6.1.1    

All hazardous chemicals have a maximum concentration set by OSHA (Example:  Ammonia is   35 ppm on STEL short term exposure lim it) that is 15 minute time weighted average exposure during a work day).

6.1.2    

Respirators are needed while engineering controls are being instituted or if these controls are not working.  (Example: if local ventilation fails and air contaminants go over allowable limits).

6.1.3    

Respirators are required for temporary exposure to high concentrations of toxic substances such as during maintenance or repair or in an emergency.

6.1.4    

Respirators are required for oxygen deficient atmosphere such as in confined spaces.

7.1.1    

DenisonUniversity shall provide the proper the proper respirator for the particular hazard and shall establish a respiratory protection program.  This is to be done by Denison University Physical plant supervision.

7.1.2    

DenisonUniversity should designate a responsible person to administer the respiratory protection program.

7.1.3    

Requirement of an acceptable program:

1. Written standard operating procedures detailing the selection and use of respirators shall be established.
2. Respirators shall be selected based upon the hazard to which the worker is exposed.
3. The user shall be instructed and trained in the proper use of the respirator and their limitations.
4. Respirators, where applicable, should be assigned to individual workers for their exclusive use.
5. Respirators shall be regularly cleaned and disinfected.
   1. Single user:  cleaned after each days' use, or more often if necessary.
   2. multiple users:  thoroughly cleaned and disinfected after each days' use.
6. Respirators shall be stored in a convenient, clean and sanitary location.
7. Appropriate surveillance of work area conditions and degree of employee exposure or stress shall be maintained.  This is to be done by the maintenance supervisor.
8. There shall be regular inspection and evaluation to determine the continued effectiveness of the program.  Written records will be kept by the maintenance supervisor.
9. Persons should not be assigned to tasks requiring use of respirators unless it has been determined that they are physically able to perform the work and use the equipment.

7.2.1    

Identification of Hazard

1. Choice of respirator is dependent upon the type, concentration and warning properties of the contaminant.  If there are no over-exposures, there is no need for respirators.
2. Respirators may be needed to control exposures to non-regulated, in-house substances.
3. Types of hazards:
   1. Gaseous:  gaseous hazards are formless and often colorless fluids.  There are two different types of gaseous hazards.
      1. These are substances which are gases at normal room temperature.  Gases are only liquid or solid at much lower temperatures or higher pressures than are found in the typical industrial environment.  Examples include chlorine and methane.
      2. Vapors:  a gaseous substance formed by the evaporation of a liquid.  Vapors are ordinarily liquid at room temperature.  Examples include the vapors of solvents such as trichloroethylene.
   2. particulate:  this type of hazard is comprised of tiny particles or droplets.  There are three types of particulate hazards:
   3. 1. Dusts:  comprised of tiny solid particles produced by such processes as grinding, crushing and mixing of powder compounds.  Examples include sand and plaster dust.
      2. Mists:  comprised of tiny droplets of liquid.  Forms when liquid is sprayed vigorously mixed or otherwise agitated.  Examples include acid mists from plating operations and oil mists from machine shops.
      3. Fumes:  comprised of solid condensation particles of extremely small size which are formed from heated metal vapor.  Examples include fumes from processes such as soldering, brazing, welding, molding or casting of metal.
   4. Combination:  this type of hazard is a combination of the particulate and gaseous contaminates.  All example of this type of hazard would be found in paint spraying where a vapor and a mist are formed.
   5. Oxygen deficient atmospheres:  this type of hazard does not include the presence of any hazardous contaminate.  Instead, this hazard is comprised of the absence of a material essential to life - oxygen.  Normal air contains approximately 21% oxygen.  Decreasing this percentage below 19% places a stress on the pulmonary and cardiovascular systems as well as the central nervous system and can eventually lead to death.  This type of hazard is most often associated with confined space entry or poorly ventilated areas and is considered immediately dangerous to life and health (IDLH).  There are two ways by which the oxygen may be depleted.
      1. The oxygen may be used up in a chemical reaction such as fires or the formation of rust.
      2. The oxygen may be displaced by another gas.
   6. Immediately dangerous to life and health (IDLH):  this type of hazard presents the possibility of serious injury or death occurring. There are two examples:
      1. Serious injury or death occurring within a short time due to exposure to high concentrations of a hazardous substance such as carbon monoxide or hydrogen sulfide.
      2. Serious delayed effects caused by exposure to low concentrations of radioactive or cancer-causing agents.

7.2.2    

Evaluation of the Hazard:  includes a walk-through of the entire job site to identify and quantify the hazardous substances and conditions requiring respiratory protection.  This is to be done by the maintenance supervisor.

7.2.3    

Purchase of Respiratory Equipment

1. The program administrator and maintenance supervisor should have complete authority to approve the purchase of respiratory equipment.
2. All respiratory equipment purchased must be approved for the particular contaminant.
   1. All respirators must contain the NIOSH or NIOSH/MSHA approval.
   2. Properly approved respirators contain the following:
      1. An identification number on each unit such as TC-21C-101.
      2. A label identifying the type of hazard the respirator is approved to protect against.
      3. Any additional information relating to the limitations of the respirator and identification of component parts approved for use with the respirator.

7.3.1    

Workers should not be assigned to tasks requiring the use of respirators unless they have been found medically and physically capable of wearing the equipment.

7.3.2    

Two types of Stress Related to Respirators

1. Psychological:  some people who suffer claustrophobia may be unable to wear a respirator.
2. Physiological:
   1. Negative pressure respirators make breathing more difficult because the filter or cartridge impedes air flow.
   2. Open-circuit, pressure-demand respirators require exhalation against significant resistance.
   3. The weight and bulk of self-contained breathing apparatus (SCBA) and air-line respirators may cause a burden.
   4. medical conditions that may be aggravated by the wearing of a respirator include:
      1. asthma or emphysema
      2. difficulty with breathing
      3. previously documented lung ailment
      4. high blood pressure
      5. arterial diseases
      6. documented heart problems
      7. missing or arthritic fingers
      8. facial scars
      9. poor eyesight
      10. claustrophobia

7.4.1    

Air Purifying

1. Negative pressure respirators work by drawing air through cartridges as the person inhales.  As the person exhales, air is released through a valve in the face piece.  It is extremely important that the respirator fit properly.  If the respirator does not completely seal, the contaminant can enter around the edge of the face piece as the person inhales.
2. Powered air purifying respirators (PAPR) utilize a pump to draw air through cartridges and then supply the clean air to the breathing zone.  Proper utilization of the PAPR greatly decreases the chance of a person being exposed to contaminants.
3. Cartridges:  there are two basic types of cartridges used for air purifying respirators:
   1. Cartridges which contain filters are utilized for removal of particulate (fume, mist and dust) contaminants.  Air is drawn through the filter and particles are trapped on the filter.  As more particles are collected on the filter, the filter becomes more efficient.  However, it also becomes harder to draw air through the filter.  A lot of resistance upon inhalation is an indication that the filter needs changing.  Filters are useless against vapors and gases because the pore size is too large.
   2. Cartridges which contain an absorbent or a chemical are used to remove gases and vapors.  As air is drawn through the cartridge, the contaminant is trapped by the absorbent (generally activated carbon) or reacted with the chemical.  These types of cartridges are used only in atmospheres where the contaminant has sufficient warning properties (a taste, irritation or odor at contaminant concentrations below the permissible exposure limit that would warn the individual when the cartridge is overloaded).
   3. There are also cartridges made which are used to remove a combination of particles and gases, mists and vapors.
4. Face piece Styles
   1. Quarter mask:  covers from the bridge of the nose to just below the lower lip.
   2. Half mask:  covers from the bridge of the nose and to below the chin.
   3. Full face piece:  covers the entire face, providing protection against eye irritation as well as respiratory protection.

7.4.2    

Atmosphere Supplying

1. Supplied-air or air-line respirators utilize a hose that supplies air from a compressor or compressed air tank to the face piece.  Exhaled hair is released through a valve or openings in the face piece.  There are four different regulator types:
   1. Continuous-Flow:  air flows constantly to the face piece, maintaining a positive pressure in the face piece.  The air is also supplied at a constant pressure (4 cubic feet per minute (CFM) for tight-fitting face pieces and 6 CFM for loose-fitting face pieces).
   2. Demand:  air flows to the face pieces only during inhalation.  Potential leakage problems due to slight negative pressure that develops in the mask.
   3. Pressure Demand:  provides air to the face piece on demand and keeps the mask under positive pressure at all times.
   4. Combination:  switchable between demand and pressure demand.
2. Self-contained breathing apparatus (SCBA) utilize portable compressed air tanks to supply air to the face piece.  An SCBA can be operated in either a demand mode or a pressure demand mode.  There are two types of SCBA:
   1. Closed-Circuit:  in this type of system, exhaled air is re-circulated through a carbon dioxide-removing chemical, mixed with oxygen and sent back to the face piece.
   2. Open-Circuit:  in this system, the exhaled air is released through a valve to the atmosphere.

7.5.1    

Wearing An Air Purifying Respirator

Respirators come in a variety of sizes.  The employee should try to select a face piece size that is relatively comfortable but will produce the best face to face piece seal.  A quarter mask respirator should cover the mouth and nose; the half mask should fit over the nose and under the chin.  Full face piece respirators should cover the face from the hairline to below the chin.

7.5.2    

Donning Procedure For An Air Purifying Respirator

1. Place face piece over bridge of nose with exhalation valve under chin.  (1/4 mask will not fit under the chin but will fit under the lower lip)
2. Engage upper headband above the face.
3. Attach lower headband behind the neck and below the ears.
4. Adjust straps for fit and comfort.

The face piece of the respirator should sit as low as possible on the bridge of the nose to avoid obstructing view.  Once the on the bridge of the nose to avoid obstructing view.  Once the straps have been adjusted, ensure that the respirator is properly seated.  There should not be any up and down movement of the respirator.  Turning your head from side to side should not cause the respirator to move.

7.6.1    

Cleaning the Respirator

The respirator standard requires that respirators be regularly cleaned and disinfected.  Those issued for the use of a single cleaned and disinfected.  Those issued for the use of a single worker should be cleaned after each use, or more often if necessary.  Disinfection is particularly important when more than one employee is using the same respirator.  Two tablespoons of bleach to one gallon of water makes a good, cheap disinfecting solution.  Quaternary ammonium compounds may also be used for disinfection purposes.  Disassemble respirator components and soak for two minutes.  Do not soak respirator cartridge(s), canister(s) or filter(s).  Rinse components in clean water and then allow the respirator to dry in a designated area.  Reassemble the respirator after it is dry.

7.6.2    

Inspecting the Respirator

The standard requires that respirators that are used frequently be inspected during cleaning.  Worn, defective or damaged parts shall be reported to the maintenance supervisor.  The wearer should check the following components of an air purifying respirator.

1. Exhalation and inhalation ports:  check threads for wear.  If threads are worn, cartridges will not attach to the face piece properly.
2. Exhalation and inhalation valves:  these thin, flexible parts are subject to wear and tear.  Check valves for tears, deterioration, soap scum, dirt and anything else that would affect the valves' ability to seal properly.
3. Protective exhalation port cover:  check threads for wear.
4. Upper and lower headband:  check straps for elasticity.  Worn straps will cause the respirator to not seal properly.
5. Face piece:  the face piece is made of a soft, flexible material such as silicon rubber.  Check for cracks or tears in the face piece.  Stretching and manipulating rubber parts (the face piece) with a massaging action will keep them pliable and flexible and prevent them from taking a "set" during storage.

Respirators for emergency use, such as self-contained devices, shall be thoroughly inspected at least once a month and after each use.  Air and oxygen cylinder shall be fully charged.  Regulator and warning devices shall be checked to see that they are functioning properly.  The monthly inspection should include a visual check of the face piece assembly, breathing tube, head harness and exhalation valve for worn or damaged components.  This will be done and recorded monthly by the maintenance supervisor.

7.6.3    

Repairing the Respirator

1. Most parts of the respirator are replaceable.  Replacing the parts of an air purifying respirator should not present any problems.  The replacement part must be exactly the same (type, size, manufacturer, etc.) as the part being replaced.  Substitution of parts from a different brand or type of respirator invalidates the approval of the respirator.
2. Air supplying respirators, with the exception of the SCBA, can be repaired if parts are replaced by a qualified individual with the aid of the manufacturer's literature.
3. Maintenance of SCBA equipment is more difficult due primarily to the valve and regulator assembly.  The standard required that reducing or admission valves or regulators be returned to the manufacturer or to a trained technician for adjustment or repair.

7.6.4    

Storing the Respirator

After cleaning, inspection and necessary repair, respirators shall be stored to protect against dust, sunlight, heat, extreme cold, excessive moisture or damaging chemicals.  Routinely used respirators, such as dust respirators, may be placed in plastic bags.  Respirators should not be placed in lockers or tool boxes unless they are in carrying cases or cartons.  Respirators should be packed or stored so that the face piece and exhalation valve rest in a normal position so their function will not be impaired by the elastomer setting in an abnormal position.