Respirator air-line

Is positive pressure self-contained breathing apparatus (SCBA) or positive pressure air-line respirator and escape air supply used when chemical exposure will create a substantial possibility of immediate death, immediate serious illness or injury, or impair the ability to escape ... 

Goggles, impervious gloves, protective clothes and shoes are recommended. Chemical cartridge respirators are sufficient for routine handling. Air-line respirators or self-contained breathing apparatus are recommended for high concentrations. 

Location of the hazard area. Air supply for a hose mask or air line respirator requires a source of clean, uncontaminated air within the distance limits of the air hose, that is, 300 feet for a hose with an attached air blower and 75 feet without a blower. Obviously, before selecting a respirator of that type, the source of clean air should be identified. 

Respiratory protective equipment can be divided into two broad categories air purifying and air supplying devices. Air purifying devices are items such as dust masks, chemical cartridge respirators, and gas masks. The air supplying devices are hose masks, air line respirators, and self-contained apparatus. 

Cartridge respirators are also not suitable for use in firefighting and sandblasting as well as in atmospheres containing less than the normal 21 percent of oxygen or where the concentration of the contaminants is unknown or immediately threatening to life. In these unsuitable situations, an air line respirator or a self-contained apparatus (see following) should be used. 

Air line respirators are similar to hose respirators, except that they are supplied with compressed air from a clean air source and compressor. They provide complete protection, and because they offer little in the way of breathing resistance, they are more suitable than hose respirators for prolonged use. There are two basic types continuous flow and demand flow. 

Air-line Respirators These are respirators similar to SCBA except that the unit is connected to a hose that can be deployed to a maximum distance of 300 feet. These respirators can only be used in IDLH atmospheres when they are equipped with an escape air supply that can provide breathing air for at least 5 minutes. This limitation is necessary because most air-line respirators are entirely dependent upon an air supply that is not carried by the wearer of the respirator. 

Trichlorofluoro- methane Air-line respirator, rubber gloves, monogoggles. Move victim to fresh air and if necessary apply artificial respiration and/or administer oxygen. Call physician immediately. If frostbite has occurred, flush areas with warm water. ... 

Combination of air-line respirator and auxiliary self- contained air supply or air-storage receiver with alarm Self-contained breathing apparatus Hose mask with blower... 

Figure 6.40 shows a typical use situation and the different elements of a fresh-air suction air line respirator. 

Fresh-air compressed air line respirators do not differ much from fresh-air suction air line devices. The breathing air, which is taken from an uncontaminated environment, is propelled by a powered or hand-driven fresh-air blower having a slight over-pressure. Any excess air, which is necessary in the case of helmets or hoods, can escape into the environment via a control valve. A minimum volume flow of 300 L min air has to be guaranteed. Besides the use of fresh compressed... 

In combination with a full-face mask, their use is possible in a contaminated atmosphere containing up to 1000 times the OEL, but with a half mask up to 100 times the OEL only. If the requirements according to EN 269 [6-83] are fulfilled, a fresh-air helmet or hood can be used up to 100 times the OEL. If warning devices indicating weakness or breakdown of the air supply are not present, the use of air line respirators is not allowed for protection against carcinogens, very toxic or radioactive substances, or micro-organisms and enzymes (see Table 6.29). 

For paint spraying, compressed air line respirators are commonly used in a special light version - so-called light duty air line respirators (see Fig. 6.41). Depending on the overall leakage, they are divided into 3 classes. Respective maximum allowable concentrations are given in Table 6.31. These respiratory hoods should not be used for work other than paint spraying. 

Air-line respirators and SCBA units can also be used to enter atmospheres contaminated with fluorine and carbon monoxide. However, full hoods of inert materials such as Teflon or KelF must be used to avoid skin contact with fluorine these materials can also be used to protect the rest of the body. 

As noted in Chapter 2, the minimum allowable oxygen concentration in an oxygen-deficient atmosphere depends on the nature of the diluting gas. Thus, because of the peculiar role of carbon dioxide in the respiratory functions of the body, the oxygen concentration in the atmosphere must not drop below 19 vol. % this corresponds to a carbon dioxide content of 9 vol. % accordingly, air-line respirators and SCBA units must be used with relatively small carbon dioxide concentrations in the air. 

Air-line respirator Hose mask with blower... 

Air-purifying half-mask or mouthpiece respirator with filter pad or cartridge Air-line respirator Air-line abrasive-blasting respirator Hose mask with blower... 

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