Thursday, February 17, 2011

IBC Occupancy Classifications for Fire Alarm

Occupancy Classifications Based on the International Building Code

Occupancy classifications are broken down in the IBC or International Building Code.  These different groups are made up for different uses and structures.  As you guessed, each occupancy classification has its own fire alarm system requirements. These fire alarm requirements are found in the IFC or International Fire Code section 907.  Below is a simple  breakdown of what each occupancy classification is used for.  We have also included links that will take you directly to the fire alarm requirements for each group.

Occupancy Groups

Assembly Group A:  Uses intended fro the gathering together of persons for the purposes such as civic, social or religious functions, recreation, food or drink consumption or awaiting transportation.  A room of less than 50 persons used for assembly but is accessory to a different occupancy shall be considered that different occupancy.  Assembly areas less than 750 s.f. which is accessory to a different occupancy is not considered assembly.  Assembly rooms which are accessory to Group E are not considered as Group A.  Religious education rooms and auditoriums with occupant loads less than 100 persons which are accessory to churches are considered A-3.  Group A is divided into five sub groups as follows:

A-1: Usually with fixed seating, intended for production and viewing of the performing arts or motion pictures.
A-2: Uses intended for food and drink consumption.
A-3: Uses intended for worship, recreation or amusement and other assembly uses not otherwise classified.
A-4: Uses intended for viewing of indoor sporting events and activities with spectator seating.
A-5: Uses intended for participation in or viewing outdoor activities.

Click here to find out what fire alarm equipment is required for Group A Occupancy.

Business Group B:  Assembly occupancies less than 50 persons and/or uses intended for office, professional or service type transactions, including storage of records and accounts.

Click here to find out what fire alarm equipment is required for Group B Occupancy.

Educational Group E:  Uses intended by 6 or more persons at any time for educational purposes through the 12th grade.  Daycare uses for educational, supervision or personal care services for more than 5 children older than 2 1/2 years of age.

Click here to find out what fire alarm equipment is required for Group E Occupancy.

Factory Industrial Group F:  Uses intended for assembling, disassembling, fabricating, finishing, manufacturing, packaging, repair or processing operations that are not classified as Group H Hazardous or Group S Storage.  Group is divided into two sub groups.

Group F-1: Moderate Hazard
Group F-2: Low Hazard

Click here to find out what fire alarm equipment is required for Group F Occupancy.

High-Hazard Group H:  Uses intended for manufacturing, processing, generation or storage of materials that constitute a physical or health hazard in quantities in excess of those allowed by code.  Group H is divided into 5 sub groups.

Group H-1: Detonation Hazard
Group H-2: Accelerated Burning
Group H-3: Materials that readily support combustion or pose a physical hazard.
Group H-4: Materials are health hazard
Group H-5: Semiconductor fabrication facilities and comparable R&D areas which HPM's are used.

Click here to find out what fire alarm equipment is required for Group H Occupancy.

Institutional Group I:  Uses intended in which people are cared for or live in a supervised environment, having physical limitations because of health or age are harbored for medical treatment or other care or treatment or in which the liberty of the occupants is restricted.  Group I is divided into four sub groups.

Group I-1:  Houses more than 16 persons, on a 24 hour basis, who because of age, mental disability or other reasons, live in a supervised residential environment that provides personal care services.  The occupants are capable of responding to an emergency situation without physical assistance from staff.
Group I-2:  Used for medical, surgical, psychiatric, nursing or custodial care on a 24 hour basis of more than 5 persons who are not capable of self-preservation.  Less than five people shall be considered a Group R-3.
Group I-3:  Is inhabited by more than five persons who are under restraint or security and is occupied by persons who are generally incapable of self-preservation due to security measures not under the occupant's control.

Click here to find out what fire alarm equipment is required for Group I Occupancy.

Monday, February 7, 2011

Why is CI Cable Required by Code?

A lot of fire alarm salesman and installers are probably wondering why CI cable is required. 

On March 12, 1984, a fire started within a retirement home in the City of Delaware, Ohio.  Smoke detectors located withing the common area sensed the fire and activated the NACS (notification appliance circuits (NAC Voltage Drop Calculations).  However, the fire quickly engulfed the surface mounted metal raceways and damaged the internal circuits.  The damage was so severe that it disabled the notification devices from sounding.  Due to the rapid silencing of the fire alarm system, some of the residents believed the signals to be false and did not evacuate.  By the time the residents learned the a the fire was in fact real it had grown large large enough to block their exits.  Two of these residents died - one from smoke inhalation and the other had a heart attack.  On top of that 7 others where injured.

In order for the fire department to properly evacuate a building they need the fire alarm system to operate through the emergency.  At least long enough for the occupants to reach safety.  In some case total evacuation is not necessary and could cause more harm than good.  This is the reason for voice evacuation and mass notification systems.  For more information on Mass Notification and Voice Evacuation read on the Notifier Onyx Series Fire Alarm Systems.

With CI cable you can be assured that the circuits have a 2 hour window of survivability.  This in most cases will be enough time to warn the occupants and respond accordingly.

What is CI Cable?

Circuit Integrity or CI Cable

The invention of CI (circuit integrity) cable has given fire alarm technicians an easy alternative to the standard MI (mineral insulated) cable.

Previously, in order to achieve the 2 hour fire rating fire alarm installers have been forced to utilize the MI cable which is copper conductors with a magnesium oxide insulation covered by a copper sheath.  Due to the MI (mineral insulated) cable's difficult installation characteristics it is typically used for emergency power circuit feeds for fire pumps and emergency generators.  However, an alternative to MI cable is now available.

CI (circuit integrity) cable is typically soft jacked with solid conductors which is also listed for use in fire alarm and voice communication systems.  The CI cable's soft jacket changes state when it is exposed to high temperatures, creating a fire resistant insulator.  However, until the CI cable's jacket is subjected to the high temperatures of a fire the cable is as flexible as your standard cable (FPLR, FPLP, etc.).  These characteristics make it as easy to install as any other cable.  Your technicians can pull it through standard raceways and conduits as well as install it without any special tools or training.  Be aware prices are not cheap!

Find out how and why CI and MI cables where demanded.