Administrative Code Section 27-795 requires all boilers having an operating pressure in excess of 15 psi (103.4 kPa) and a rating in excess of 10 HP to be operated by a licensed high-pressure boiler operator.
Historically, boilers that were rated for 10 HP had a water-side heating surface area below 10 square feet (9.3 m²).
The horsepower rating was an indirect measure of the heating surface area.
Current boiler technology enables boilers having a heating surface area below 100 square feet (9.3m²) to be rated above 10 HP.
The intent of §27-795 was to require high-pressure boilers having heating surface areas of 100 square feet (9.3 m²) or more to be operated by licensed individuals.