Pennsylvania Code › Title 34 - LABOR AND INDUSTRY › Part I - Department of Labor and Industry › Chapter 50 - GENERAL REQUIREMENTS-BUILDINGS › MANUAL AND AUTOMATIC FIRE ALARM SYSTEMS › Section 50.52 - Automatic system

Current through Register Vol. 54, No. 28, July 13, 2024
(a) An automatic
				  fire alarm system is a system designed to detect products of combustion and
				  provide automatic notification to all building occupants. It shall be composed
				  of detection devices, alarms, power source, wiring, and other related
				  components as necessary. All detection devices shall be listed as meeting U.L.
				  268, 1981 Edition.
(b) Automatic
				  detectors shall be installed to comply with the requirements of the applicable
				  occupancy division.
(c) Automatic
				  detectors shall be securely mounted on outlet boxes. Detectors shall not be
				  recessed into the mounting surface unless they have been tested and listed for
				  recessed mounting. Detectors may be ceiling or side wall mounted with a minimum
				  of 4 inches clearance from a ceiling to wall jointure measured from the
				  jointure to the top of the detector. Side wall mountings shall not exceed 12
				  inches measured from the ceiling and side wall jointure to the top of the
				  detector.
(d) Automatic detectors
				  shall be installed within the spacings or coverage used in the testing and
				  listing of the detectors by any of the accepted independent testing agencies.
				  The following considerations shall be made when determining spacing:
(1)
Smooth ceilings.
Normal
				  spacings up to heights of 12 feet or less shall be used. Reduced spacing for
				  areas over 12 feet in height shall be used.
(2)
Sloped ceilings.
Detectors within 3 feet of the peak, measured horizontally, with additional
				  required detectors at normal spacings based on horizontal measurements shall be
				  used.
(3)
Beamed ceilings.
Beams over 8 inches in depth shall reduce normal detector spacings.
				  Beams over 18 inches in depth and on 8 feet or more centers shall have each bay
				  treated as a separate area requiring a minimum of one automatic
				  detector.
(4)
Partitions.
Partitions that extend to within 18 inches of the ceiling will not
				  influence detector spacing. Partitions less than 18 inches from the ceiling may
				  affect detection capabilities requiring reduced detector spacing.
(5)
Corridors.
When spacing
				  detectors in corridors, the distance from the end wall of the corridor to the
				  first detector shall not exceed 1/2 of the maximum distance allowed between
				  first and second detectors in the corridor. The maximum distance allowed
				  between the first and second detectors in a corridor shall be based on the
				  spacing used when the detector was tested for listing by the accepted
				  independent testing agency.
(6)
Detector spacing for electromagnetic hold open devices.
When
				  doors are held open by electromagnetic devices, automatic detectors shall be
				  installed at each location. A minimum of one automatic detector is required
				  when the distance from the top of the door to the ceiling is 24 inches or less.
				  Automatic detectors are required on both sides of the door when the distance
				  from the top of the door to the ceiling is over 24 inches. The mounting
				  distance of the automatic detector from the door shall not be less than the
				  distance measured from the top of the door to the ceiling with a minimum
				  distance of 12 inches and a maximum distance of 5 feet. The detectors may be
				  side wall or ceiling mounted with a preference for ceiling mounting. Approved
				  automatic closing devices with built-in hold open mechanism and detector may be
				  used in lieu of wall or ceiling mounted devices.
(7)
Special areas.
The
				  Department may approve alternative spacing of automatic detectors in special
				  areas for specific hazards.