UFC 3 -520-01
June 10, 2002
F-13.2.2 Ordinary Buildings. There are many spaces where electric lighting controls
can save energy using similar principles. These include spaces like offices and
classrooms with windows. Automatic controls of electric lighting should be used in
fenestrated spaces when a life cycle cost benefit can be demonstrated.
F-13.3
fluorescent or compact fluorescent lamps; photosensors; and other related control
devices. Dimming of HID lamps ca n be expensive and does not always work well; step-
lighting controls are preferred for HID systems. Daylighting systems require careful
installation and testing to achieve the desired results.
F-14
EMERGENCY AND EXIT LIGHTING.
F-14.1
Background .
F-14.1.1 The purpose of emergency lighting is to ensure the continuation of
illumination along the path of egress from a building and provide adequate light for the
orderly cessation of activities in the building. The purpose of exit lights is to identify the
path of egress. Both types of lighting are to be powered from both a normal power
source and an emergency source, with automatic switching from one to the other.
F-14.1.2 In some specific situations, emergency lighting might be required for specific
spaces or work areas that are not on the path of egress. There are often areas where
work of a critical nature must continue regardless of loss of normal power, such as a
computer mainframe room.
F-14.1.3 In health care facilities, including hospitals, skille d nursing homes, and
residential custodial care facilities, lighting for the path of egress (including exit signs)
and elevator cabs is considered "life safety" lighting and must be connected to the life
safety branch of the facility's emergency power system. Task illumination at
anesthetizing locations, patient care areas, laboratories, intensive care units, recovery
rooms, and other locations as required by NEC Article 517 (2002 Edition) are
considered "critical" lighting and must be powered from the cri tical power branch of the
facility's emergency power system.
F-14.1.4 Emergency lighting and exit sign requirements are related, but separate.
Note that the installation of exit signs does not automatically satisfy the emergency
lighting requirements of NFPA 101. Regardless of the exit sign design, ensure that the
emergency lighting requirements are also met. In summary, provide emergency
illumination for a period of 1.5 hours in the event of failure of normal lighting. Arrange
emergency lighting facilities to provide initial illumination that is not less than an average
of 10 lux (1 footcandle ) and a minimum at any point of 1 lux (0.1 footcandle ) measured
along the path of egress at floor level. Illumination levels are permitted to decline to 6
lux (0 .6 footcandle ) average and a minimum at any point of 0.6 lux (0.06 footcandle ) at
the end of the emergency lighting time duration. Do not exceed a maximum -to-
minimum illumination uniformity ratio of 40 to 1.
F-24
Previous Page
