Gasoline Safety
Danger Factor #2:  Vapor Density
nDefinition: The ratio of a product’s vapor
 to the density of air.  (Air = 1)
4.9
105°F
Paint thinner
4.8
100-140°F
Safety solvent
4.5
100°F
Kerosene
4.8
95°F
Turpentine
3 to 4
-45°F
Gasoline
1.56 (at 329°F)
-156°
Propane
Vapor Density
Flash Point
Product
Danger Factor #2:  Vapor Density
       Vapor density is defined as the ratio of a product’s vapor to the density of air. Substances with a vapor density greater than 1 are heavier than air and tend to accumulate at the low level of enclosed spaces.
       Several products on our list have heavier densities than gasoline. However, when their risk of vapor ignition is taken into account, they are not as dangerous, mainly because their flash points are much higher. Similarly, while propane has a lower flash point than the other products, its vapor is almost as light as air.
(Bridge)  Finally, we’ll look at flammable range as a risk factor.