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PPE are manufactured in limited ranges of size for workers of average build, often of a single gender group only. It may be necessary to try different products of a similar specification to find PPE that is comfortable and a good fit and that provides the necessary protection. The workers’ training must emphasize the need to fit and use the personal protection correctly each time.
PPE needs to be routinely cleaned, checked and maintained in accordance with the manufacturer’s recommendations. The users can be relied upon to carry out or to arrange for cleaning but appropriate arrangements must be in place. For example, either there must be a central system for cleaning or suitable materials must be supplied, both to encourage the action and to ensure that unsuitable cleaning methods or agents are not used. A central system for cleaning facilitates the carrying out of checks, maintenance and repairs. This maintains the level of protection and helps to prolong the life of the PPE. The use of disposable PPE reduces the need for maintenance, but it will still be necessary, for example, to maintain dispensers and to dispose of contaminated clothing.
PPE should be selected to fit individual workers. The training of workers should emphasize the need to use PPE correctly and equipment should be checked and maintained regularly.
5. INFORMATION, INSTRUCTION AND TRAINING
Their needs differ but may include the following, for example:
– The manager responsible for the system needs information on appropriate surveys, on the selection of suitable equipment and literature from the manufacturer of the equipment. Management skills are necessary to set up an appropriate system and to maintain its effectiveness in practice.
– Workers need instruction on the specific hazards of the workplace and the consequences of unprotected exposure. Their training should include where, when and how protective equipment is obtained, fitted, used and cleaned. They will also need to recognize faulty equipment and hazards which may arise from use of the equipment.
– Storekeepers need to know how to store and issue the correct equipment properly.
– Maintenance and cleaning staff need to be trained in how to clean equipment properly, how to assess damage and wear, and how to ensure effective repair or replacement. The potential exposure of cleaning staff must be taken into account.
– Supervisors need all of the above and clear instructions which define their responsibilities. They need to provide for refresher training and to ensure that recruits to the system receive appropriate and adequate initial information, instruction and training.
Managers, users, storekeepers, maintenance staff and supervisors will have specific requirements for appropriate information, instruction and training.
The effectiveness of PPE depends on good management, supervision and monitoring of the system. The system needs to be defined in written procedures with the full support and commitment of senior management. PPE may make work more difficult or more demanding and may not be popular with all workers. Managers and supervisors need to recognize this and to set an example by using personal protection whenever, and for however short a time, they enter areas in which the system is in place.
Supervisors need to monitor whether the protective equipment is being used correctly and consistently; whether it is being cleaned and maintained; and whether provisions for training are being utilized and are adequate. They also need to be alert to possible problems, such as changes in conditions that might render the PPE inadequate, or hazards which the PPE might create or exacerbate (see Section 29).
Supervisors and workers need to keep managers informed of changes in the workplace or processes and changes or improvements in available PPE.
There must be clear guidelines for any disciplinary action(s) that would be taken against workers who do not comply with obligations under the system.
To ensure that it provides the intended protection, a system of work has to be set down in writing and everyone involved in it has to comply with the requirements. The system has to be adapted to meet changes as they arise.
Whenever there is a potential for occupational exposure to ionizing radiation, a prior evaluation of the radiological risks is necessary in order to consider the need for classifying the working area. Workplaces are designated as controlled areas if specific protective measures or safety provisions are or
could be required for:
(A) Controlling exposures or preventing the spread of contamination in normal working conditions, and (B) Preventing or limiting the extent of potential exposures.
Although specific protection measures and safety provisions are not normally necessary, the working area is classified as a supervised area if it is not already designated as a controlled area but if the conditions of occupational exposure need to be kept under review.
The system of work for a designated area should include the use of PPE if its use would be reasonably practicable, and if it would potentially either reduce the doses to those who work in the area or prevent the dispersal of contamination from the designated area. If the protective equipment is essential, access to the area must be restricted and the PPE should be specified as a condition of entry, such as on a written permit to work in the area. Under these circumstances barrier discipline is essential.
Routine and task related monitoring should be performed as described in the Manual on Workplace Monitoring for Radiation and Contamination (IAEAPRTM-1). The Manual on Individual Monitoring (IAEA-PRTM-2) describes methods to verify the effectiveness of the practices for control of radiation.
The validity of using PPE and the possibility of replacing it with more suitable engineering controls or redesigned processes should be considered in regular assessments.
Specific protective measures or safety provisions apply in controlled areas.
The extent of controlled areas should be clearly defined. Where practicable, the boundaries coincide with fixed barriers, such as the walls and doors of a room.
Notices are posted to display appropriate warnings and to prohibit unauthorized access.
Flexible aprons with a thickness up to the equivalent of 1/3 mm of lead (written as 0.33 mmPb) are available to shield the upper torso. Double sided aprons shield the chest and the back against radiations scattered behind the body.
The aprons attenuate, by about 90%, low energy radiations such as scattered X rays (of tens of keV). However, these aprons are ineffective against the more penetrating primary X rays and gamma radiations (above 100 keV) used more widely in nuclear medicine, radiotherapy and industry.
Wearing an apron for prolonged periods is tiring, which is why garments do not incorporate more substantial shielding. The aprons are cumbersome and may slow down work and thus result in higher personal doses if they do not provide adequate protection.
Aprons must be stored flat or on rounded hangers. Folding or creasing causes cracks or wear in the shielding. Such damage, although minor, may lead to repeated exposure of the same area of the body. An outer fabric cover may need to be removed to inspect the shielding visually. More thorough examinations, including radiographic or fluoroscopic tests, should be carried out periodically (annually). Damaged aprons should be discarded or clearly labelled as being only for uses other than as a body radiation shield. The outer cover can usually be wiped clean with water and mild detergent.
Aprons provide insignificant protection against the more penetrating radiations.
Inappropriate use of aprons can increase personal exposures. Storage conditions and checks are essential to avoid using damaged aprons.
Shielding gloves and sleeves containing up to 0.33 mmPb are manufactured.
Like aprons, they are ineffective shields against most radiations other than electrons (beta particles) and low energy scattered X rays.
Wearing the gloves reduces dexterity and consequently, if used inappropriately, will result in significant hand doses and greater body doses by prolonging the exposure.
The sleeves are flexible and, when used as local shielding, provide good cover for the extremities. The double thickness provides better protection against external exposure and leaves the fingers free to accomplish the task in the minimum time and with the minimum dose.
Gloves and sleeves must be stored flat. Folding or creasing causes cracks or wear in the shielding. These may be minor but may reduce the level of protection. An outer fabric cover may need to be removed to inspect the shielding visually. More thorough examinations, including radiographic or fluoroscopic tests, should be carried out periodically (annually). The outer cover can be wiped clean with water and mild detergent but severe contamination is problematic.
Gloves and sleeves give poor protection against the more penetrating radiations.
Sleeves used as local shielding provide better protection. Wearing gloves reduces dexterity. Storage conditions and checks are essential to avoid using damaged shielding.
Laboratory coats (labcoats) made of cotton or synthetic fibres are commonly used in research laboratories and hospital departments where there is a risk of minor radioactive contamination. The conditions of the work, such as whether flammability needs to be considered, are a factor in the selection of the fabric. Short jackets and smocks do not protect the lower body. Full length coats need to be fully fastened to ensure that spills or splashes of radioactive substances do not contaminate personal clothing underneath. Labcoats that fasten along one shoulder and the side of the body provide better coverage.
Strip fasteners (such as ‘Velcro’), instead of buttons, allow the garment to be removed more easily following a spill. Additional protection can be obtained by wearing a disposable plastic bib apron over a labcoat when there is an increased risk of contamination.
Labcoats protect the wearer but also serve to contain any contamination inside the designated area. Labcoats should always be monitored after working with radioactive substances. Barrier discipline dictates that labcoats should not be worn outside the designated areas. Storage lockers or hangers should be provided inside the designated areas.
Labcoats should always be monitored for contamination before being laundered. A coloured collar or pocket covers can help to identify garments that are subject to this routine. Seriously contaminated garments need to be decontaminated, perhaps by soaking or allowing a period of time for radioactive decay, before being sent to the laundry. Seams in particular should be carefully checked before reuse to ensure that persistent contamination will not continue to irradiate the body surface underneath.
Labcoats and aprons protect against radioactive contamination.
Protective clothing needs to cover the parts of the body likely to be exposed to contamination. Clothing is not worn outside the designated area(s) and is monitored and decontaminated as necessary.
One piece suits, coveralls, overalls or ‘slicker suits’ are used at industrial workplaces to protect against radioactive contamination the parts of the body covered by the clothing.
Suits are available with or without integrated head cover or hood to allow use with different types of RPE (see later sections). Elasticated hoods and arm and leg cuffs give more comfort and ensure that body surfaces remain covered.