GIBRALTAR MARITIME ADMINISTRATION(Ministry of Maritime Affairs)

Watergate House
2/8 Casemates Square
Gibraltar

Tel (+350) 200 46862 / 47771 / 50424
Fax (+350) 200 47770
e-mail: maritime.survey@gibraltar.gov.gi
maritime.registry@gibraltar.gov.gi
Maritime Labour Notice (MLN) – 018______________________________________________________________________________
To: Ship Owners, Operators, Masters, Officers and Classification Societies

MLN 4.3(B) Health and Safety – Vibration

This MLN is part of a series of MLNs which provide guidance on compliance with Gibraltar regulations
which give effect to MLC 2006 Title 4.3. Implementation of these guidelines will be taken as evidence ofcompliance with the Gibraltar regulations.
The guidelines do not preclude the ship-owner from demonstrating an equivalent or higher standard as an“alternative method” of evidence of compliance.

Documents referred to in this notice:
Maritime Labour Convention 2006 (MLC);

Gibraltar Merchant Shipping (Maritime Labour Convention) Regulations 2012. Reg. 30
Health and Safety Executive publications: Control the risks from hand-arm vibration INDG175 and Control
back-pain risks from whole-body vibration INDG242;
ILO Code of Practice; Ambient Factors in the Workplace, Geneva 2001;
Maritime and Coastguard Agency publications: Code of Practice for Controlling Risks due to Whole-bodyVibration on Ships and Code of Practice for Controlling Risks due to Hand-transmitted Vibration on Ships;
BS EN ISO 5349-1:2001 and ISO 2631-1:1997.
Most regulations and notices are available on the Gibraltar Government website; www.gibraltarship.com

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Protecting seafarers from exposure to vibration
This Maritime Labour Notice forms part of a series of MLNs for MLC Regulation 4.3 health and safety
protection and accident prevention.
MLC regulation 4.3 requires reasonable precautions are taken to reduce and prevent the risk of exposure
to harmful levels of ambient factors and chemicals on board the vessel. Harmful levels of ambient factors
include vibration and this MLN explains the Gibraltar Maritime Administration regulations and where
necessary gives guidance on how to protect seafarers from the adverse effects of vibration on board ships.
During MLC inspections the surveyor may check to ensure that a risk assessment has been carried out
and the levels of mechanical vibration on the vessel have been evaluated. Where there is evidence that
there is a risk to seafarers to the exposure from vibration or any of the exposure values have been
exceeded the surveyor will also be looking for evidence that the appropriate action as described in thisMLN has been taken.
SECTION 1
Introduction
1. Why seafarers should be protected from exposure to vibration.1 Mechanical vibration is vibration that occurs in a piece of machinery or equipment, or on a ship as aresult of its operation. Mechanical vibration can cause severe back pain and long-term damage to hands
and fingers. There are two types of mechanical vibration to be considered; hand-arm vibration and wholebody vibration.
.2 Hand-arm vibration is mechanical vibration which is transmitted into the hands during a work activity
such as using hand-held power tools, for example needle scalers or angle grinders. Regular and frequent
exposure to hand-arm vibration can lead to permanent health effects collectively known as hand-arm
vibration syndrome, as well as specific diseases such as carpal tunnel syndrome. This is most likely whencontact with a vibrating tool or work process is a regular part of a seafarer‟s job. Occasional exposure isunlikely to cause ill health.
.3 Whole-body vibration is mechanical vibration which is transmitted into the body through thesupporting surface when seated or standing during a work activity, for example, riding in a rescue boat inchoppy seas. One of the primary health effects of whole-body vibration can be back pain.

SECTION 2
Risk Assessment.1 Risk Assessment for mechanical vibration.2 It is the ship owner‟s responsibility to ensure the levels of mechanical vibration to which seafarers are
exposed are assessed as part of a risk assessment. The risk assessment shall be based on –a. observation of specific working practices. This can be carried out by speaking to seafarers
on the vessel and their heads of department to find out if any of the shipboard tasks involve
regular exposure to vibration, examples of this could be –i.

seafarers are regularly using machinery such as needle scalers, floor polishers or
angle grinders;ii.

there are uncomfortable magnitudes of vibration emanating from the vessel itself;andPage 2 of 10

iii.

Seafarers are operating small craft at high speeds.

b. information provided by the manufacturer of the equipment and any other relevant
information on the probable magnitude of vibration in the particular conditions of use; andc.

if necessary a measurement of the level of mechanical vibration to which seafarers arelikely to be exposed.

.3 In determining if seafarers are at risk from exposure to mechanical vibration the following shall beconsidered –a.

the level, type and duration of exposure, including any exposure to intermittent vibration or
repeated shocks;b.

the exposure limit values and the exposure action values, and if they have been exceeded;c.

the health and safety of seafarers who may be particularly sensitive to mechanicalvibration: for example if a seafarer has an existing medical condition such as back pain;d.

any indirect effect on seafarers safety which may be caused by interaction between
equipment subject to mechanical vibration and the workplace or other work equipment;e.

the existence of replacement equipment designed to reduce exposure to vibration;f.

the extension of exposure to whole-body vibration beyond normal working hours;g.

the effect of specific working conditions, such as low temperatures; andh.

appropriate information obtained from health surveillance, including published information,so far as possible.

.4 The risk assessment shall –a.

record the significant findings, any measures the shipowner has taken or intends to take toeliminate or control the exposure to vibration and any information and training required to
be given to the seafarers;b.

(if appropriate) explain the reason why measurements of the levels of vibration have notbeen considered necessary;c.

be retained on the vessel for inspection purposes.

.5 The vibration assessment will have to be reviewed if there are any significant changes in work
conditions or if any health surveillance undertaken indicates a seafarer‟s health is being affected.
.6 Vibration levels can increase on a ship over time due to wear on machinery or a change of work
equipment so it is good practice to review the risk assessment at two yearly intervals.

SECTION 3
Measurement and evaluation of exposures to vibration
3.1 Maximum exposure levels

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.1 The daily exposure action value and daily exposure limit value are as follows –Hand-arm
Vibration

Whole-bodyVibration

Daily
Exposure
Action Value*

2.5m/s²

0.5m/s²

Daily
Exposure
Limit Value*

5.0m/s²

1.15m/s²

ActionRequired
Above this limit, theshipowner is requiredto a) reduce theseafarer‟s exposure;b) implement a
programme oforganisational or
technical measures;and c) provide
seafarers withinformation, instruction
and training.
This is the maximum
amount of vibration aseafarer may be
exposed to on any
single day. If thevibration levels areabove this limit the
shipowner shall identify
the reasons why thelimit has been
exceeded and takeaction to reduce theexposure below thisvalue. The
organisational or
technical measures
shall be amended toensure the limit is notexceeded again.

*Standardised to eight hour reference period.2 Daily exposure is the quantity of mechanical vibration to which a seafarer is exposed during a working
day, taking into account the magnitude and duration of the vibration.
3.2 Evaluation of exposures to vibration.1 Following the risk assessment it may be determined that it is not necessary to measure the levels of
mechanical vibration on the vessel. This may be for the following reasons –
a.

b.
c.

the handbooks for the mechanical machinery used by seafarers state the vibration levels areof a low value and when compared with the duration the seafarers use machinery it isconcluded the seafarer‟s exposure will be below the exposure action values ;the vessel‟s rescue boat is only used for short durations and the seafarers have been
instructed in how to operate the boat to minimise vibration;
following interviews with the seafarers it is concluded that certain areas of the vessel are
subject to vibration, however in these areas the vibration does not cause any discomfort andis considered to be of a low level.

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.2 The reasons why the levels of mechanical vibration have not been measured will have to be recordedon the risk assessment.
.3 If the risk assessment does indicate that some vibration exposures are likely to be above the exposure
action value then it would be advisable to have measurements taken to help determine if an exposure limit
value has been exceeded. Alternatively organisational or technical measures could be implemented toreduce the risk (refer to Section 4).
.4 Any measurements taken may include sampling which must be carried out to accurately represent thedaily exposure of a seafarer to the mechanical vibration being assessed. Measurements must also takeaccount of the particular characteristics of the mechanical vibration to be measured, ambient factors andthe characteristics of the measuring apparatus.
3.3 Evaluation of hand-arm vibration.1 If sufficient data is available from tool manufacturers it should be possible for a non-specialist to makean adequate estimate of vibration magnitudes. This can be carried out by using the following method toestimate the daily exposure for a seafarer –a.

the total daily duration of exposure to the vibration from each hand-tool or process being used
has to be calculated. The important information is the “trigger time” which is the time that theseafarer‟s hands are actually exposed to the vibration from the hand-tool or equipment. For
devices which need to be held with both hands, measurements must be made for each hand,then the exposure shall be determined using the higher value; andb.

the relevant vibration data for the equipment has to be obtained, this should be stated in the
manufacturer‟s handbook.

.2 By using this information the seafarer‟s daily exposure can be estimated by using the exposure
calculator which can be found on the UK‟s Health and Safety Executive (HSE) website www.hse.gov.uk/vibration . This method can be used to calculate up to six different tools or processes inorder to determine the total daily exposure.
.3 The conclusion of the risk assessment may be that more detailed measurements are required. This canbe a complex task and the person delegated to carry out the measurements will have to have sufficientcompetence and experience in carrying out vibration measurements, including –a.

thorough understanding of the measurement and analysis of hand-transmitted vibrationaccording to BS EN ISO 5349-1:2001 (refer to Section 8); andb.

training and practical experience in performing vibration testing on hand-tools.

.4 Further details for measuring and evaluating exposures to hand-transmitted vibration can be found in
the Maritime and Coastguard Agency publication: Code of Practice for Controlling Risks due to Handtransmitted Vibration on Ships.
3.4 Evaluation of whole-body vibration.1 It is not always necessary to measure seafarers‟ exposure to whole body vibration and on most vessels
the daily exposures will be below the limit value. It is generally the smaller fast craft when operated in
conditions that generate high levels of vibration or jolting that may exceed the exposure limit value. In mostcircumstances it is likely to be more effective for ship-owners to direct their efforts towards controlling therisks rather than trying to assess vibration exposures precisely.
.2 If the decision is made to check the vibration levels the information in the manufacturer‟s handbook canbe referred to, or the data published on the HSE website and the exposure calculator can be used www.hse.gov.uk/vibration.3 The person making the measurements must have sufficient competence and experience including –Page 5 of 10

a.

having a thorough understanding of the method of measuring and evaluating exposures
defined in ISO 2631-1:1997 (refer to Section 8); andb.

training and practical experience in performing vibration testing.

.4 Further details for measuring and evaluating exposures to whole-body vibration can be found in the
Maritime and Coastguard Agency publication: Code of Practice for Controlling Risks due to Whole-bodyVibration on Ships.
SECTION 4
Elimination or control of exposure to vibration in the workplace
4.1 Reducing the risks.1 The vibration regulations require that any risks arising from exposure to mechanical vibration which are
identified by the risk assessment are to be eliminated at their source. Where this is not possible and an
exposure action value is likely to be exceeded, the exposure shall be reduced to as low as is reasonably
practicable by establishing and implementing a programme of organisational or technical measuresappropriate to the activity. These measures may include –a.

looking for other working methods which eliminate or reduce exposure to vibration;b.

providing work equipment of appropriate ergonomic design which produces the least possible
vibration. For example: when purchasing a new hand-held sander, compare the vibration
emission date for different models;c.

vibration can be caused by wear and tear or misalignment of components, this can be
reduced by implementing appropriate maintenance programmes for work equipment, theworkplace and workplace systems;d.

improving the design and layout of workplaces and work-stations to minimise loads on
seafarers hand‟s, wrists and arms caused by poor posture;e.

providing adequate information and training to seafarers to ensure that work equipment isused correctly and safely in order to reduce exposure to mechanical vibration;f.

if seafarers are regularly using equipment such as chipping hammers, limits can be imposedon the duration and intensity of the use of such equipment;g.

providing protective clothing to keep seafarers warm and dry. This encourages good blood
circulation which helps to protect against developing vibration white finger;h.

adapting measures to seafarers who are particularly sensitive to vibration; andi.

taking into account the results from any health surveillance that has been carried out.

SECTION 5
Daily exposure limit value
5.1 Seafarers must not be exposed to mechanical vibration exceeding the daily exposure limit value.
.1 Following the implementation of the organisational or technical measures described in Section 4 theeffectiveness of such measures shall be re-assessed and if the daily exposure limit value has been
exceeded the ship-owner shall –a.

identify the reasons why the limit has been exceeded;

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b.

take such action as is necessary to reduce exposure to vibration to below the exposure limit
value ; andc.

amend the organisational and technical measures already taken to ensure that the limit is notexceeded again

SECTION 6
Information, training and health surveillance
6.1 Seafarer information and training.1 If seafarers are likely to be exposed to mechanical vibration in excess of an exposure action value theship-owner shall provide suitable information, instruction or training, to help seafarers minimise their
exposure as far as practical to the effects of vibration, this may include –a) the health effects of hand-arm and whole-body vibration;b) the measures taken in order to eliminate or reduce to as low as reasonably practicable therisks from mechanical vibration;c) the exposure limit values and the exposure action values;d) the circumstances in which seafarers are entitled to health surveillance;e) the potential injuries which may arise from the work equipment in use;f)ways to minimise risk which may include; changes to working practices, correct maintenanceof equipment and correct techniques for equipment use; andg) how to detect and report any health concerns related to mechanical vibration.
6.2 Health surveillance.1 The risk assessment may require that seafarers are to be provided with health surveillance. The
intention of health surveillance is to help prevent and diagnose rapidly any disorder linked with exposure tomechanical vibration.
.2 Health surveillance can be carried out by –a.
b.

regularly seeking information from seafarers by using a questionnaire; orusing an occupational health service provider to carry out the service.

.3 The results from health surveillance should be reviewed and analysed to check if the risk controls areworking. The seafarers shall always be informed about the results of any health surveillance and any
personal information about the health of individual seafarers shall be treated as confidential.

SECTION 7
Exemptions
7.1 Whole-body vibration and hand-arm vibration.1 The Gibraltar Maritime Administration may allow the exposure limit value to be exceeded in relation towhole-body vibration or hand-arm vibration where the seafarer is exposed to mechanical vibration which isusually below the exposure action value but which varies significantly from time to time and sometimes

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exceeds the exposure limit value. Before an exemption is issued under this circumstance the following
conditions must be met –a. the exposure value averaged over 40 hours is less than the exposure limit value;b. there is evidence to show that the risks from the pattern of exposure are lower than those fromexposure at the exposure limit value; andc. the seafarers concerned are subject to health surveillance to a level considered appropriate by the
Gibraltar Maritime Administration.
7.2 Application for an exemption.1 The application for exemption will need to cover the following areas –a. include a copy of the risk assessment and detail the work procedure for which the exemption issought, information on the seafarers affected, and the equipment used including frequency andlength of use;b. detail the heath surveillance that will be taken to monitor the safety of the seafarers concerned andthe steps being taken to reduce the risks; andc. qualified advice (such as from an occupational physician) may be used as supporting evidence.

SECTION 8
Standards used in this MLN
The following standards have been used in this MLN
8.1

Hand-arm vibration.1 „BS EN ISO standard 5349-1‟ means the British Standard publication “Mechanical vibration –Measurement and evaluation of human exposure to hand-transmitted vibration Part I: General
Requirements”;.2 The person carrying out the assessment of the level of exposure to hand-arm vibration shall basethe assessment on the following calculation, which is defined in chapters 4 and 5 and Annex A to BS
EN ISO standard 5349-1 –a. the daily exposure value shall be normalised to an eight hour reference period A(8), andexpressed as the square root of the sum of the squares (rms) (total value) of the frequency
weighted acceleration values, determined on the orthogonal axes ahwx, ahwy, and ahwz;

8.2

Whole-body vibration.1 „ISO 2631-1‟ means the International Organisation for Standardisation publication “Mechanicalvibration and shock – Evaluation of human exposure to whole-body vibration – Part 1: General
requirements”;.2 The person carrying out the assessment of the level of exposure to whole-body vibration shall basethe assessment on the following, which is in accordance with Chapters 5, 6 and 7, Annex A and Annex
B to ISO standard 2631-1 –a. the calculation of daily exposure expressed as equivalent continuous acceleration over aneight hour period, calculated as the highest (rms) value, determined on three orthogonal axes
(1,4awx, 1,4awy, awz, for a seated or standing seafarer);.3 Assessment of whole-body vibration need only include vibrations of a frequency exceeding 1 hz.

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8.3

Definitions.1 “Acceleration‟ means the quantity used to represent vibration magnitude in units of metres per
second per second (m/s2);.2 “orthogonal axes‟ means the three directions of vibration which are at right angles to one
another.

Alan Cubbin
Maritime Administrator
Issue date November 2012
All notices are available through www.gibraltarship.com
This copy of the Administrative Instruction has been sent electronically and does not carry a signature or official stamp. A sign andstamped copy will be available upon request

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Control of vibration on Gibraltar registered vessels
Objective – To protect seafarers from the risks related to exposure to vibration. (MLC A4.3b, B4.3.3,
A3.1.6h)
Health Surveillance
May be required following therisk assessment.

Risk Assessment. The shipownershall ensure that a risk assessment
is carried out to assess the levelof mechanical vibration to which
seafarers are exposed. If necessary
this may require a measurement of
the Exposure Limit Value andExposure Action Value for Hand-arm
vibration and Whole-body Vibration.

To be reviewed if there are
significant changes which
may affect its validity, or if
results of health surveillance
indicate there is a further
risk.
Daily Exposure Limit Value
Hand-arm = 5.0m/s²Whole-body = 1.15m/s²

A copy of the risk assessment is toremain on the vessel.
Daily Exposure Action
Value Hand-arm =2.5m/s²
Whole-body =0.5m/s²

If this limit is exceeded, suitable andsufficient information, instruction andtraining shall be provided to theseafarers.

If this limit is exceeded
the shipowner is required
to establish andimplement a programmeof organisational or
technical measures toreduce seafarer‟s
exposure to as low as isreasonably practicable.

This is the maximum amountof vibration a seafarer may
be exposed to on any single
day.

If this limit is exceeded the
shipowner shall identify thereasons why and take action
to reduce the exposure
below this value.

Once the organisational
and technical measures
have been completed theeffectiveness of themeasures shall be reassessed.

The effectiveness of thetechnical and/ororganisational measures
shall be re-assessed.

If it is found the Daily
Exposure Limit Value has
been exceeded

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