DRAFT UGANDA STANDARD  
  DUS 966-2 
Second Edition  
2021-mm-dd 
 
 
 Reference number  
DUS 966-2: 2021 
© UNBS 2021   
  
Surgical clothing — Specification - Part 2: Clean air suits  
 DUS 966-2: 2021  
ii © UNBS 2021  – All rights reserved  
 Compliance with this standard does not, of itself confer immunity from legal obligations  
A Uganda Standard does not purport to include all necessary provisions of a contract. Users are 
responsi ble for its correct application  
© UNBS 200 7  
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilised in any 
form or by any means, electronic or mechanical, including photocopying and microfilm, without pri or written 
permission from UNBS.  
Requests for permission to reproduce this document should be addressed to  
The Executive Director  
Uganda National Bureau of Standards  
P.O. Box 6329  
Kampala  
Uganda  
Tel: 256 41 4 505 995  
Fax: 256 41 4 286 123  
E-mail: unbs@infocom.co.ug  
Web: www.unbs.go.ug  DUS 966-2:2021  
© UNBS 2021 – All rights reserved  iii 
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ ............................  iv 
1 Scope  ................................ ................................ ................................ ................................ ......................  1 
2 Normative references  ................................ ................................ ................................ ............................  1 
3 Terms and definitions  ................................ ................................ ................................ .......................  112 
4 Requirements  ................................ ................................ ................................ ................................ ..... 334 
4.1 General requirement  ................................ ................................ ................................ .........................  334 
4.2 Performance requirements  ................................ ................................ ................................ ...................  4 
5 packaging  ................................ ................................ ................................ ................................ ...............  4 
6 Labelling  ................................ ................................ ................................ ................................ .................  4 
7 Sampling  ................................ ................................ ................................ ................................ ................  5 
Annex A (Informative)  Guidance to users for selecting products  ................................ ...............................  6 
A.1 General  ................................ ................................ ................................ ................................ ...................  6 
A.2 Performance levels  ................................ ................................ ................................ ................................  6 
A.3 Functional design aspects  ................................ ................................ ................................ ...................  6 
A.3.1  Size................................ ................................ ................................ ................................ ..........................  6 
A.3.2  Accessories  ................................ ................................ ................................ ................................ ...........  7 
A.4 Comfort  ................................ ................................ ................................ ................................ ...................  7 
A.4.1  General  ................................ ................................ ................................ ................................ ...................  7 
A.4.2  Clean air suits  ................................ ................................ ................................ ................................ ........  7 
Annex  B (informative)  Adhesion for fixation and wound isolation  ................................ ..............................  8 
Bibliography  ................................ ................................ ................................ ................................ ........................  9 
 DUS 966-2: 2021  
iv © UNBS 2021  – All rights reserved  
 Foreword  
Uganda National Bureau of Standards (UNBS) is a parastatal under the Ministry o f Tourism, Trade and 
Industry established under Cap 327 , of the Laws of Uganda.  UNBS is mandated to co -ordinate the 
elaboration of standards and is  
(a) a member of International Organisation for Standardisation (ISO) and  
(b) a contact point for the WHO/FAO Code x Alimentarius Commission on Food Standards, and  
(c) the National Enquiry Point on TBT/SPS Agreements of the World Trade Organisation (WTO).  
The work of preparing Uganda Standards is carried out through Technical Committees. A Technical 
Committee is establish ed to deliberate on standards in a given field or area and consists of key stakeholders 
including government, academia, consumer groups, private sector and other interested parties.  
Draft Uganda Standards adopted by the Technical Committee are widely circ ulated to stakeholders and the 
general public for comments. The committee reviews the comments before recommending the draft standards 
for approval and declaration as Uganda Standards by the National Standards Council.  
The committee responsible for this do cument is Technical Committee UNBS/TC 307, Med ical devices and 
equipment . 
This second edition cancels and replaces the first edition (US966: 2011, all parts), which has been technically 
revised.  DUS 966-2:2021  
© UNBS 2021 – All rights reserved  v 
 Introduction  
Clean air suits are used to minimize the spread  of infective agents to patients’ surgical sites and equipment, 
through prevention of dispersal of bacteria -carrying skin scales from the operating room staff, thereby helping 
to prevent post -operative surgical site infections.  
The performance required of working clothes for clinical staff varies with, for example, the type and duration of 
the procedure, and the susceptibility of the patient to infection. In infection -prone invasive operations, a clean 
air suit can contribute to reduction of infection risks , in conjunction with ventilation and correct working 
methods.  
 DRAFT UGANDA STANDARD  DUS 966-2: 2021  
 
© UNBS 2021 – All rights reserved  1 
 
 Surgical clothing — Specification - Part 2: Clean air suits  
1 Scope  
This Draft Uganda Standard specifies requirements, sampling and test methods fo r single -use and reusable 
surgical clean air  suits used as medical devices for patients, clinical staff and equipment intended to prevent 
the transmission of infective agents between patients and clinical staff during surgical and other invasive 
procedures.  
It does not apply to scrub  suits.  
2 Normat ive references  
The following referenced documents referred to in the text in such a way that some or all of their content 
constitutes requirements of this document. For dated references, only the edition cited applies. For undated 
references, the latest ed ition of the referenced document (including any amendments) applies.  
ISO 22612 , Clothing for protection against infectious agents — Test method for resistance to dry microbial 
penetration  
ISO 22610 , Surgical drapes, gowns and clean air suits, used as medic al devices, for patients, clinical staff and 
equipment — Test method to determine the resistance to wet bacterial penetration  
ISO 11737 -1, Sterilization of health care products — Microbiological methods — Part 1: Determination of a 
population of microorgan isms on products  
ISO 9073 -10, Textiles — Test methods for nonwovens — Part 10: Lint and other particles generation in the 
dry state  
ISO 811 , Textiles — Determination of resistance to water penetration — Hydrostatic pressure test  
ISO 13938 -1. Textiles — Bursting properties of fabrics — Part 1: Hydraulic method for determination of 
bursting strength and bursting distension  
ISO 9073 -3, Textiles — Test methods for nonwovens — Part 3: Determination of tensile strength and 
elongation  
ISO 11607  (all parts),  Packag ing for terminally sterilized medical devices  
US ISO 10993, Biological evaluation of medical devices  
3 Terms and definitions  
For the purposes of this document, the following terms and definitions apply. ISO and IEC maintain 
terminological databases for use  in standardization at the following addresses:  
— ISO Online browsing platform: available at http://www.iso.org/obp . DUS 966 -2: 2021  
2 © UNBS 2021  – All rights reserved  
 
 3.1  
clean air suit  
suit used as working garment intended and shown to minimize contamination of operating room air from skin 
scales origi nating on the skin of persons wearing it.  
3.2 
critical product area  
product area with a greater probability to be involved in the transfer of infective agent to or from the wound.  
3.3 
performance level  
discrete standard defined to classify products accordi ng to the performance requirements of this standard  
Note 1 to entry: With the introduction of two performance levels this document acknowledges the fact that products are 
challenged to differing extents during surgical procedures, dependent upon the microb ial cleanliness of the operating room 
required for the procedure  
3.3.1  
standard performance  
classification addressing minimum performance requirements for various characteristics of products used as 
medical devices in invasive surgical procedures  
3.3.2  
high performance  
classification addressing elevated performance requirements for various characteristics of products used as 
medical devices in invasive surgical procedures  
Note 1 to entry: Examples of surgical procedures where high performance level might be  considered are infection prone 
clean surgical procedures where air counts in the operating room of ≤ 10 CFU/m3 are required.  
3.4  
processor  
natural or legal person who processes products so that their performance complies with the requirements of 
this standard  
Note 1 to entry: A processor who places a product on the m arket is a manufacturer in the sense of this document.  
Note 2 to entry: A processor of reusable products is often referred to as a ‘reprocessor’ and processing reusable products 
is often referred to as ‘reprocessing’  
3.5  
processor  
natural or legal person  who processes reusable product items so that their performance complies with the 
requirements of this standard  
3.6  
resistance to microbial penetration  
ability of material(s) to withstand penetration of micro -organisms from one side through to the other  
3.6  
dry penetration  
effect of a combination of air movement and mechanical action by vibration on microbial penetration in dry 
condition  
3.8  
wet penetration  
effect of combination of wetness, pressure and rubbing on microbial penetration  DUS 966 -2: 2021  
 
© UNBS 2021  – All rights reserved  3 
 
 3.9  
reusable p roduct  
clean air suit intended  by the manufacturer to be reprocessed and reused  
3.10  
single -use product  
clean air suit intended by the manufacturer to be used for only one surgical procedure before disposal  
3.11 
surgical procedure  
surgical intervention penetrating skin or mucosa, performed by a surgical team  
3.12 
invasive surgical procedure  
procedure that reaches the inside of the body through the body surface  
3.1.3 
cleanliness  
freedom from unwanted foreign matter  
NOTE Such matter can be micro -organi sms, organic residues or particulate matter.  
3.4 
cleanliness — microbial  
freedom from population of viable micro -organisms on a product and/or a package  
3.15 
fixation  
adhesion of a surgical drape to the patient for the purpose of wound isolation  
3.16 
infective agent  
micro -organism that has been shown to cause a wound infection or that might cause infection in a member of 
the surgical team or the patient  
3.17 
manufacturer  
natural or legal person with responsibility for the design, manufacture, packagin g and labelling of a device 
before it is placed on the market under his own name, regardless of whether these operations are carried out 
by that person himself or on his behalf by a third party  
3.18 
colony forming unit  CFU 
unit by which  the culturable  number of microorganisms  is expressed  
Note  1 to entry:  The culturable  number  is the number  of microorganisms,  single  cells or aggregates,  able to form 
colonies on  a solid  nutrient  medium  
4 Requirements  
4.1 General requirement  
4.1.1  The clean air suit shall be  free from any damage o r defects.  DUS 966 -2: 2021  
4 © UNBS 2021  – All rights reserved  
 
 4.1.2  The biocompatibility of the clean air suits shall  be evaluated and approved for acceptable risk in  
accordance to the relevant part of US ISO 10993 . 
4.1.3 If the manufacturer does not differentiate the product areas, all areas shall meet the requirements for 
critical product area.  
4.2 Performance requirements  
Clean air suits  shall conform to the requirements given in Table 1 when tested in accordance with the test 
methods specified therein.  
Table 1  — Performance requi rements for clean air suit s 
S.No  Characteristic  Requirement  Test method  
Standard 
performance  High performance  
i Microbial penetration –dry, CFU  ≤ 100a ≤ 50a ISO 22612  
ii Cleanliness microbial /Bioburden 
(CFU/100cm2) ≤ 100 ≤ 100 ISO 11737 -1 
iii Particle release ,log 10 (lint count)  ≤ 4.0 ≤ 4.0 ISO 9073 -10 
iv Bursting strength ,kpa, dry  ≥ 40 ≥ 40 ISO 13938 -1 
v Tensile strength – Dry , N  ≥ 20 ≥ 20 ISO 9073 -3 
 a Test conditions: challenge concentration 108 CFU/g talcum and 30 minutes vibration time  
5 packaging  
5.1 The surgical clean air suits shall be packaged in suitable packaging materials, which shall protect 
product from contamination and dama ge during transportation, handling and storage.  
5.2 The packages shall be packed in accordance with ISO 11607 series. Only products of the same type 
and nominal size shall be packed together in a package and in a bulk container. Sterile -packed packages 
shall be packed in separate bulk containers.  
6 Labelling  
6.1 The packages shall be legibly and indelibly marked with the following information:  
a) name of product as “C lean air suit ”; 
b) name and physical address of manufacturer;  
c) type of surgical clothing “reusable ” or “single use”;  
d) performance level;  
e) country of origin;  
f) date of manufacture;  
g) date of expiry;  DUS 966 -2: 2021  
 
© UNBS 2021  – All rights reserved  5 
 
 h) batch or lot number;  
i) quantity of product;  
j) size of the surgical clothing;  
k) colour of surgical clothing;  
l) storage conditions;  
m) instruction of use; and  
n) instructions f or disposal after the useful life of the product  
6.2 In case of single use , the surgical clean air suits  shall be labelled sterile.  
6.3  In the case of the reusable clean air suits , information on the appropriate processes to allow reuse, 
including cleanin g, disinfection, packing and, if appropriate, the methods of sterilization of the device to be re -
sterilized, the number of reuses and any restriction to the reuse;  
6.4 if the surgical clean air suit is supplied with the intention that it be sterilized bef ore use, instructions for 
sterilization methods;  
7 Sampling  
Sampling shall be done in accordance with US ISO 2859 -1  DUS 966 -2: 2021  
6 © UNBS 2021  – All rights reserved  
 
 Annex A  
(Informative)  
 
Guidance to users for selecting products  
A.1 General  
The selection and use of clean air suits for specific surgical procedures should be covered by risk assessment 
and quality management and can be subject to local, regional or national infection prevention regime, 
guidelines, directives or regulations.  
A.2 Performance levels  
This standard introduces two performance lev els (‘standard performance’ and ‘high performance’) for  clean  air 
suits,  thereby  acknowledging  the fact that different  products  may be required  depending  on the microbial  
cleanliness  of the operating  room  required  for the procedure.  The differentiation  of ‘standard performance’ 
from ‘high performance’ products is based on the barrier performance of the  products.  For infection -prone  
clean  surgery,  air counts  in the operation  room  of less than 10 CFU/m3 are recommended.  To achieve that 
level, standard perform ance clean air suits can be used in  operating rooms with high air flow rates, but in 
operating rooms with average ventilation, e.g. 0,56 m3/s (equalling 17 air changes/h i n an average operating 
room),  high performance clean air suits are  needed,  particular ly when  the operation  requires a  high number  of 
persons  present.  
Note  1 For details  of the differences  in the required  barrier  performance,  see Table  1. 
By establishing  two performance  classes,  this document  facilitates  the assessment  of the barrier  perfor mance 
of products. This document does not include specific recommendations for selecting clean  air suits with regard  
to the type of surgical  procedure  the product  is to be used  with. 
The user should select clean air suits based on their performance levels in order to meet the anticipated  
challenges of the surgical procedure (e.g. in terms of duration, mechanical stress and temperature) and  the 
microbial  cleanliness  of the operating  room required  for the procedure.  
Note 2  In clean -room clothing systems,  not primarily intended for operating  room use,  the suit  has long  sleeves, is 
designed as a coverall, and is worn with a hood and textile boots. Such clothing systems have practical  drawbacks, such 
as difficulty in performing hand disinfection. In addition, gar ments made from tight materials can  impair the comfort of the 
wearer, particularly when performing physically heavy and stressful work such as large  surgical procedures. When a high 
performance clean air suit is required, e.g. in operating rooms with a low  air- flow where the clinician considers the patient 
to be particularly infection -prone, a complete clean -room clothing  system  can be  considered.  
A.3 Functional design aspects  
A.3.1  Size 
This standard  does  not include  provisions for  specifying  the size of products  in a standardized  way. Products 
should have suitable size and construction to fulfil the intended use of the clean air suit, and to  ensure  safety  
and freedom  of moments.  Selecting  products  of suitable  size to appropriately  cover  persons  is up  to the user.  DUS 966 -2: 2021  
 
© UNBS 2021  – All rights reserved  7 
 
 A.3.2  Accessories  
This standard  does  not include  specific  provisions  for accessories  like e.g. cuffs  or buttons.  Therefore, 
accessories need not to meet any requirements of this document, and the user should assess the functional 
design with consi deration to the placement of accessories so that the intended uses of the products are not 
compromised. The user should also assess the quality of any accessories in order to ensure that the intended 
uses of the products are not compromised.  
A.4 Comfort  
A.4.1 General  
A.4.1.1  The concept of comfort is based on several different factors, such as physiological comfort, ease 
of movement  or factors  that will influence  and/or  affect  the individual's  work  performance  and satisfaction with 
the product. Garments mad e from tight materials can impair the comfort of the wearer,  particularly  when  
performing  physically  heavy  and stressful  work  such  as large  surgical  procedures.  
A.4.1.2  The comfort of a product depends on such properties as its thermal resistance, air perm eability, 
water - vapour resistance, drapeability, tactile comfort and other properties like stretchability, weight, size, fit,  
fibres  and manufacture.  
Note  1 Drapeability  addresses  the ability  of a material  to conform  to a given  shape  or object.  
Note 2  Water-vapour resistance is defined as the water -vapour pressure difference between the two faces of a  
material  divided  by the resultant  evaporative  heat flux per unit area in the direction  of the gradient.  The evaporative heat 
flux can consist of both diffusi ve and convective components. EN 31092 provides a test method  for measuring the thermal  
and water -vapour  resistance  under  steady -state  conditions.  
Note 3  Thermal resistance is a property of a material that can be measured by a thermal manikin in view to  determine  
important  parameters  relevant  to clothing  thermal  comfort.  
Note 4  Tactile comfort also indicated as softness, is highly dependent on the fibre smoothness and the finish  
technologies.  
Note  5 Properties  such  as stretchability,  size fit, weight,  can be measured.  
A.4.1.3  Discomfort properties, such as rustling tendency, softness and skin irritation are difficult to 
measure.  Evaluation  should  be based  on trials of  the products  or practical  experience.  The user when 
selecting products for use should asses s the comfort of products in order to exclude any  significant limitations 
of the intended use of the product. Combinations of materials and design of  clothing systems  (including 
technical underwear or  garments) that will minimize the physiological  stress  during  work  are to be 
encouraged.  
A.4.2  Clean air suits  
The overall comfort of clean air suits can be influenced by a number of factors mentioned in A.4.1. Other  
important variables that can influence comfort include undergarments, health and physical condi tions,  
workload, mental stress and environmental conditions, such as temperature, relative humidity, and air  
changes in  operating  room.  The perception  of comfort  is subjective  and can be influenced  by one or a 
combination  of the aforementioned  factors.  DUS 966 -2: 2021  
8 © UNBS 2021  – All rights reserved  
 
 Annex B 
(informative)  
 
Adhesion for fixation and wound isolation  
Adhesives are used to attach fabrics during the preparation for an operation and to attach drapes to a patient 
on the operating table. Different adhesives are chosen for different materials, fo r example, material to material 
and material to the skin.  
In choosing an adhesive, the following considerations should be taken into account:  
a) adhesives should not cause damage to the skin.  
b) when used on reusable materials, the adhesives should be removable during reprocessing without 
damaging the fabric.  DUS 966 -2: 2021  
 
© UNBS 2021  – All rights reserved  9 
 
 Bibliography  
[1] EN13795 -2_2019, Surgical clothing and drapes — Requirements and test meth ods — Part 2 Clean air 
suits  
[2] ISO 13485:2016, Medical devices — Quality management systems — Requirements for reg ulatory 
purposes  
[3] US 966 -1:2011, Medical devices — Surgical gowns, drapes and clean air suits — Part 1: General 
requirements  
[4] US 966 -2:2011, Medical devices — Surgical gowns, drapes and clean air suits, — Part 2: Test 
methods  
[5] US 966 -3:2011, Medi cal devices — Surgical gowns, drapes and clean air suits, - Part 3 Performance  
requirements   
 DUS 966-2: 2021  
© UNBS 2021 – All rights reserved  11 
 
 Certification marking  
Products that conform to Uganda standards may be marked with Uganda National Bureau of Standards 
(UNBS) Certification Mark shown in the figure below.  
The use of the UNBS Certification Mark is governed by the Standards Act, and the Regulations made 
thereunder. This mark can be used only by those licensed under the certification mark scheme operated by 
the Uganda National Bureau of Standards and i n conjunction with the relevant Uganda Standard. The 
presence of this mark on a product or in relation to a product is an assurance that the goods comply with the 
requirements of that standard under a system of supervision, control and testing in accordanc e with the 
certification mark scheme of the Uganda National Bureau of Standards. UNBS marked products are 
continually checked by UNBS for conformity to that standard.  
Further particulars of the terms and conditions of licensing may be obtained from the Di rector, Uganda 
National Bureau of Standards.  
 
 DUS 966-2: 2021    
 
ICS 11.040.30 
Price based on nn pages  
© UNBS 2021 – All rights reserved