M1305.1.4 Appliances under floor
Underfloor spaces containing appliances requiring access shall have an unobstructed passageway large enough to remove the largest appliance, but not less than 30 inches (762 mm) high and 22 inches (559 mm) wide, nor more than 20 feet (6096 mm) long when measured along the centerline of the passageway from the opening to the appliance. A level service space at least 30 inches (762 mm) deep and 30 inches (762 mm) wide shall be present at the front or service side of the appliance. If the depth of the passageway or the service space exceeds 12 inches (305 mm) below the adjoining grade, the walls of the passageway shall be lined with concrete or masonry extending 4 inches (102 mm) above the adjoining grade in accordance with Chapter 4. The rough-framed access opening dimensions shall be a minimum of 22 inches by 30 inches (559 mm by 762 mm),where the dimensions are large enough to remove the largest appliance.
1. The passageway is not required where the level service space is present
when the access is open, and the appliance can be serviced and removed
through the required opening.
2. Where the passageway is unobstructed and not less than 6 feet high
(1929 mm) and 22 inches wide for its entire length,the passageway
shall not be limited in length.