U.S. Census Bureau, Bowie, MD
require multiple occupancy sensors to adequately control
In addition, integrated photo/occupancy sensors shall be
a single space. Each occupancy sensor shall be marked by
provided for the following space and occupancy types:
a label identifying the panel and circuit number.
Perimeter offices smaller than 10 m2 (108 sq. ft.).
No occupancy controls shall be used in mechanical or
Photo control system shall reduce the electric lighting by
electrical rooms or other spaces where occupants could be
simple on/off, stepped dimming, or full dimming
in physical danger due to loss of light (see discussion in
controls. Control strategy can be either open-loop or
Specific Lighting Constraints).
closed loop, but needs to be programmed to minimize
lamp cycling and occupant distraction.
Photo Controls. Photosensors are typically used to either
control dimming ballasts for lumen maintenance or
Override Controls. An easily accessible local means of
reduce lighting levels in response to available daylighting.
temporary override must be provided in all spaces to
Photo sensors shall be provided for the following space
continue operations per IBC or local energy code. This
and occupancy types:
override is typically embedded in a space located timer
All regularly occupied perimeter spaces.
switch, but PC-based and other override strategies are
All other spaces that are anticipated to provide daylight
acceptable. However, overrides must be automatic; phone
that will displace the installed lighting by at least 1,000
systems that depend on facility managers to control the
full load hours per year.
local lighting are not allowed.
Interior Lighting, Daylighting, and Control Systems
Revised March 2005 PBS-P100