Every school bus shall be equipped with at least one pressurized, dry chemical-type fire extinguisher, mounted in the manufacturer’s extinguisher bracket and located in the driver’s compartment in full view of and readily accessible to the driver. A pressure gauge shall be so mounted on the extinguisher so that it may be easily read without removing the extinguisher from its mounted position. The fire extinguisher shall have a minimum capacity of two and one-half pounds (2 ¹ / ₂ lbs.) and be of a type approved by the Underwriters Laboratories, Inc., with a rating of not less than ten (10) B:C. The operating mechanism shall be sealed with a type of seal that will not interfere with use of the fire extinguisher.