SECTION 14. SELECTION & USE OF RESPIRATORS

14.1 GENERAL

The types of respirators in use at APO are half-face, full face, and mask-style filter types. Safety goggles are available for operations that cause eye irritation or the risk of eye injury from flying objects. These respirators DO NOT supply oxygen. The available oxygen in the room is all that is available to breath. The observatory does not maintain Self Contained Breathing Apparatus (SCBA) for use and, consequently, materials that require them cannot be used.

Normal room atmosphere contains approximately 21% oxygen; the rest of the air is made up of nitrogen, carbon dioxide, and in lesser quantities various other gases. The human body requires at least 16% oxygen concentration for proper operation. Due to the altitude of APO, this concentration is even more critical due to the lower vapor pressure. It is important to realize these respirators do nothing to add to the available oxygen you breath. If the oxygen level is reduced due to displacement from other gases then there may not be enough to sustain your work activity or life. For most of our operations this means an open door/window, at a minimum, or forced air circulation using intake/exhaust fans is required. A respirator is no substitute for adequate ventilation. Whenever possible chose adequate ventilation over using a respirator.

14.2 EMERGENCIES

If the oxygen level is reduced certain physiological reactions will take place. It is important that you be able to recognize these symptoms in both yourself and in co-workers. These are only some of the symptoms that may be present. Individuals may react differently and not all symptoms will be noticeable.

Some of the signs of hypoxia (low oxygen) are: fatigue, headache, dizziness, breathing difficulties, confusion, and loss of consciousness. In the event you or someone else experiences any of these symptoms they must be removed from the contaminated area and given an immediate supply of fresh air. If in doubt, or supplemental oxygen is required, contact the Otero County Sheriff’s office (911), and ask for Sunspot EMS to respond. If someone is unconscious in a contaminated atmosphere and immediate forced ventilation is not possible, do not attempt to remove them yourself. Contact the Otero County Sheriff’s office (911) and ask for Sunspot Fire and EMS to respond.

Oxygen monitors used for confined spaces may be used to monitor oxygen levels where respirators are required.

14.3 SELECTION

Respirator selection is one of the most important aspects of using a respirator. You must check the type of respirator cartridge against the requirements of the MSDS and the manufacturers recommendations.

These filters can be used in tandem to provide proper filter performance in combined environments.

Respirators are used for several different purposes and your decision to use a respirator or not is crucial and determines the procedures you must follow. Generally, housekeeping staff and maintenance personnel may use a particulate mask to avoid breathing in certain dust and certain dust-related particles. The observatory is kept clean and housekeeping is done on a regular basis to avoid large-scale build up. However occasionally spots may be uncovered that will have larger than normal accumulation. HEPA-style particulate masks may be used for this work.

On occasion, personnel will use solvents for cleaning. This cleaning could be anything from paint/gum residue to CCD dewars. The best courses of action during all of these operations are good work habits, conservation, and ventilation to limit the exposure. Since there are no routine operations, it is impossible to know in advance if you will exceed the limits for a specific substance. Consequently, monitoring at the location is desired if a respirator is not used, except in places with very good ventilation. APO maintains VOC monitors for area monitoring for certain substances and may eliminate the need for use of a respirator.

14.3A PRIOR TO USE

The NMSU safety office provides fit testing and medical evaluations for required respirator wearers. You must contact the safety office for these services before using a respirator for other than for dust particles. These evaluations must be done on a periodic basis and can be scheduled through the safety office. The training provided during these sessions will address proper fit, as well as pre- and post-inspection and cleaning. Medical certification will be required prior to receiving this training. Facial hair that interferes with the operation of the mask will be cause for de-certification. Thus once certified the employee must maintain a similar shaven appearance or be de-certified. Visitors and contractors must supply proof of certification and their own respirators.

Personnel using respirators on a voluntary basis will be provided a copy of Appendix D to 1910.134, OSHA Industrial Standards. Personnel must read and understand this prior to use. (http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9784)

14.4 USE

A respirator should be used wherever specified by the MSDS, ventilation is questionable, noticeable particulate are present, or any irritation of the skin, eyes, throat, or nose exist. These respirators are not sufficient for use when oxygen concentration is less than 19.5%, or the local atmosphere is an immediate danger to life or health. Besides having different filter properties, the types of filters function differently.

An absorption filter works by the vapors passing through the cartridge are attracted and held in by the surface of the carbon. Acid gases are either absorbed or a chemical reaction takes place. These cartridges lose efficiency with time and use. Their absorption capacity is limited and once any odor, taste, or irritation is sensed the wearer must leave the contaminated area and replace the filter cartridge. Organic filters should only be used once then discarded.

A mechanical filter element traps particles due to their size in relation to the size of the porous filter material. These filters increase in efficiency with use. However, breathing resistance will also increase. If this becomes noticeable, the filter element should be replaced.

14.5 MAINTENANCE, CLEANING & STORAGE

Respirators are provided and assigned to each individual that has been certified to use them. The individual is responsible for the storage, cleanliness and the security of their respirator and associated cartridges.

After each use, the respirator will be cleaned and disinfected using the kit provided. This provides ready use for the next time. Once cleaned, the respirator should be placed in a clean bag and sealed. This will protect the respirator from atmospheric contamination while sitting on the shelf and serve as a sign that the respirator is ready for use.

Disposable dust particle masks are provided and shall be discarded after use. They are not to be restocked or used by more than one person.

Cartridges shall be changed in-accordance with manufacturer’s recommendations. The certified user shall be responsible for changing out their cartridges as required.

14.6 INSPECTION

Once a year the respirators will be inspected by those certified to wear them for cleanliness, function, and defects. The inspection will consist of checks for tightness of connections, headbands, and canisters. The rubber and elastic parts will be checked for pliability, deterioration, and deformity. Filters will be checked for cleanliness and, if build up is noticeable, the filters will be replaced. An inventory check of replacement elements will also be accomplished. Respirators should be taken and used during the annual re-certification to ensure this is accomplished.

14.7 WORK REQUIREMENT

Respirators are required for the following routine operations:

1. Servicing the main azimuth bearings on the 2.5m and 3.5m Telescopes

- unless adequate ventilation is achieved, or
- due to large amounts of solvents required.