Document vBXq72X5ZDpZYq2y7Q7od24M8

4. The location of the hazard area with re spect to a source of uncontaminated res pirable air, 5 The state of health of personnel involved, 6 The functional and physical characteristics of respiratory protective devices The safety professional should familiarize himself with the type of hazard for which a given type of respiratory equipment is ap proved, and should not permit its use for protection against hazards for which it is not designed For instance, particulate filter respirators are of no value as protection against solvent vapors, injurious gases, or lack of oxygen Their use under these condi tions is one of the most common and most dangerous abuses of respirators Oher common misuses of respiratory equip ment are to use chemical cartridge respirators where gas masks are required or to use chem ical filtering types where atmosphere-support ing or self-contained units are necessary Some substances require protection against (a) damage to the respiratory system, and also (b) systemic injury through the skm All substances should be investigated to learn whether this double hazard is involved Some common substances which are hazardous through both the respiratory system and the skm are Aniline Carbon disulfide Cresol (cresyhc acid) Dichloroethylene-1,1 Decahn (decahydronaphthalene) Diethylene oxide (dioxane-1,4) Diethylphthalate Dimethylamhne Dinitrobenzene Dimtrochlorobenzene Hydrogen cyanide (hydrocyanic acid) Iodoform Lead tetraethyl Mercury and its compounds Nicotine Nitrobenzene Nitroglycerine Organic phosphate insecticides Phenyl hydrazine Tetrahn (tetrahydronaphthalene) See Chapter 39, "Chemical Hazards," for a full list Some workers consider respiratory equip ment a nuisance, not realizing that failure to wear it may endanger their lives Usually, the attitude of such men can be changed if someone in authority will clearly explain why the equipment is necessary, show the men how to fit it in position, and explam its opera tion If such educational efforts fail, the alternative is discipline, for the risk of injury is senous Excellent health and thorough training m the operation and maintenance of equipment are essential for persons who are to use re spiratory protective devices Anyone in questionable physical condition should be prevented from entering environments pre senting respiratory hazards, and thus avoid having to wear any emergency breathing apparatus for protection From the standpoint of fire hazard, neither pure oxygen nor air containing more than 21 percent oxygen is to be preferred to ordinary air for use in atmosphere (air) supplied respi rators or open-circuit (demand) type selfcontained breathing apparatus, for ventilating, or for other purposes A flammable substance in the presence of oxygen requires only a small fraction of the energy to ignite it as does the same substance in the presence of air, and an ensuing fire or explosion is much more violent Air or oxygen provided by or supplied to any respiratory equipment must be free from contaminants, quality as well as quantity is important Respirable air should comply with the Compressed Gas Association Commodity Specification for Air, G-71-1966 (ANSI Z861), Grade D This specifies that the maximum impurities be as follows condensed hydrocarbons, 5 mg/m3 of gas at NTP, carbon monoxide, 10 mg/m3, and carbon dioxide, 1000 mg/m3 The presence of a pronounced odor renders the air unsatisfactory for breath ing The standard gives methods of verifica tion and other details Oxygen should meet the requirements of the United States Pharmacopoeia Respiratory protective devices can be clas sified as follows 1 Air purifying respirators. 491