsequently treat the filter(s) as contaminated asbestos
waste;
discharge air from tumble drier(s) to the external atmosphere;
conduct regular air monitoring and record the results.

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Box 8.2 Showering procedures and the use of towels
On returning to the DCU, all workers should shower thoroughly and properly bytaking sufficient time (a minimum of five minutes), care and attention. In particular,
hair should be thoroughly washed and fingernails should be thoroughly scrubbed.
After thorough decontamination in the shower cubicle, the next step is to ensurethat employees follow the company’s system for the use of towels for drying.
There are two options which employers can use:■■ drying in the shower cubicle;■■ drying in the clean end of the DCU.

Employers must decide which of these options to use – they cannot mix
both. Irrespective of which option is used, employers need to ensure that theiremployees follow the system by instructing them in the procedures, monitoring
their compliance and by taking remedial action as necessary.
Drying in the shower cubicle

Having thoroughly showered, employees should:■■ dry themselves as thoroughly as possible while still in the shower cubicle,

including their feet and toes;■■ treat the towel used in the shower cubicle as contaminated and either disposeof it as asbestos waste or bag it up for washing at the specialist laundry;■■ if necessary, finish off drying in the clean end of the DCU, using a fresh towel,

which if it has never progressed beyond the clean end of the DCU, can be 		
deemed to be uncontaminated.
Drying in the clean end of the DCU only

Having thoroughly showered, employees should:■■ step into the clean end of the DCU and using a clean towel (ie one that has

never progressed beyond the clean end), carry out the entire drying process
there;■■ treat the towel as uncontaminated and either dispose of it as non-asbestos
waste or bag it up for washing with normal laundry (taking care not to crosscontaminate with any asbestos-contaminated laundry), using the employer’s
systems.
Employers using the second option will need a system to test that towels
used solely in the clean end of the DCU have not become contaminated. It issuggested that periodic testing (eg 5% of jobs) is carried out, using a suitable
method, to check for asbestos contamination on towels. The findings should berecorded.

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APPENDIX 8.1: MINIMUM DESIGN CRITERIA FOR ASBESTOS HYGIENE UNITS
A8.1.1 The criteria listed below apply to mobile and modular units, unless otherwise stated. Mobile units offer
more space to decontaminate properly. A modular unit should only be used where space does not permit theuse of a mobile unit and where its use removes the need for transit procedures. The same design criteria should
also be used in the construction of vehicle-type hygiene units.

If a DCU is used that does not meet these criteria, enforcing authority inspectors may
consider the unit to be unsuitable for asbestos decontamination and prohibit its use
A8.1.2 The following criteria for hygiene units have been compiled after consultation with known suppliers andmanufacturers of hygiene units. The list also incorporates recommendations from a Health and Safety Laboratory
report, Investigation into the effectiveness of modular hygiene units,35 which examined the standards for modular
hygiene units.
Design and general construction
A8.1.3 Hygiene units should:
n
n
n
n
n
n

n
n
n

n

be weatherproof or only be used inside a weatherproof building;be able to be made level on uneven ground;be robust enough not to distort when moved (racks are available for the storage of modular unit panels);
have robust fixings that are not easily damaged in transport or use or dismantling (wing nuts and clips havebeen found to become easily damaged);
be roadworthy (see National Trailer Towing Association guidance for trailed units);
be of adequate size. Modular units should have minimum internal dimensions for each compartment of 1
m x 1 m x 2 m (height). Modular units should only be used by a maximum of two people at any one time.
Mobile units are expected to be larger than modular units;
have self-closing doors which should separate the three compartments (‘clean’, shower and ‘dirty’);
have outward opening doors on the external access to the ‘clean’ and ‘dirty’ ends (self-closing at ‘dirty’end);have internal surfaces that are impervious. Ledges and grooves should be avoided. The installation of
windows should be avoided, but any windows provided should be non-opening, unbreakable and fitted flushwith the inner wall. Units should be capable of being cleaned on site so that a clearance certificate can beissued showing the next user that the unit has been cleaned;
be capable of being locked when not in use.

Heating and lightingn Heating should be provided and heating appliances should be easy to clean.
n Units designed to be used inside buildings should be fitted with electrical water heating systems to avoid theneed to vent combustion gases from gas appliances to the open air.
n Where gas appliances are fitted they should meet BS EN 1949:2002.42 All gas appliances should be installedby competent gas fitters who have received relevant training from a training body accredited by UKAS.
n LPG cylinders should be stored and transported in an external ventilated cupboard or rack that can bereadily secured.
n Only room-sealed balanced flue-type gas heating appliances should be used.
n Adequate artificial lighting should provide, eg between 100-200 lux.
n Light fittings and other electrical appliances should be easy to clean and double insulated or permanently
wired into the circuit and switched.
Servicesn The electrical system should have earth bonding and an earth leakage circuit breaker.
n All electrical equipment should meet BS 7671:200138 and BS 6767:1998, Part 2.43
n Connections to the water supply should have flexible joints. The supply should be protected against frost.
n Water filtration: wastewater should be filtered through a high efficiency filter (specification less than 5
microns).
n Hot water systems should be designed to avoid ‘dead-legs’, where legionella bacteria could grow.

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Ventilationn The unit should be ventilated. Air should be drawn in at the ‘clean’ end, pass through the shower and be
discharged at the ‘dirty’ end (ie the NPU should be located in the ‘dirty’ end). A minimum of 30 air changes
per hour should be achieved in the ‘dirty’ end.
n Grilles should be a minimum of 15 cm x 30 cm and pressure/gravity-operated flaps a minimum of 20 cm x
23 cm. However, it is the overall area of the grilles that affects the airflow, unless the louvres are at such asevere angle that they create turbulence. Better airflow will be achieved by having grilles on either side of theinterior walls and by alternating from high to low level. External vents should be located as near to a central
position as possible or have two symmetrical intakes. They should be provided with dust caps for transit.
n Air should be discharged via a HEPA filter or absolute filter and via a pre-filter.
n The extraction point should be placed low down in the ‘dirty’ end (or placed externally on modular units), butleaving enough room to clean beneath it, and positioned so that cleaning water does not damage it.
n A visible or audible warning device (such as a pressure gauge or warning light) should alert users to a failureof the NPU.
Facilities within compartments
n Lockers should only be used as seats in modular units where they are not in a position to block vents andair extraction points. Bench-type seating is preferred in addition to lockers.
n Showers: curtains should not be provided but a curtain rail should be provided above each shower on which
to hang the operative’s RPE battery pack etc while showering. One shower should be provided per four
people. Hooks should be provided to hang up towels. Water pressure and flow should be regulated so thatpressure does not drop when pumping water out of the unit or while using the wash-hand basin at the sametime as one of the showers. The shower should have a thermostat, a shower rose, an outlet to the drain, aholder for soap or shower gel (use of gel helps to prevent the wastewater filter getting blocked), shampoo
and nail brush etc and preferably have a shower tray.
n The ‘clean’ end: at least four hooks should be provided for hanging up clothing etc as well as a locker foreach operative to store valuables. Battery-charging facilities (unless provided separately with a modular unit),a mirror and fixed seating (see first bullet point above) will be required. The ‘clean end’ needs to have themost space available for storage and dressing and undressing. Units can be designed to add on an extra
unit or suitable changing area at this point to extend the facilities.
n The ‘dirty’ end: at least four hooks to hang RPE belts from while workers remove work or transit clothing
and to hang up work or transit clothing. Sufficient space will be required to hold bagged waste filters etc.
Fixed bench-type seating should be provided (see first bullet point above). A suitable wash-hand basin withplug and drainage point should be provided in either the shower area or ‘dirty’ end of the unit for washingdirty hands.
Maintenancen All units should be maintained in ‘an efficient state, in efficient working order and in good repair’. Hirers andusers should be prepared to demonstrate how they maintain their equipment. Manufacturers and suppliers
should provide information to buyers about how to maintain their units.
Informationn Notices: to indicate the ‘clean’ and ‘dirty’ ends and that unauthorised entry is prohibited. All drain outlets
and electrical connections should be labelled to identify them.

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Figure 8.8 Decontamination process: Hygiene unit attached to enclosure: Entering enclosure

Entering enclosure
Take RPE/PPE/toiletries into hygiene unit via clean end door

Inspect and check RPE.
Undress

Put on clean PPE. Put on RPE using mirror.
Carry out fit check

Pass through shower area (without showering and leaving toiletries)
into the dirty end

Leave hygiene unit. Go through interim space andairlock into enclosure

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Figure 8.9 Decontamination process: Hygiene unit attached to enclosure: Leaving enclosure

Leaving enclosure
Vacuum all visible dust and fibres from PPE, RPE and footwear at the edgeof the enclosure. Leave enclosure and enter airlock

Brush footwear in footbath. Sponge or wipe RPEEnter dirty end of hygiene unit. Take off all footwear, coveralls and underwear
worn in the enclosure and place in storage or disposal bags. Do not remove RPE

Move to shower area with respirator on. Shower and use a sponge to clean
RPE without allowing water onto filter ports

Once RPE has been cleaned, remove it and shower yourself thoroughly.
Remove or cap used filters (place in waste bag for disposal if appropriate)

Start drying off. Place towel in bag for disposal or laundering

Pass through into clean end carrying RPE and complete drying
with a different towel(s). DressLeave hygiene facility via clean end external door

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Figure 8.10 Decontamination process: Transiting procedure: Entering enclosure withnew work coveralls

Entering enclosure
Take RPE into hygiene unit via clean end door

Inspect and check RPE.
Undress

Put on clean PPE. Put on RPE using mirror.
Carry out fit check

Pass through shower area (without showering) into the dirty end.
Dress in transit coveralls and footwear

Pass through door of dirty end and walk to transit facilities via
designated transit routeEnter outer stage of transit airlock and remove transit coveralls andfootwear, place in container/on hooks provided. Do not leave on the floor

Pass into middle stage of transit airlock.

Pass through the inner stage and into the enclosure

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Figure 8.11 Decontamination process: Transiting procedure: Entering enclosure after breakEntering enclosure
Take RPE into hygiene unit via clean end door

Inspect and check RPE.
Undress

Put on clean undergarments. Put on RPE using mirror.
Carry out fit check

Pass through shower area (without showering) into the dirty end.
Dress in transit coveralls and footwear

Pass through door of dirty end and walk to transit facilities via
designated transit routeEnter outer stage of transit airlock and remove transit coveralls andfootwear, place in container/on hooks provided. Do not leave on the floor

Pass into middle stage of transit airlock.

Pass through the inner stage and into the enclosure

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Figure 8.12 Decontamination process: Transiting procedure: Leaving enclosure

Leaving enclosure
Vacuum all visible dust and fibres from PPE, RPE and footwear at the edgeof the enclosure. Leave enclosure and go into inner stage of transit airlock.
Brush footwear in footbath. Sponge down or wipe RPE

Pass into middle stage of airlock. Remove coveralls and footwear worn inenclosure and place in waste bag (or store if re-entry required). Do not remove RPE

Pass into outer stage. Put on transit overalls and transit footwear.
Walk to hygiene facility via designated transit routeEnter dirty end of hygiene facility. Take off all footwear, PPE and underwear
and place in storage or disposal bags. Do not remove RPE

Move to shower area with respirator on.
Shower and use a sponge to clean RPE

Once RPE has been cleaned, remove it and shower yourself thoroughly.
Remove or cap used filters (place in waste bag for disposal, if appropriate)

Start drying off.
Place towel in bag for disposal or laundering

Pass through into clean end carrying RPE and complete drying
with different towel(s). DressLeave hygiene facility via clean end external door

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References and further
information
1
Asbestos (Licensing) Regulations 1983 SI 1983/1649 The Stationery Office
1983 ISBN 0 11 037649 8 as amended by the Asbestos (Licensing) (Amendment)
Regulations 1998 SI 1998/3233 The Stationery Office 1998 ISBN 0 11 080279 92Asbestos essentials task manual: Task guidance sheets for the building
maintenance and allied trades HSG210 HSE Books 2001 ISBN 0 7176 1887 03Working with asbestos cement HSG189/2 HSE Books 1999 ISBN 0 7176
1667 3
4
Safety Representatives and Safety Committees Regulations 1977 SI
1977/500
The Stationery Office 1977 ISBN 0 11 070500 9
5Health and Safety (Consultation with Employees) Regulations 1996 SI
1996/1513 The Stationery Office 1996 ISBN 0 11 054839 66Consulting employees on health and safety: A guide to the law Leaflet
INDG232 HSE Books 1996 (single copy free or priced packs of 15 ISBN 0 7176
1615 0)7
Control of Asbestos at Work Regulations 2002 SI 2002/2675 The Stationery
Office 2002 ISBN 0 11 042918 48Asbestos: The analysts’ guide for sampling, analysis and clearance
procedures HSG248 HSE Books 2005 ISBN 0 7176 2875 2
9Health and Safety at Work etc Act 1974 (c 37) The Stationery Office 1974
ISBN 0 10 543774 3
10Management of health and safety at work. Management of Health and
Safety at Work Regulations 1999. Approved Code of Practice and guidance L21(Second edition) HSE Books 2000 ISBN 0 7176 2488 9
11Managing health and safety in construction: Construction (Design andManagement) Regulations 1994. Approved Code of Practice and guidance
HSG224 HSE Books 2001 ISBN 0 7176 2139 1
12Work with asbestos insulation, asbestos coating and asbestos insulatingboard. Control of Asbestos at Work Regulations 2002. Approved Code of Practiceand guidance L28 (Fourth edition) HSE Books 2002 ISBN 0 7176 2563 X
13Introduction to asbestos essentials: Comprehensive guidance on working
with asbestos in the building maintenance and allied trades HSG213 HSE Books
2001 ISBN 0 7176 1901 X
14
A comprehensive guide to managing asbestos in premises HSG227 HSE
Books 2002 ISBN 0 7176 2381 5
15
Safe work in confined spaces. Confined Spaces Regulations 1997.
Approved Code of Practice, Regulations and guidance L101 HSE Books 1997
ISBN 0 7176 1405 0
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16
Control of substances hazardous to health (Fifth edition). The Control of
Substances Hazardous to Health Regulations 2002 (as amended). Approved Codeof Practice and guidance L5 (Fifth edition) HSE Books 2005 ISBN 0 7176 2981 3
17
Final report on the development of practical guidelines for the training ofasbestos removal workers Health and Safety Laboratory. Report for European
Commission DGV under agreement number VG/1999/5190
18
Review of training provided to asbestos removal workers 2002 Health and
Safety Laboratory. Report no WPS/02/06
19
Successful health and safety management HSG65 (Second edition) HSE
Books 1997 ISBN 0 7176 1276 7
20The Hazardous Waste (England and Wales) Regulations 2005 SI 2005/894
The Stationery Office 2005 ISBN 0 11 072685 5
21
The Special Waste Amendment (Scotland) Regulations 2004 Scottish SI
2004/112 The Stationery Office 2004 ISBN 0 11 069030 3
22
Environmental Protection Act 1990 (c 43) The Stationery Office 1990
ISBN 0 10 544390 5
23
Respiratory protective equipment at work: A practical guide HSG53 (Third
edition) HSE Books 2005 ISBN 0 7176 2904 X
24
Fit testing of respiratory protective equipment facepieces OC 282/28 HSE
2003
25
BS EN 12021:1999 Respiratory protective devices. Compressed air forbreathing apparatus British Standards Institution 1999 ISBN 0 580 32082 0
26
BS EN ISO 13982-1:2004 Protective clothing for use against solid
particulates. Performance requirements for chemical protective clothing providing
protection to the full body against airborne solid particulates (type 5 clothing) British
Standards Institution 2005 ISBN 0 580 46224 2
27
Personal protective equipment at work (Second edition). Personal Protective
Equipment at Work Regulations 1992. Guidance on Regulations 1992 (asamended) L25 (Second edition) HSE Books 2005 ISBN 0 7176 6139 3
28
General access scaffolds and ladders Construction Information SheetCIS49(rev1) HSE Books 2003
29
Tower scaffolds Construction Information Sheet CIS10(rev4) HSE Books
2005
30
Health and safety in roof work HSG33 (Second edition) HSE Books 1998
ISBN 0 7176 1425 5
31BS 5415-1:1985 Safety of electrical motor-operated industrial andcommercial cleaning appliances. Specification for general requirements British
Standards Institution 1985 ISBN 0 580 14667 7
32
Carriage of Dangerous Goods and Use of Transportable Pressure
Equipment Regulations 2004 SI 2004/568 The Stationery Office 2004 ISBN 0 11049063 0

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33
Are you involved in the carriage of dangerous goods by road or rail?
INDG234(rev) HSE Books 1999 (single copy free or priced packs of 10 ISBN 07176 1676 2)
34
BS EN ISO/IEC 17025:2005 General requirements for the competence oftesting and calibration laboratories British Standards Institution 2005 ISBN 0 580
46330 335
Investigation into the effectiveness of modular hygiene units Report
HSL/2001/16 Health and Safety Laboratory 2001
36
A guide to the Construction (Health, Safety and Welfare) Regulations 1996
Leaflet INDG220 HSE Books 1996 (single copy free or priced packs of 10 ISBN 07176 1161 2)
37
Provision of welfare facilities at fixed construction sites Construction
Information Sheet CIS18(rev1) HSE Books 199838
BS 7671:2001 Requirements for electrical installations. IEE Wiring
Regulations. Sixteenth edition British Standards Institution 2001 ISBN 0 863 41373
039
Inspection and Testing: Guidance Note 3 (for BS 7671:2001) The Institutionof Electrical Engineers 2002 ISBN 0 85296 991 0
40
Code of Practice for In-service Inspection and Testing of Electrical
Equipment (Second edition) The Institution of Electrical Engineers 2001 ISBN 085296 776 4
41Investigation into the effective laundering of towels and coveralls used forasbestos work Report HSL/2002/22 Health and Safety Laboratory 2002
42
BS EN 1949:2002 Specification for the installation of LPG systems forhabitation purposes in leisure accomodation vehicles and in other road vehicles
British Standards Institution 2002 ISBN 0 580 40404 8
43BS 6767-2:1998 Transportable accommodation units. Recommendations
for design and installation of services and fittings with guidance on transportation,
siting and aspects relating to habitation British Standards Institution 1998 ISBN 0
580 29521 4Asbestos: The licensed contractor’s guide

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Further information
For information about health and safety, or to report inconsistencies or inaccuracies
in this guidance, visit www.hse.gov.uk/. You can view HSE guidance online andorder priced publications from the website. HSE priced publications are alsoavailable from bookshops.
British Standards can be obtained in PDF or hard copy formats from
BSI: http://shop.bsigroup.com or by contacting BSI Customer Services for hardcopies only Tel: 020 8996 9001 email: cservices@bsigroup.com.
The Stationery Office publications are available from The Stationery Office,
PO Box 29, Norwich NR3 1GN Tel: 0870 600 5522 Fax: 0870 600 5533
email: customer.services@tso.co.uk Website: www.tsoshop.co.uk/ (They are alsoavailable from bookshops.) Statutory Instruments can be viewed free of charge at
www.legislation.gov.uk/.

Published by the Health and Safety Executive

07/12

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