13 During a rail accident you see a tank car with a placard

13. During a rail accident, you see a tank car with a placard of UN 1888. There is a fire involving the adjacent tank car. (a) Are you worried about a fire from the tank car placarded with 1888? (b) What would be the danger of exposure to the contents of this car? (c) Would the vapor hug the ground?

Solution

a) UN 1888 sign indicates that the tank car contains chloroform. Chloroform does not catch fire (fire hazard 0 as per NFPA). Hence we should not be worried about the risk of fire.

b) Chloroform is a hazardous chemical. The following are the major hazards:

- It is designated as carcinogen and hence contact should be avoided

- Contact with chloroform may irritate and burn the skin and eyes

-Contact can irritate nose and throat

-Exposure can cause headache, dizziness and there is danger of losing consciousness all together

-Severe exposure may cause heart to beat irregularly and may cause death

-Chloroform may damage liver, kidneys and nervous system

-Chloroform may damage developing fetus.

c) The density of chloroform under normal atmospheric conditions (1.49 g/cm³) is more than density of air( 1.225 g/cm³). Since it is heavier it will try to displace air around the leakage point, i.e it will hug the ground. Hence it is advisable to use oxygen musk as well as protective clothing for any damage repair. Fire fighters should use upwind positions for spraying water.