NFPA fire alarm sound level

NFPA 72

National Fire Alarm Code
(An equipment “installation” standard)
Summary for PVAG Advisory Committee
Current Edition: 2007
Past Edition: 2002
Next Edition: 2010
Scope: Application, installation, location, performance, inspection, testing and maintenance requirements for fire alarm systems and emergency warning equipment.
(The need for a fire alarm system and the required system attributes are not specified by NFPA 72. These are from higher level codes such as NFPA 101, Life Safety Code, or from “local” statutes.)
Content Overview:

• Fundamental requirements (power supplies, supervision of wiring, signal type distinction, general performance, documentation and approval requirements)

• Requirements for detection devices (heat detection, smoke detection, manual initiation, supervisory initiation – coverage, location and spacing)

• Requirements for systems (control unit interconnection, interface with other systems, suppression system actuation)

• Requirements for notification appliances (audible, visible, tactile – see “occupant notification overview” below)

• Requirements for offsite monitoring (supervising stations, public fire alarm reporting systems)

• Requirements for inspection, testing and maintenance

• Requirements for residential smoke alarms and household fire alarm systems

Occupant Notification Overview:

• General requirements for notification appliances (listing, physical construction, mechanical protection, mounting, connection)

• Audible signaling – general requirements (high ambient noise area, maximum total sound pressure 110 dBA, intelligibility for voice systems, minimum sound level for alert and evacuation tones)

• Public mode audibility requirements (public mode includes signaling to general occupants for them to take action on their own to evacuate or relocate etc.)
  

  • 15 dB above average ambient sound levels or 5 dB above maximum ambient sound level (which ever is greater)

  • Allowances for reduction of audibility under certain conditions

• Private mode audibility requirements (private mode includes signaling to facility staff or emergency personnel to take action)
  

  • 10 dB above average ambient sound levels or 5 dB above maximum ambient sound level (which ever is greater)

  • Allowances for reduction of audibility under certain conditions

• Sleeping area audibility requirementsLocation (mounting height) requirements for audible appliances
  

  • 15 dB above average ambient sound levels, or 5 dB above maximum ambient sound level or 75dBA (which ever is greater)

• Visible signaling requirements – general requirements (light color, flash rate, flash duration, listing to UL 1971)

• Location (mounting height) requirements for visible appliances

• Spacing for visible appliances in rooms (indirect signaling – a minimum intensity of reflected light)

• Spacing for visible appliances in corridors (direct signaling – occupants view strobes directly)

• Synchronization for visible appliances (more than two appliances in same room or field of view must be synchronized to reduce potential risk of seizure to people with photosensitive epilepsy)

• Requirements for emergency voice / alarm communication systems (performance and operation)