Respirator Maintenance

Use
Respiratory protection should be used when engineering or administrative controls are not practical, while controls are being instituted or during shut down for maintenance repair or emergency.

Selection of Respirator
See criteria in CSA Standard Z 94.4-93 (Section 6.3); available form Occupational Health and Safety.

Restrictions and Exceptions

1. An individual cannot be fitted with a respirator if they do not have sense of taste or smell. Ensure that prior to the qualitative fit test, a person can smell the product.
2. An individual cannot wear a respirator if they have facial hair that will interfere with the seal of the respirator.
3. Chemical cartridge respirators cannot be used with any substance that, if the individual were to be exposed, would be immediately dangerous to life and health.
4. Chemical cartridge or dust, mist fume respirators cannot be used with any substance that has poor warning properties (low odour, or poor eye, skin or respiratory warning properties)

Qualitative Fit Test Procedures

            Qualitative fit-testing will be carried out by a qualified person from the TRU Health and Safety Department. Contact      
            the OH&S Department to arrange an appointment to have fit-testing done.

Respirator Selection

1. The test subject should pick a respirator from 3 sizes (s, m,l)This should happen in a room separate from the fit test room to prevent odour fatigue. Prior to the process, the test subject needs to be shown how to put on the respirator, adjust straps etc. This does not constitute the subject’s formal training on respirator use, only a review. ‘The individual should wear the respirator for at least 5 minutes prior to the fit test occurring.
2. The test subject should now do the positive and negative pressure fit test as outlined below.
3. Ensure the respirator is in good working order. For example, check the half face-piece chemical cartridge respirator as follows:

   Retainer Ring	Ensure it is not cracked or warped and is capable of retaining the physical filter.
   Physical Filter for Dusts, Mists and Fumes	Check for NIOSH approval and condition of filter. The filter should be in front of the chemical cartridge and with the correct side facing out.
   Chemical Cartridge	Check for NIOSH approval, proper connection to the respirator and condition.
   Inhalation Valve	Ensure these valve flaps are clean and lie flat against the inhalation port.
   Exhalation Valve	Ensure valve guard is in place, that valve functions correctly and that valve and seal are clean.
   Face-piece	Ensure that face-piece is clean and is not warped or cracked, especially along the sealing surface that contacts the skin.

After putting on the respirator
Ensure there is an adequate seal between the face-piece and skin. Quick field tests of the seal are:
a. the inhalation (negative pressure) test, and
b. the exhalation (positive pressure) test

1. Inhalation Test
   Gently place the palm of the hands over the cartridge assemblies or inhalation points and breathe in
   1. If no air enters and the face-piece collapses slightly, the respirator is properly fitted and the exhalation valve is functioning properly.
2. Exhalation Test
   Gently place the palm of the hand or thumb over the exhalation valve guard and press lightly.
   1. Breathe out to cause a slight pressure inside the face-piece. If no air escapes, the face-piece is properly fitted and the inhalation valves are seating correctly.
   2. If air escapes, readjust respirator and test again, or check the condition of the exhalation valve.
   3. Be careful not to apply too much hand pressure when blocking valves as it may press the respirator against the face and improperly affect the test.

To Ensure Proper Fit
To ensure a good fit with respirators, do not permit any object or item to interfere with the face-piece seal. Cloth facelets around the face-piece, beards (in the area of respirator seal) and glasses (for full face-piece respirators) all will interfere with the seal. Some respirator manufacturers provide a modification of full face-piece masks that can accommodate glass lenses.

Respirator fit test

1. The respirator should be fitted with organic vapour cartridges
2. While the test conductor “puffs” the pre-packaged isoamyl acetate around the individuals face, the test subject should be performing the following test exercises and the rainbow passage.
   1. Normal breathing
   2. Deep breathing. Be certain breath are deep and regular
   3. Turning head form side to side. Be certain the movement is complete. Alert the test subject no to bump the respirator on the shoulders. Have the test subject inhale when his/her head is at either side.
   4. Nodding head up and down. Be certain motions are complete and made about every second. Alert the test subject not to bump the respirator on the chest. Have the test subject inhale when his/her head is in the fully up position.
   5. Talking. Talk aloud and slowly for several minutes. The following paragraph is called the rainbow passage. Reading it will result in wide range of facial movements and this is useful t to satisfy this requirement.
      
      Rainbow Passage:
      When the sunlight strikes raindrops in the air, they act like a prism and from a rainbow. The rainbow is a division of white light into many beautiful colours. These take the shape of a long round arch, with its path high above and its tow ends apparently beyond the horizon. There is according to legend a boiling pot of gold at one end. People look, but no one ever finds it. When a man looks for something beyond reach, his friends say he is looking for the pot of gold at the end of the rainbow.

Filter Changes

1. Change pre-filters on cartridges when breathing becomes difficult.
2. If using P 100 (formerly called HEPA) filters, change when breathing becomes difficult.
3. Change chemical cartridges when any breakthrough of a chemical odour is noticed. It is impossible to predict when such a breakthrough will occur with respirator cartridges. The use-life depends on several factors (i.e. level of exposure, type of chemical formulation, humidity and breathing rate of the worker). In addition, some cartridges do not absorb some types of vapour as effectively as others.
4. As a rough estimate, in moderately dusty or misty conditions, it is reasonable to expect about four hours of useful life for pre-filters. In moderate vapour exposure situations, eight hours of service life with chemical cartridges may be obtained.

Cold / Hot Weather Use
Ensure proper use of respirators in cold and hot weather. Low temperatures may fog lenses on full-face respirators. Anti-fogging compounds may help prevent fogging down to 0 C. For lower temperatures, nose cups that help direct the moist exhaled air away from the face piece so that it does not contact the lens are available with some respirators.

In hot weather, the stress of wearing a respirator can be reduced by using lightweight models and those which provide a powered flow of air.

Inspection and Cleaning
Inspect and clean respirators after each use. A recommended cleaning and maintenance procedure is:

1. Remove filters and cartridges
2. Examine the respirator for any damaged / defective parts. Follow the respirator manufacturer's instructions when replacing or repairing any defective parts.
3. Wash respirators (without cartridges) in warm water (50 C maximum) with a mild detergent or with a cleaner recommended by the manufacturer. Do not use strong detergents, hot water or solvents that may dissolve rubber parts. A stiff bristle (not wire) brush may be used to remove dirt.
4. Rinse respirator parts thoroughly in clean, warm water. Drain the respirator.
5. When the cleaning solution does not contain a sanitizing agent, respirator parts should be placed for two minutes in a sanitizing solution such as bleach (hypochlorite). This can be made by adding approximately 1 milliliter of laundry bleach to 1 litre of water at 50 C).
6. Re-rinse the respirator thoroughly in clean, warm water. (Detergents or sanitizers that dry on face-pieces may result in skin irritation. In addition, some sanitizers may cause deterioration of rubber or corrosion of metal parts if not completely removed.
7. Components should be dried with a clean, lint-free cloth or air dried.
8. Reassemble the respirator face-piece.
9. Test the respirator to ensure that all parts work properly.

Storage of Respirators

1. Store respirators in a clean zip lock bag, separate from cartridges
2. Store cartridges in a separate clean zip lock bag.
3. All items should be stored away from sunlight, solvents, extreme cold or heat, and excessive moisture.

Maintenance and Inspection
Maintain and inspect respirators routinely according to manufacturer's instructions. It is safe practice to use chemical cartridges within one year of purchase, even if never unwrapped.