§120.6(f) applies to all nonresidential new construction elevators, as well existing elevators undergoing major alterations involving mechanical equipment, lighting and/or controls. The goal behind this measure is to save energy by reducing light power density of the elevator cab lighting and requiring a minimum wattage per cfm for ventilation fans in cabs without air conditioning. Both the lighting and ventilation fans are to be controlled in such a way to shut off when the elevator has been unoccupied for an extended period of time.
10.10.2.1 Elevator Lighting Power Density
The lighting power density of an elevator cab shall not exceed 0.6 watts per square foot (W/sq ft). This is determined by taking the total wattage of the elevator lighting and dividing by the area of the elevator in square feet. Interior signal lighting and interior display lighting are not included in the total wattage of the elevator lighting.
Example 10-66
Question
An elevator with a length of 6 ft and a width of 8 ft has 9 LED lamps at 3 Watts each. Does this comply with §120.6(f)1?
Answer
Yes. 9 Lamps * 3 Watts/Lamp = 27 Watts. The square footage of the cab is 6ft*8ft = 48 ft2. The lighting power density is equal to 27 Watts/48 ft2 = 0.56 W/ft2, which is less than 0.6 W/ft2.
10.10.2.2 Elevator Ventilation CFM Fan Performance
Ventilation fans for cabs without space conditioning shall not exceed 0.33 watts per cubic feet per minute of airflow (W/cfm) at maximum speed. Elevator cabs with space conditioning are excluded from this measure.
10.10.2.3 Elevator Lighting and Fan Shutoff Control
When the elevator cab is stopped and unoccupied with doors closed for over 15 minutes, the cab interior lighting and ventilation fans shall automatically switch off until elevator cab operation resumes. This can be accomplished with an occupancy sensor, or more elaborate built in elevator controls.
There are no prescriptive measures for elevators.
10.10.4.1 An elevator installation is considered an addition when the location of the installation did not previously contain an elevator.
10.10.4.2 An alteration is a change to an existing elevator system that is not an addition or repair. An alteration could include installing new controls or a new lighting system.
•A repair is the reconstruction or renewal of any part of an existing elevator system for the purpose of its maintenance. For example, the replacement of lights or cosmetic features.
10.10.4.3 Any addition or altered space must meet all applicable mandatory requirements. Repairs must not increase the preexisting energy consumption of the repaired component, system, or equipment; otherwise, it is considered to be an alteration.