An owner, manager, or operator of a vehicle or equipment regulated by this chapter within twenty-four hours shall make a report to the board through the office of the State Fire Marshal of any fire or explosion in connection with the equipment or gas system which the person has serviced, installed, or performed other work upon of accidental or incendiary origin of which the person has knowledge, with as complete detail as possible, together with evidence as he has obtained after investigation of the discovery of the fire or explosion. Reports filed pursuant to this section are confidential and for the use of the board only pending investigation completion.