| Material |
Vapor Density |
| Ammonia |
0.59 |
| Ethelyene |
0.972 |
| AIR |
1.0 |
| Butane |
2.04 |
| Freon-12 |
4.17 |
|
The density of a gas or vapor can be compared to the density of the ambient
atmosphere. Vapor or gas that is greater in density than the ambient air tends to settle
to the lowest point. Vapor density close to the density of air or lower tends to disperse
in the atmosphere.
In settling, dense vapor (v.d. >1) creates many hazards. If the vapor displaces enough
air to reduce the atmospheric concentration of oxygen below 16%, asphyxia may result. If
the vapor is toxic, inhalation problems predominate even if the atmosphere is not oxygen
deficient. If a substance is explosive and very dense, the fire/explosive hazard may be in
the form of vapor trails which can spread far from the liquid. Flashback can occur if an
ignition source is present.
|
