Toolbox Topic: Respirator Protection
Respiratory Protection Programs are designed to protect employees by establishing standard practices for use, selection, storage, care, and training. In this episode, we will discuss all that and more!
Respirator Protection Definitions
According to OSHA 1910.134(a)(2), a respirator must be provided to employees when such equipment is necessary to protect the employee’s health. The employer must provide the applicable and suitable respirators for the intended purpose.
A respirator is an apparatus worn over the mouth and nose or the entire face to prevent the inhalation of dangerous substances.
There are different types of respirators. There are air-purifying respirators, demand respirators, negative pressure, and positive pressure respirators. There are powered air-purifying respirators, pressure-demand respirators, self-contained breathing apparatuses, and supplied air respirators. There are even escape-only respirators intended for emergency use. All these respirators are different, but the goal is the same, to keep you safe!
History of Respirator Protection
Science recognized the need for respiratory protection long ago. The history of respiratory protection dates back to Pliny the Elder (23-79 AD). He was a Roman philosopher and naturalist who used the skin from animal bladders to filter dust from being inhaled while crushing cinnabar. Cinnabar was a toxic, mercuric sulfide mineral used at the time for pigmentation in decorations.
In the 15th century, Leonardo da Vinci recommended wet cloths over the mouth and nose to protect against inhaling harmful agents.
Ancient divers used hoses and tubes to supply air.
Sometime in the 1700s, Bernadino Ramazzini, known as the father of occupational medicine, described the inadequacy of respiratory protection against arsenic, gypsum, lime, tobacco, and silica hazards.
Respirator Protection in the 18th Century and Beyond
In the 18th and 19th centuries, modern respirators were developed. In 1827, the Scottish botanist Robert Brown discovered that collisions of rapidly moving gas molecules cause the random bouncing motion of microscopic particles. Understanding the interactions between the behavior of small particles and the properties of filter media led to the first particulate respirator.
In the 1800s, German scientists studied industrial dust and bacteria and their relationship to respiratory health.
In 1877, the English invented and patented the Nealy Smoke Mask. The mask used a set of water-saturated sponges and a bag of water attached to a neck strap. The wearer could squeeze the bag to re-saturate the sponges to filter out some of the smoke.
In 1920, MSA Safety Company manufactured the Gibbs respirator. This closed-circuit self-contained breathing apparatus (SCBA) is operated on compressed oxygen and a soda lime scrubber to remove carbon dioxide.
Respiratory Protection in the Great War
World War I presented a new threat to soldiers – chemical agents but respirators were not standard issue until World War II. This situation ultimately resulted in 1.3 million casualties and approximately 90,000 fatalities.
Respirator Protection Safety Statistics
In 2017, 41 U.S. workers died on the job after a single episode of inhaling chemicals and chemical products—7 more fatal injuries than in 2016. This number ranged between 33 and 55 fatal injuries each year from 2011 to 2017, with 297 fatalities across the 7-year span.
Inhaling carbon monoxide led to the most fatalities during this period (116 fatal injuries), followed by inhaling hydrogen sulfide (46 fatal injuries)
Of the single-episode fatalities involving chemicals and chemical products, 37 percent occurred in a confined space (110 fatal injuries). All fatal single inhalations of methane gas involved a confined space (9 fatal injuries).
Respirator Protection Safety Tips
Safety Tip #1 Employee Responsibilities
- Employees must wear their respirators when and where required.
- Inform a supervisor if the respirator no longer fits well or new medical conditions arise- this should also trigger a new medical evaluation.
- Use respiratory protection per the manufacturer’s instructions and the training you received.
- Obtain a new respirator when and if needed.
Safety Tip#2: Medical Evaluations
Employees must pass a medical exam before wearing a respirator on the job. Employees are not allowed to wear respirators until a Physician or other Licensed Health Care Professional (PLHCP) has determined that they are medically able to do so.
Safety Tip #3 Fit Testing
Fit testing is a procedure used to determine how well a respirator “fits,” that is, whether the respirator forms a seal on the user’s face. Employees wearing respirators must be fit-tested
- Before using a respirator for the first time.
- After training and medical clearances have been completed.
- Annually thereafter.
Safety Tip #4: Pressure Seal Checks
Employees must conduct user seal checks every time respirators are worn. Use either the positive or negative pressure check (depending on which test works best for you) as specified in the OSHA Respiratory Protection Standard:
- Positive Pressure Test. Perform this test by closing off the exhalation valve with your hand. Breathe air into the mask. The face fit is satisfactory if some pressure can be built up inside the mask without any air leaking out between the mask and the face of the wearer.
- Negative Pressure Test. Perform this test by closing the inlet openings of the cartridge with the palm of your hand. Some masks may require removing the filter holder to seal off the intake valve. Inhale gently so that a vacuum occurs within the face piece. Hold your breath for 10 seconds. The respirator is fitted correctly if the vacuum remains and no inward leakage is detected.
Safety Tip #5: Cleaning
Respirators should be regularly cleaned and disinfected. When cleaning and disinfecting reusable respirators, do the following:
Disassemble the respirator, removing any filters, canisters, or cartridges.
Wash the face piece and all associated parts (except cartridges and elastic headbands). Use warm water (about 120 degrees Fahrenheit) and an approved disinfectant. Do not use organic solvents. Use a hand brush to remove dirt.
Rinse entirely in clean, warm water.
Disinfect all facial contact areas by spraying the respirator with an approved disinfectant or using disinfectant wipes.
Air dry in a clean area.
Reassemble the respirator and replace any defective parts.
Insert new filters or cartridges and make sure the seal is tight.
Test the respirator to ensure that all components work properly.
Place the respirator in a clean, dry plastic bag or other airtight container.
Safety Tip #6 Maintenance and Inspection
Maintain respirators to ensure that they function correctly. Replace worn or deteriorated parts before use. No components should be replaced or repairs made beyond those recommended by the manufacturer. Inspect respirators before and after each use.
Check for overall respirator function and the tightness of connections. Check the following items during an inspection:
Facepiece. Examine the face piece for cracks, tears, holes, face mask distortion, and cracked or loose lenses/face shields.
Head straps. Examine head straps for breaks or tears and broken buckles/connectors.
Valves. Examine valves for residue or dirt, cracks or tears in valve material.
Filters/Cartridges. Examine filters/cartridges for approval designation (i.e., proper cartridge for the hazard), gaskets, cracks, or dents in housing.
Supplied Air Systems. Confirm breathing air quality is at least Grade D for supplied air respirators, and examine the condition of the supply hoses, hose connections, and the settings on the regulators, valves, and alarms.
Elastomeric parts. Examine elastomeric parts for pliability and signs of deterioration.
Safety Tip #7 Malfunctions and Defects
For any malfunction of an ASR (atmosphere-supplying respirator), such as breakthrough, face piece leakage, or improperly working valve, the wearer should inform their supervisor and go to a designated safe area to maintain the respirator.
Safety Tip #8 Storage
After inspection, cleaning, and necessary repairs, respirators shall be stored appropriately to protect against dust, sunlight, heat, extreme cold, excessive moisture, or damaging chemicals.
Safety Tip #9 Training
Employees must be trained before using a respirator.
Training should include:
The site-specific Company Respiratory Protection Program.
OSHA’s Respiratory Protection Standard.
Workplace respiratory hazards encountered and their health effects.
Proper selection and use of respirators.
Limitations of respirators.
Respirator donning and user seal (fit) checks.
Fit testing.
Emergency use procedures.
Maintenance and storage.
Medical signs and symptoms limiting the effective use of respirators.
Safety Tip #10 Cartridge Change-out Schedule
Cartridges in air purifying respirators remove chemical contaminants before the air enters the breathing zone. These cartridges work by an absorption process—contaminants in the air are attracted to the media in the filter. Since there is a limited amount of media in the cartridges, it has a limited service life and has to be changed when the media becomes nearly spent. The service life of a cartridge depends on several factors, including environmental conditions, breathing rate, cartridge filtering capacity, and the amount of contaminants in the air.
Always follow your company’s written respirator program requirement for cartridge change-out.
In the event of a breakthrough, meaning the cartridge or filter becomes soiled, or breathing becomes difficult before the scheduled change-out interval, the cartridge/filter should be changed immediately. Also, notify your supervisor immediately, use conditions may need to be re-evaluated and adjustments made to the change schedule.
Sources:
https://www.cdc.gov/niosh/npptl/Respiratory-Protection-history.html
https://www.bls.gov/opub/ted/2019/fatal-chemical-inhalations-in-the-workplace-up-in-2017.htm