Section 79. The certificate of inspection issued by the department shall state the name of the owner and that of the user, if different from the owner, the location of the boiler, the number of the boiler, the date of inspection, the maximum pressure at which the boiler may be operated and the signature of the inspector who made the inspection. The certificate shall also contain such extracts from the General Laws as shall be deemed necessary by the board. It shall be so placed in the boiler room and protected from being soiled as to be easily read.