Four electricians are discussing transformer installations. Electrician A says that there's no size requirement for the door sill of a transformer vault as long as the sill contains the oil from the largest transformer. Electrician B says that the AHJ can require a fire rating of three hours for vault doors on an exterior wall. Electrician C says that the minimum height requirement for the sill is 3". Electrician D says that a three-hour fire-rated door is even required for a vault with an automatic sprinkler system. Which of the following statements is correct?
A. Electrician B is correct
B. Electrician C is correct.
C. Electrician A is correct
D. Electrician D is correct