Respiratory Protection Flashcards
Fumes
occur during high heat operations such as welding or smelting
hazarads such as painting or pesticide applications or liquids are set in motion in the air
gasses are usually produced such as a chemical process such as hydrogen sulfide found in sewers storm drains
carbon monoxide gas is a byproduct of engine exhaust
some have odors some do not
hydrogen sulfide smells like rotten eggs
carbon monoxide is odorless and has no color
vapors are the products of volatile liquids giving off vapors such as gasoline, paint, or solvents
oxygen deficiency a lack of oxygen in an area where you are working such as confined spaces
Protection from Respiratory Hazards
joint cooperation from the ER and EE>
ER has the responsibility to determine and reduce or remove the hazards of the job - ER also provides the protective equipment
EE has the responsibility to follow the company’s policies and procedures
29 CFR 1910.134
OSHA requires ER to have a respiratory protection program covering all ee’s whose job requires the use of respirators
1. respirators are selected based on hazards to which the EE is exposed
2. user is to be trained and instructed in the proper use and limitations
3. written procedures must be established
4. must be regularly cleaned and disinfected
5. used routinely must be inspected when cleaning and worn or deteriorated parts are to be replaced
6 stored in a convenient clean and sanitary location
7.appropriate survelance of work area conditions and degree of ee should be maintained
8. user properly fit tested and taught how to check face piece fit before each use
9. er should determine if a user can perform the work use the equipment and be reviewed periodically when conditions change and supervisor recommends PLHCP evaluation
10 effectiveness of the program should be evaluated on a regular basis
Selection of respiratory equipment
respiratiory protection is of primary importance since inhalation is the main exposure to chemical toxicants.
protectitave devices consist of a face piece connected to an air source or an air purifying devise
Positive and Negatice Air Flow
Different types of airflow may influence the selection of a respirator.
positive pressure air flow
negative pressure air flow
positive pressure air flow
respiratior maintaing a positive pressure face piece during both inhalation and exhalation .
2 types of positive pressure air flow respirators:
pressure demand -
and continuous flow
Pressure demand
a pressue regulator and an exhalation valce on the mask maintains the masks positive pressure except during high breathing rates . if a leak develops in the regulator sends a flow of clean air into the face piece preventing penetration by contaminated ambient air.
Continuous Flow Respirators
including some supply respirators SARS including All powered respirators PAPR send a continuous flow of air into the face piece at all times.
with SARs the continuous flow of air iprevents infiltration invasion into ambient air. but uses the air supp;ly more rapidly than air that with pressure demant respirators.
our air purifying air respirators PAPRs are operatied in a positive pressure mode utilizing filtered ambient air. However maximum that is highest breathing rates can create negative pressure in the facepiece of a PAPR
Negative pressure respirators draw air into the face piece via the negative pressure created by user inhalation. the main disadvantage of negative pressure respirators that is if a leak or a crack in the hose or an illfitting mask or the face piece the user draws contaminated air into the facepiece during inhalation. when atmosthere supply respirators are used only those operated in the positive pressure mode are recommended for work at hazardous waste sites.
Atmosphere supplying respirators
with an air source or consist of 2 types
2 types
self contained breathing appartus SCBA
supplied Air respirator SAR
supplies with an airline hose
sometimes referred to as airline respinratos
Air purigying respiratior APRs
do not have a separate air source they utilize ambient sorrounding air that is purified with a filter before inhalation
Types of face pieces
Different types are available for use with various types of respirators
the types generally used at hazardous work sites are
Full face masks cover the hairline to below the chin protecting the eyes
Half masks from the nose to below the chin
Testing
tested an approved by Mine Safety and Health Administration MSHA and NIOSH
29 CFR 1910.134 Appendix a has the regulations
approved numbers are on all equipment
not all respiratory equipment sold is approved
NIOSH has a list of approved respirators and components
Protection Factor
the level of protection that can be provided by a respirator is indicated by the respirator’s protection factor. The assigned protection factor APF is determined experimentally by measuring face piece seal and measured and teh exhalation valve leakage
the number indicates the relative difference between
outside and inside the facepiece. is 50 is the protection factor - workers wearing these respirators can be protected in atmospheres containing chemicals at concentrations that are 50 X greater than the appropriate limits - PEL TLVs
refered to as the maximum use limit MUL one source of protection factors for various types of atmosphere SCBA and SAR and air purifying respiratiors can be found in american national Standards Institure ANSI.Z88.2 1980
Sites with concentration of chemicals
At sites where the Identity and concentration of the chemicals in the air are known a respirator should be selected with a protection factor that is sufficiently high so they do not go over the limits
these limits in clude -
American Conference of Governmental and Industrial Limits - TLVs
OSHA’s limits PELs
NISHA limits RELs
Limits
These limits are designed to protect these workers exposed to chemicals day after day throughout their working lifes
OSHA PELS are legally enforcable exposuer limits has the minimum protection that must be met.
If a worker has a high breathing rate
Ambient temperature is high or low
most notably if a worker has
If a worker has a poor face piece to face seal
Addtitional breathing ingomato
At high breathing rates positive pressure scba and sarr;s
may not maintain pressure for brief
at high work rates may leak consequently
poritive preoffer less prote
High Breathing Rates
positive pressure SCBAs and SARs may not maintain positive pressure during peak inhilation.
at high work rates exhalation valves may leak.
Positive pressure respirators working at high flow rates offer less protection than when working at normal rates.
Air purifying respirators
APRs consist of a facepiece and an air-purifying device. the device is a removable component of the face piece or an apparatus worn on a body harness and attached to the face piece by a corrugated hose.
APR specifically removes specific airborne contaminants and (particulates gasses vapors and fumes ) from ambient air by filtration aborbtion by chemical reactions
Respirators that are clogged
Respirator Clogged with trapped particles. It becomes difficult to breathe or allows odors to enter the breathing zone. When that happens it is time to change the respirator or cartridge. 1/2 mask are designed to cover mouth nose and chin. replacable cartridges that Trap dust mist or vapors entering the breathing zone. Each cartridge has a specific filter for each chemical and some cartridges can protect against several hazards. May have a pre filter that traps additional dust and fumes. Selection of the proper mask is important.
Know the hazard then select the proper protection.
the half-mask respirator is a rubber or Silicone mask with 2 to 3 valves. one valve lets air out and the other lets air in. The entire mask must be inspected before use. check the rubber silicone parts to make sure they are not valves to ensure they are clean, not missing, brittle or broken. 1/2 masks do not protect from oxygen deficiency nor does it protect from what is not written on the cartridge label.
APRs
are used in atmospheres containing specific chemicals up to designated concentrations. are not approved for IDLH immediately dangerous for life and health atmospheres.
limited uses at wate sites and can be used when the ambient atmosphere contains sufficient oxygen that is
greater than 19.5 30 CFR part 11.90A
operate only in the negative pressure mode except for powered air purifying respirators which maintain a positive pressure except at PAPRs except at maximum breathing rates.
3 types of air purifying devices
1. particulate filters
2. cartridges and cannisters which contain
3. combination devices
Cartridges
attach to the respirator facepiece. larger volume canisters attach to the chin of the facepiece or are carried with the harness and attached to the facepiece with a breathing tube. maximum use concentrations MUC or in the package where the cartridge is sealed.
Combination cannisters and cartridges
combination cannisters and cartridges have layers of different sorbent materials and remove multiple chemicals from the ambient air. approved for more than 1 substance they are tested independently against single substances. the effectiveness of more than 2 substances has not been demonstrated.
Filters can be combined with cartridges to give additional protection against particulates. A number of standard cartridges and cannisters are available. They are color coded to show which chemicals or classes of chemicals against which they are effective. 29 CFR 1910.134G
Respirators
used Only for the substances for which they are approved. For a limited number of chemicals, MSHA and NIOSH have granted approvals for manufacturers specific assemblies of air purifying respirators. performed at a given temperature and over a narrow range of flow rates and humidity levels . Thus the equipment can be compromised in nonstandard conditons.
The assembly approved by MSHA and NIOSH to protect against organic vapors is testing is tested against only one single challenge substance - carbon tetrachloride. Therefore the assembly’s effectiveness in protecting against other vapors has not been demonstrated.
The efficacy of APR’s varies widely even on closely related substances. Use of a sorbent shall not be allowed when it does not provide adequate sorbtion efficiency against a specific contaminant.
Adequate warning properties
If a cannister or cartridge is to be used against gases or vapors the appropriate devise is to be used only if the chemicals have adequate warning properties 30 CFR Part 11.150.
NIOSH considers a substance to have adequate warning properties when:
- odor tase and irritant properties are detectable and persistent concentrations below the permissable exposure limit
poor warning properties when
- its odor or irritation threshhold or applicable properties is above the exposure limit.
Sorbent Exhaustion
Respiratory standard emphasizes Contaminant breakthrough should not be relied on as a signal or an indicator of sorbent exhaustion.
Cannistors or cartridges should be changed out in accordance with a change schedule. Change schedules can be obtained through the OSHA website, manufacturers shedules and trade associations.
if these are not applicable then according to the company’s policy.
OSHA permits the use of air purifying respirators for protection against specific chemicals with poor warning properties provided that one of the following is true.
- the surface life of the sorbent is known and a safety factor is applied
- the respirator has an approved surface life indicator
chemical absorbent cannisters
sorbent canisters are imprented with an expiration date. they can be use up to that date as long as they are not previously opened. Once opened they absorb humidity or air contaminants when not in use.
since efficiency and service life decrease they should be used immediately. cartridges should not be used for more than 1 shift after breakthrough (detection of the chemical through odor, taste or irritation effects) cartridges should be discarded after use.
Self contained breathing apparatus
SCBA facepiece connected by a hose, a regulatorconnected to an air source (compressed air, compressed oxygen and and oxygenated chemical) carried by the wearer.