Asphyxiation Hazard

When using inert gas, provide protection against personnel asphyxiation hazards... 

For filter boxes, provide remote and automatic filter box lid closing on trip of appropriate fire detection device. Fire detection device may also be interlocked to stop solvent feed, trip deluge internal to filter box and/or trip inert gas blanket for filter box (caution, be aware inert gas is a potential asphyxiation hazard)... 

Provide nitrogen backup to instrument air (caution be aware of potential asphyxiation hazards)... 

Hot gases rise by thermal lift. Henee in the open air they will disperse. Within buildings this is a serious eause of fire esealation and toxie/asphyxiation hazards if smoke and hot gases are able to spread without restrietion (or venting) to upper levels. 

Gaseous fire extinguishing systems precautions for toxic and asphyxiating hazards (withdrawn) General fire precautions aboard ships being fitted out or under repair Eire precautions m pressurized workings Access to road tankers... 

GS16 Gaseous fire extinguishing systems precautions for toxic and asphyxiating hazards. 

Furthermore, even if no ignition takes place, escaping hydrogen may accumulate into closed spaces adjacent to the source posing asphyxiation hazard for the people being there. Hydrogen dispersion may be considered safe only when no ignition occurs and no space confinement exists. 

COz is a nonflammable gas, therefore it does not present a tire or explosion hazard. The gas is generally considered toxic but will displace oxygen in the air, since it is 1.5 times heavier that air it wall settle and air supplies will be pushed out of the area. The CO2 gas is considered an asphyxiation hazard to personnel for this reason. Since the gas is odorless and colorless it cannot be easily detected by human observation in normal environments. Fire protection CO2 gas is normally stored under high pressure as a liquid and expands 350 times its liquid volume upon release. 

The normal concentration of oxygen in air is from 21 to 17 percent. When the concentration of oxygen in air drops below 18 percent, personnel should consider vacating or not entering an area due to an asphyxiation hazard. Alternatively they can be provided with protective self contained breathing apparatus to work in low oxygen environments. 

Toxicology Probably a simple asphyxiant Hazardous Decomp. Prods. Heated to decomp., emits highly toxic fumes of F and Cl ... 

It is important not only to consider the hazards associated with the low temperatures of cryogens, but to remember that each cryogen itself may have other hazardous properties specifle to that particular chemical. Liquid nitrogen and liquid helium present only asphyxiation hazards as gases while carbon... 

Equipment with large internal volumes may be filled to a slight positive pressure with dry, oil-free air or nitrogen after all openings have been sealed and valves closed. Parts in suitable plastic bags may be purged with inert gas or evacuated and sealed. The potential asphyxiation hazard needs to be considered if nitrogen is used. 

However, the lower flammable limit of only 4 percent by volume of hydrogen in air is reached before the asphyxiation hazard level is achieved. The flammable gas hazards of hydrogen far exceed the asphyxiant hazards. Safe handling of hydrogen requires close attention to its flammability hazards. 

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