Respirator inspection, cleaning, maintenance and storage
Introduction
Scrupulous respirator maintenance should be made an integral part of the overall respirator program. Manufacturers' instructions for inspection, cleaning and maintenance of respirators should be followed to ensure that the respirator continues to function properly. Wearing poorly maintained or malfunctioning respirators may be more dangerous than not wearing a respirator at all. The worker wearing a defective device may falsely assume that protection is being provided. Emergency escape and rescue devices are particularly vulnerable to inadequate inspection and maintenance because they generally are used infrequently, and then in the most hazardous and demanding circumstances. The possible consequences of wearing a defective emergency escape and rescue respirator are lethal.
The OSHA standards strongly emphasize the importance of an adequate maintenance program, but permit its tailoring to the type of plant, working conditions and hazards involved. However, all programs are required to include provisions for the following:
- Inspection for defects
- Cleaning and disinfecting
- Repair
- Storage
Your maintenance procedures, described in your written program, should include the frequency for changing air-purifying cartridges. A proper maintenance program ensures that the worker's respirator remains as effective as when it was new.
Disposable air-purifying respirators do not require the inspection,
cleaning and maintenance steps needed for the reusable types
of respirators. However, an uncontaminated and protected storage
area is needed where replacement respirators are stored.
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Inspection for defects
Probably the most important part of a respirator maintenance program is frequent inspection of the devices. If conscientiously performed, inspections will identify damaged or malfunctioning respirators before they can be used. The OSHA requirements outline two primary types of inspection, (1) before each use, and (2) while it is being cleaned. In a small operation, where workers maintain their own respirators, the two types of inspection become essentially one and the same. In a large organization with a central respirator maintenance facility, the inspections differ. A sample respirator inspection record is included at the end of this section.
Frequency of inspection
OSHA requires that all respirators used in routine situations be inspected before each use and during cleaning. Respirators maintained for use in emergency situations are to be inspected at least monthly and in accordance with the manufacturer's recommendations, and be checked for proper function before and after each use. Emergency escape-only respirators are to be inspected before being carried into the workplace for use.
NIOSH recommends that all stored SCBA be inspected weekly because it is highly unlikely that anyone needing a respirator in a hurry, as during an emergency, is going to inspect it. In fact, it could be dangerous to take time to do so.
Inspection procedures
Inspection procedures differ depending upon whether air-purifying or atmosphere-supplying devices are involved, and whether the inspection is to be conducted in the field during use or during routine cleaning.
The OSHA standard requires that respirator inspection includes the following:
- A check of respirator function.
- A check of the tightness of the connections.
- A check of the facepiece, head straps, valves, connecting tube, and cartridges, canisters or filters.
- A check of elastomeric parts for pliability and signs of deterioration.
- A check of the regulator and warning devices on SCBA for proper functioning.
- Ensuring that air and oxygen cylinders are maintained in a fully charged state and are recharged when the pressure falls to 90% of the manufacturer's recommended pressure level.
For respirators maintained for emergency use, the inspections also need to:
- Certify the respirator by documenting the date the inspection
was performed, the name (or signature) of the person who
made the inspection, the findings, required remedial action,
and a serial number or other means of identifying the inspected
respirator; and,
-
Provide this information on a tag or label
that is attached to the storage compartment for the respirator,
is kept with the respirator or is included in inspection
reports stored as paper or electronic files. This information
must be maintained until replaced following a subsequent
inspection and certification.
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Field inspection of air-purifying respirators
 Routinely used air-purifying respirators should be checked as follows before and after each use:
- Examine the facepiece for:
- Excessive dirt
- Cracks, tears, holes or distortion from improper storage
- Inflexibility (stretch and massage to restore flexibility)
- Cracked or badly scratched lenses in full facepieces
- Incorrectly mounted full facepiece lens or broken or missing mounting clips
- Cracked or broken air-purifying element holder(s), badly worn threads or missing gasket(s) (if required).
- Examine the head straps or head harness for:
- Breaks
- Loss of elasticity
- Broken or malfunctioning buckles and attachments
- Excessively worn serrations on the head harness which might permit slippage (full facepiece only).
- Removing the exhalation valve(s) and examine the valve for:
- Foreign material, such as detergent residue, dust particles or human hair under the valve seat
- Cracks, tears or distortion in the valve material
- Improper insertion of the valve body in the facepiece
- Cracks, breaks or chips in the valve body, particularly in the sealing surface
- Missing or defective valve cover
- Improper installation of the valve in the valve body.
- Examine the air-purifying element for:
- Incorrect cartridge, canister or filter for the hazard;
- Incorrect installation, loose connections, missing or worn gaskets, or cross-threading in holder
- Expired shelf-life date on cartridge or canister
- Cracks or dents in outside case of filter, cartridge or canister
- Evidence of prior use of sorbent cartridge or canister, indicated by absence of sealing material, tape, foil, etc., over inlet.
- If the device has a corrugated breathing tube, examine it for:
- Broken or missing end connectors, gaskets or 0-rings
- Missing or loose hose clamps
- Deterioration, determined by stretching the tube and looking for cracks.
- Examine the harness of a front- or back- mounted gas mask for:
- Damage or wear to the canister holder which may prevent it being held securely in place
- Broken harness straps or fastenings.
Field inspection of atmosphere-supplying respirators
For a routinely used atmosphere-supplying respirator, use the following procedures.
- If the respirator has a tight-fitting facepiece, use the procedures outlined above for air-purifying respirators to inspect the facepiece and straps. Skip the steps pertaining to air-purifying elements.
- If the device is a hood, helmet, blouse or full suit, use the following procedures:
- Examine the hood, blouse or full suit for rips and tears, seam integrity, etc.
- Examine the protective headgear, if required, for general condition, with emphasis on the suspension inside the headgear.
- Examine the protective faceshield, if any, for cracks or breaks or impaired vision due to rebounding abrasive particles.
- Make sure that the protective screen is intact and secured correctly over the faceshield of abrasive blasting hoods and blouses.
- Examine the air supply system for:
- Integrity and good condition of air supply lines and hoses, including attachments and end fittings
- Correct operation and condition of all regulators, valves or other air-flow regulators.
On SCBA, determine that the high-pressure cylinder of compressed air or oxygen is sufficiently charged for the intended use, preferably fully charged (mandatory on an emergency device). On closed circuit SCBA, make sure that a fresh canister of CO2 sorbent is installed before use, or in accordance with manufacturers' instructions. On open-circuit SCBA, recharge the cylinder if less than 80 percent of the useful service time remains. However, it is much preferred that an open-circuit SCBA be fully charged before use.
When an air-purifying or atmosphere-supplying device is used nonroutinely, all the above procedures should be followed after each use. OSHA requires that devices for emergency use be inspected once a month and that "a record shall be kept of inspection dates and findings for respirators maintained for emergency use." NIOSH recommends that such inspections be conducted at least weekly, because of the hazard that undetected loss of breathing gas from emergency SCBA will present to the wearer.
If defects are found during any field inspection, two remedies are possible. If the defect is minor, repair and/or adjustment may be made on the spot. If it is major, the device should be removed from the service until it can be repaired. UNDER NO CIRCUMSTANCE SHOULD A DEVICE THAT IS KNOWN TO BE DEFECTIVE BE USED OR STORED FOR FUTURE USE.
Inspection during cleaning
Because respirator cleaning usually involves some disassembly,
it presents a good opportunity to examine each respirator
thoroughly. The procedures outlined above for a field inspection
should be used, but only after the respirator is cleaned and
reassembled prior to returning it to service.
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Cleaning and disinfecting
OSHA requires the employer to provide each respirator user with a respirator that is clean, sanitary and in good working order.
The respirators should be cleaned and disinfected at the following intervals:
- Respirators issued for the exclusive use of an employee shall be cleaned and disinfected as often as necessary to be maintained in a sanitary condition.
- Respirators issued to more than one employee shall be cleaned and disinfected after each use.
- Respirators used in fit testing and training shall be cleaned and disinfected after each use.
In a large respirator program in which respirators are used routinely, they should be exchanged daily for cleaning and inspection. In a small program involving only occasional respirator use, this period could be weekly or monthly. Each worker who maintains a respirator should be thoroughly briefed on cleaning and disinfecting it. Although a worker may not be required to maintain the respirator, briefings on the cleaning procedure will encourage acceptance of the respirator by providing assurance that the worker will receive a clean, disinfected, properly maintained device. This is particularly important where respirators are not individually assigned. Where respirators are individually assigned, they should be durably identified to ensure that the worker always receives and uses the same device. Identification markers should neither penetrate the facepiece nor block filters, cartridge ports or exhalation valves.
In a large program, there may be a centralized cleaning and maintenance facility with specialized equipment and personnel trained in respirator maintenance. A good facility has separate areas for disassembly of used respirators and assembly of freshly cleaned and maintained devices which ensure that the clean respirators do not become contaminated. Also, there is ample storage space for the clean respirators, and spare parts (filters, exhalation valves, headbands, etc.) are readily available. There is also a test bench for checking the operation of SCBA regulators as well as a leak test system.
Disassembly
The used respirators are collected and deposited in a central location. They are taken to an area where the filters, cartridges or canisters are removed and discarded. Canisters and cartridges should be intentionally damaged to prevent reuse. If the facepieces are equipped with reusable dust filters, they may be cleaned with compressed air in a hood. The air tanks from SCBA are removed and connected to a charging station, and the rest of the unit is sent to a SCBA test bench where the regulator is tested. SCBA facepieces are cleaned like air-purifying respirator facepieces.
CAUTION: Improper disposal of an oxygen-generating canister from a closed circuit SCBA is dangerous. The manufacturer's instructions should be carefully followed when disposing of the canisters.
Cleaning and sanitizing
Respirators should be cleaned and disinfected using the procedures in Appendix B-2 of OSHA standard 1910.134, or the manufacturer's instructions, provided that such procedures are equally effective.
The actual cleaning may be done in a variety of ways. A standard domestic type clothes washer may be used if a rack is installed around the agitator to hold the facepieces in fixed positions. If the facepieces are placed loose in a washer, the agitator may damage them. A standard domestic dishwasher also may be used, but it is not preferred because it will not immerse the facepieces.
Any good detergent may be used, but cleaner and sanitizer solutions that clean effectively and contain a bactericide are available.
Reliable, effective disinfectants may be made from readily available household solutions, including:
- Hypochlorite solution (50 ppm of chlorine) made by adding approximately two ml of hypochlorite (laundry) bleach to one liter of water. A two-minute immersion disinfects the respirators.
- Aqueous solution of iodine (50 ppm of iodine) made by adding approximately 0.8 ml tincture of iodine per liter of water. The iodine is approximately 7 percent ammonium and potassium iodide, 45 percent alcohol, and 48 percent water. Again, a two-minute immersion is sufficient.
If the respirators are washed by hand, a separate disinfecting rinse may be provided. If a washing machine is used, the disinfectant should be added to the rinse cycle, and the amount of water in the machine at that time will have to be measured to determine the correct amount of disinfectant.
Respirator cleaning kits that include the necessary cleansers and sanitizers, a bucket and brush for hand cleaning, are available commercially.
Rinsing
The cleaned and disinfected respirators should be rinsed thoroughly in clean water (140° F maximum) to remove all traces of detergent, cleaner and sanitizer and disinfectant. This is very important to prevent dermatitis.
Drying
The respirators may be allowed to dry by themselves on a clean surface. They also may be hung from a horizontal wire, like drying clothes, but care must be taken not to damage the facepieces. Another method is to use a commercially available, electrically heated steel storage cabinet with a built-in circulating fan, and replacing the solid shelves with steel mesh, if necessary.
Reassembly and inspection
The clean, dry respirator facepieces should be reassembled and inspected in an area separate from the disassembly area to avoid contamination. The inspection procedures have been discussed, but there may be more things to look for because of the cleaning. The most common is detergent or soap residue left by inadequate rinsing. This appears most often under the seat of the exhalation valve, and can cause valve leakage or sticking.
At this time, the respirators should be thoroughly inspected and all defects corrected. New or retested filters, or new cartridges and canisters should be installed, and the completely reassembled respirator should be tested for leaks.
The facepiece of a SCBA can now be combined with the tested
regulator and a full charged cylinder, and an operational
check can be performed.
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Maintenance and repair
Respirators that fail an inspection or are otherwise found to be defective are to be removed from service, and be discarded, or repaired or adjusted in accordance with the following procedures:
- Repairs or adjustments to respirators are to be made only by persons appropriately trained to perform such operations and shall use only the respirator manufacturer's NIOSH-approved parts designed for the respirator.
- Repairs are to be made according to the manufacturer's recommendations and specifications for the type and extent of repairs to be performed.
- Reducing and admission valves, regulators, and alarms are to be adjusted or repaired only by the manufacturer or a technician trained by the manufacturer.
Maintenance personnel should be thoroughly trained. They should be aware of their limitations and never try to replace components or make repairs and adjustments beyond manufacturer's recommendations, unless they have been specially trained by the manufacturer.
These restrictions apply primarily to maintenance of the more complicated devices, especially closed and open circuit SCBA, and even more specifically their reducing or admission valves (regulators) which shall be returned to the manufacturer or to a trained technician for adjustment or repair. There should be no major difficulty in repairing and maintaining most other respirators, particularly the most commonly used air-purifying types.
An important aspect of any maintenance program is having
enough spare parts on hand. Only continual surveillance of
replacement rate will determine what parts in what quantities
should be kept in stock. It is desirable to have some sort
of recordkeeping system to indicate spare parts usage and
the inventory on hand.
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Storage
All the care that has gone into cleaning and maintenance of a respirator can be negated by improper storage. OSHA requires that respirators be stored to protect against:
- mechanical damage
- contamination
- dust
- sunlight
- extreme temperatures
- excessive moisture
- damaging chemicals
Respirators should also be packed or stored to prevent deformation of the facepiece and exhalation valve.
Leaving a respirator unprotected, as on a workbench, or in a tool cabinet or tool box among heavy wrenches, grease and dirt may damage it.
It is strongly recommended that freshly cleaned respirators be placed in heat-sealed or reusable plastic bags until reissue. They should be stored in a clean, dry location away from direct sunlight. They should be stored in a single layer with the facepiece and exhalation valve in a more or less normal position to prevent the rubber or plastic from taking a permanent distorted "set."
Air-purifying respirators kept ready for nonroutine or emergency use should be stored in a cabinet. The storage cabinet should be readily accessible, and all workers should be made aware of its location, as is done for fire extinguishers. Avoiding serious injury from inhalation of a toxic substance may depend entirely on how quickly workers can get to the emergency respirators. This type of storage should be encouraged for routinely used respirators if it does not interfere with the normal work routine. A little inconvenience here is justified to prevent use of a respirator damaged by improper storage.
A chest or wall-mounted case may be purchased from the respirator manufacturer for storing a SCBA for use in emergencies. Again, the location of SCBA should be well known and clearly marked. Unlike fire extinguishers, however, they should be located in an area that will predictably remain uncontaminated. Even highly trained workers take 30 seconds to one minute to put on these devices. In a highly contaminated atmosphere such as might be created by massive release of a toxic material, this may be too long a time to stay safely in the area. Therefore, the first reaction should be to escape to an uncontaminated area, then put on the SCBA which should be located there and re-enter the hazardous area for whatever task must be done. There are undoubtedly exceptions to this general rule, and only thorough evaluation of the potential hazard, taking into account the physical configuration of the work area, will permit a final decision about the correct storage location for a SCBA.
Routinely used respirators may be stored in a variety of ways if they are protected against the substances and conditions listed at the beginning of this section. This means that when a respirator is not in use, it should be stored in a plastic bag inside a rigid container.
The adequately trained worker should develop respect for respirators which will automatically provide incentive to protect it from damage. Besides providing better assurance of adequate protection, this training will lower maintenance costs because of decreased damage.
Sample Respiratory Inspection Record
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