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R A D I AT I O N
PERSONAL PROTECTIVE EQUIPMENT
PRACTICAL RADIATION TECHNICAL MANUAL
PERSONAL PROTECTIVE EQUIPMENT
INTERNATIONAL ATOMIC ENERGY AGENCYVIENNA, 2004
PERSONAL PROTECTIVE EQUIPMENTIAEA-PRTM-5 © IAEA, 2004 Permission to reproduce or translate the information in this publication may be obtained by writing to the International Atomic Energy Agency, Wagramer Strasse 5, P.O. Box 100, A-1400 Vienna, Austria.
Printed by the IAEA in Vienna April 2004
FOREWORDOccupational exposure to ionizing radiation can occur in a range of industries, such as mining and milling; medical institutions; educational and research establishments; and nuclear fuel facilities. Adequate radiation protection of workers is essential for the safe and acceptable use of radiation, radioactive materials and nuclear energy.
Guidance on meeting the requirements for occupational protection in accordance with the Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources (IAEA Safety Series No.
115) is provided in three interrelated Safety Guides (IAEA Safety Standards Series No. RS-G-1.1, 1.2 and 1.3) covering the general aspects of occupational radiation protection as well as the assessment of occupational exposure. These Safety Guides are in turn supplemented by Safety Reports providing practical information and technical details for a wide range of purposes, from methods for assessing intakes of radionuclides to optimization of radiation protection in the control of occupational exposure.
Occupationally exposed workers need to have a basic awareness and understanding of the risks posed by exposure to radiation and the measures for managing these risks. To address this need, two series of publications, the Practical Radiation Safety Manuals (PRSMs) and the Practical Radiation Technical Manuals (PRTMs) were initiated in the 1990s. The PRSMs cover different fields of application and are aimed primarily at persons handling radiation sources on a daily basis. The PRTMs complement this series and describe a method or an issue related to different fields of application, primarily aiming at assisting persons who have a responsibility to provide the necessary education and training locally in the workplace.
The value of these two series of publications was confirmed by a group of experts, including representatives of the International Labour Organization, in
2000. The need for training the workers, to enable them to take part in decisions and their implementation in the workplace, was emphasized by the International Conference on Occupational Radiation Protection, held in Geneva, Switzerland in 2002.
This Practical Radiation Technical Manual was developed following recommendations of a Technical Committee meeting held in Vienna, Austria, in November 1994 on the development, management and operation of a personal protective equipment system for use in radioactively contaminated environments. Major contributions to this PRTM were made by R. Wheelton, United Kingdom.
CONTENTS1–3 Restriction of exposure through the use of personal protective equipment 4–5 Proper use of personal protective equipment 6–7 System of personal protective equipment 8–9 Aprons, gloves and other shields against penetrating radiations 10–11 Laboratory and industrial suits to protect against radioactive contamination 12 Guide for choosing protective suits 13–14 Use of gloves for protection against radioactive contamination 15–16 Use of footwear for protection against radioactive contamination 17–18 Selection of respiratory protective equipment 19–24 Use of respirators 25–28 Use of breathing equipment 29 Other hazards 30 Warning signs and notices 31 Bibliography
IAEA PRACTICAL RADIATION TECHNICAL MANUAL
PERSONAL PROTECTIVE EQUIPMENT
This Practical Radiation Technical Manual is one of a series that has been designed to provide guidance on radiological protection for employers, radiation protection officers, managers and other technically competent persons who have responsibility for ensuring the safety of employees working with ionizing radiation. The Manual may be used with the appropriate IAEA Practical Radiation Safety Manuals to provide training, instruction and information for all employees engaged in work with ionizing radiation.
PERSONAL PROTECTIVE EQUIPMENT
Introduction Personal protective equipment (PPE) includes clothing or other special equipment that is issued to individual workers to provide protection against actual or potential exposure to ionizing radiations. It is used to protect each worker against the prevailing risk of external or internal exposure in circumstances in which it is not reasonably practicable to provide complete protection by means of engineering controls or administrative methods. Adequate personal protection depends on PPE being correctly selected, fitted and maintained.
Appropriate training for the users and arrangements to monitor usage are also necessary to ensure that PPE provides the intended degree of protection effectively.
This Manual explains the principal types of PPE, including protective clothing and respiratory protective equipment (RPE). Examples of working procedures are also described to indicate how PPE should be used within a safe system of work.
The Manual will be of most benefit if it forms part of a more comprehensive training programme or is supplemented by the advice of a qualified expert in radiation protection. Some of the RPE described in this Manual should be used under the guidance of a qualified expert.
1. RESTRICTION OF EXPOSURE
Workers can be protected against ionizing radiations by using either one or a
combination of the following means:
(A) Engineering controls (B) Administrative methods (C) Personal protective equipment (PPE).
Whenever it is reasonably practicable, protection should be provided ‘at the source’. This may involve selecting a radioactive substance of the most appropriate activity and form for a specific application, such as using a source of the minimum activity necessary and in a physical form that is least likely to spill. The term also implies that priority should be given to using engineering controls as a barrier around the source, automatically protecting workers in the vicinity against external and/or internal exposure. The practice should preferably be inherently safe by design.
Protection against external exposure may be achieved by using a combination of shielding and distance. Effective devices and warnings are needed to ensure that the source remains shielded and/or that the correct distance is maintained between the source and those who may potentially be exposed to the radiation hazards. Protection against internal exposure is achieved by containing radioactive substances and/or preventing their dispersal, to avoid causing contamination. Containment can be supplemented, if necessary, by further engineering controls such as extraction ventilation from a point (or points) close to where any dispersion is likely to occur. High efficiency particulate air (HEPA) filters incorporated into the ventilation system will remove radioactive particulates from the extracted air.
Administrative methods are less satisfactory than engineering controls because their effectiveness relies on the co-operation and awareness of individual workers to restrict exposures. For example, exposures might be restricted by limits on who may enter or on how long workers may remain inside controlled and supervised areas.
Engineering controls to contain radioactive material.
A tray is used to provide simple containment for minor spills and drips. A fume hood is necessary to adequately contain vapours from volatile radioactive substances. The fume hood must draw a sufficient draught of air to provide adequate engineering control. A glovebox is necessary to provide total containment during the manipulation of very hazardous materials such as fine powdered alpha emitters.
2. USE OF PERSONAL PROTECTIVE EQUIPMENT
As an administrative method to restrict exposure or, as a last line of defence, where neither engineering controls nor administrative methods are reasonably practicable, workers should use PPE. The use of PPE may be the only means of controlling the exposure of workers involved in emergency operations. PPE includes clothing or other special equipment that is issued to protect each exposed worker. It is essential that all persons involved in the management and use of PPE are aware of its capabilities and limitations, in order to ensure that an adequate, reliable and planned degree of personal protection is provided.
Different PPE may be used to protect against external and internal exposures.
Protective clothing may be designed to shield large areas of the wearer’s body or individual organs, such as the eyes, against external irradiation. However, protective clothing and equipment is more frequently used to prevent radioactive substances either making direct contact with or entering the body and delivering internal exposures.
Respiratory protective equipment (RPE) is intended to prevent the inhalation of radioactive substances which would result in radiation doses to the lungs and other organs into which the substance(s) might ultimately pass or which might be irradiated by them.
Administrative controls and PPE in support of engineering controls.
Engineering controls: The bench profile is designed to contain a spill and the location of the integral sink and the electrical socket minimizes the buildup of radioactive contamination.
Administrative controls: The warning notice and a tag on the drainpipe to prevent unauthorized workers entering a contaminated pipe provide administrative controls.
Personal protective equipment is used as a last line of defence.
3. THE SELECTION OF PERSONAL PROTECTIVE EQUIPMENT
Three essential items of information are necessary before selecting PPE:
The nature of the exposure. Both qualitative and quantitative information (A) is needed about conditions in the workplace. Surveys, as described in the Manual on Workplace Monitoring for Radiation and Contamination (IAEA-PRTM-1), can be performed to determine the radionuclide(s) present, the type of potential exposure(s) and magnitude of possible doses, the physical form of the radiation source(s), and the nature and concentration(s) of any contamination. The radiological risks need to be considered together with other hazards to appreciate the difficulties of accomplishing the work wearing PPE.
Performance data for PPE. Data are needed to assess the ability of (B) available and/or approved PPE to reduce the particular exposure(s).
This information will usually be available from the manufacturers, who will have carried out tests under controlled conditions as specified in international or national regulations and standards.
The acceptable level of exposure. PPE should aim to minimize or even (C) to eliminate exposure. In practice a decision will be made, preferably by a qualified expert, on whether the PPE could in theory provide adequate protection below internationally agreed dose limits or other constraints.
The nature of any potential exposure in the workplace is assessed.
Measurements are made using personal air samplers (belt mounted) and surface and airborne contamination monitors to assess working conditions. Any contaminants present need to be analysed to provide information necessary to select suitable PPE.
Maximum protection will only be obtained in practice if the PPE is fitted, used and maintained to the standards specified for the manufacturer’s tests.