In general, refueling a bus should be done:

Question

A bus should not be refueled while passengers are on board unless it is absolutely necessary. In particular, a bus with passengers on board should never be refueled inside an enclosed building.

Accepted Answer

With passengers on board, but only if it is unavoidable.

Answer

With passengers on board.

Answer

With passengers on board if they say it is okay.

Answer

By a passenger.