Why So Risky inChemical Factories

Which is safer一staying at home,traveling to work onpublic transport,or working in the office?Surprisingly,each of these carriesthe same risk,which is very low.

However,what aboutflying compared to working in the chemical industry?Unfortunately,the former is65 times riskier than the latter!In fact,the accident rate of workers in

the chemicalindustry is less than that of almost any of human activity,and almost as safeas staying at home.

The trouble with thechemical industry is that when things go wrong they often cause death to thoseliving nearby.It is this which makes chemical accidents so

newsworthy.Fortunately,theyare extremely rare.The most famous ones happened at Texas City(1947),Flixborough(1974),Seveso (1976),Pemex(1984)and Bhopal(1984).

Some of these arealways in the minds of the people even though the loss of life was small.No onedied at Seveso,and only 28 workers at Flixborough.The worst accident of

all was Bhopal,where up to 3,000 were killed.The Texas City explosion of fertilizer killed 552.The Pemex fire at a storageplant for natural gas in the suburbs of Mexico City

took 542 lives,justa month before the unfortunate event at Bhopal.

Some experts havediscussed these accidents and used each accident to illustrate a particulardanger. Thus the Texas Cityexplosion was caused by tons of ammonium nitrate

（硝酸铵）,which issafe unless stored in great quantity.The Flixborough fireball was the fault ofmanagement,which took risks to keep production going during essential

repairs.The Sevesoaccident shows what happens if the local authorities lack knowledge of thedanger on their doorstep.When the poisonous gas drifted over the town,local

leaders wereincapable of taking effective action.The Pemex fire was made worse by anoverloaded site in an overcrowded suburb.The fire set off a chain reaction of

exploding storagetanks.Yet,by a miracle,the two largest tanks did not explode.Had these caughtfire,then 3,000 strong rescue team and fire fighters would all have died.From the passage weknow that ammonium nitrate is a kind of________.

A.natural gas,whichcan easily catch fire

B.fertilizer,whichcan't be stored in a great quantity

C.poisonoussubstance,which can't be used in overcrowded areas

D.fuel,which isstored in large tanks