Autoignition, flammability terms

Butylenes are not toxic. The effect of long-term exposure is not known, hence, they should be handled with care. Reference 96 Hsts air and water pollution factors and biological effects. They are volatile and asphyxiants. Care should be taken to avoid spills because they are extremely flammable. Physical handling requires adequate ventilation to prevent high concentrations of butylenes in the air. Explosive limits in air are 1.6 to 9.7% of butylenes. Their flash points range from —80 to —73° C. Their autoignition is around 324 to 465°C (Table 2). Water and carbon dioxide extinguishers can be used in case of fire. 

No single parameter defines flammability. Commonly used terms are flash point, flammability limits, autoignition temperature, minimum ignition energy and burning velocity. 

The flammable properties of substances in air include their flash point, vapor pressure, autoignition temperatures, and flammability range (i.e., their lower and upper explosive limits). Liquids that have a flash point of <100°F (37.8°C) are termed flammable, whereas liquids that have a flash point of 100-200°F (37.8-93.3°C) are termed combustible. These terms are explained in detail... 

Highly flammable, fl. p. 17° autoignition temp., 463°, mod. toxic by inhalation. OES long-term 100 ppm short-term 150 ppm (Sk). Vapour is a skin, eye and mucous membrane irritant, and at high cone, is narcotic. Liquid defats the skin and causes erythema. ZE2450000. Picrate [38429-30-0]. 

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