question 21
A class 1 Div 1 location is one in which____________ .
a.) ignitable concentrations of flammable gases or vapors can exist under normal operating conditions.
b.) ignitable concentrations of such gases or vapors may exist frequently becuase of repair or maintenance operations or becuase of leakage.
c.) breakdown or faulty operation of equipment or processes might release ignitible concentrations of flammable gases or vapors, and might also cause simultaneous failure of electrical equipment.
d.) all of these
my answer is D. what am i missing?
A class 1 Div 1 location is one in which____________ .
a.) ignitable concentrations of flammable gases or vapors can exist under normal operating conditions.
b.) ignitable concentrations of such gases or vapors may exist frequently becuase of repair or maintenance operations or becuase of leakage.
c.) breakdown or faulty operation of equipment or processes might release ignitible concentrations of flammable gases or vapors, and might also cause simultaneous failure of electrical equipment.
d.) all of these
my answer is D. what am i missing?