Building Design and False Alarms
Building design is frequently found to be the cause of unwanted false alarm activations. This usually occurs when a fire alarm system is installed in the building with little or no consideration for the activities of the occupants. It is better to address potential fire alarm problems before the building is completed and commissioned.
Suggested building design strategies for reducing false alarms:
- At the design stage, research what type of system suits your needs. Some options for smoke detectors include aspirated, laser point, beam, filtered point, video and photo optical. The latter option may be attractive as it is often less expensive to install, however in the long term choosing a system that suits your workplace and does not generate false alarms may be the most cost effective.
- At the design stage, discuss tailoring the system design to the occupants needs instead of accepting a maximum coverage design (often chosen due to its ease of complying with all Standards).
- Consider conducting a risk assessment of potential false alarm problems with your fire maintenance company prior to occupancy
- For renovations of existing buildings, consult with the designer or building contractor and make changes to the existing fire alarm system if necessary.
- Check to see if the floor plan layout has changed since the fire alarm system was originally installed.
- Consider upgrading your fire alarm system, including alarm panels to optimum standards.
- Upgrade buildings where poor internal and external plumbing design allows water penetration.
- Upgrade building design and layout where there is inadequate airflow management.
- Ensure that all appropriate signage is in place before the building is commissioned, e.g. Height restriction signs for car-parks, no smoking signs and false alarm prevention notices.
Types of Alarm Systems:
Monitored Automatic Alarms
Monitored Automatic Alarms transmit an uninterrupted signal via the Alarm Signalling Equipment (ASE), through monitoring company to a despatch centre to request attendance by the fire services.
While there are many ways these systems can be configured, there are key components to how a typical system works. Their prime objective is life safety and early notification to the fire brigade, however monitored automatic alarms also enable fire services to protect property and the environment.
Most are installed in order to comply with legislation, and there are strict procedures to follow if any changes to your alarm connection are to be made, such as modifications, isolations or disconnections.
Monitored automatic alarms can, from time to time, generate false alarm calls to the fire services. There are many ways to prevent unwanted false alarms and CFA encourages every building manager and owner to be proactive in reducing these unwanted alarms. See Monitored Automatic Alarms
Local domestic alarms (smoke alarms)
Two types of smoke alarm are available. These are either hard wired into the building (requirement for any new home built after 1 August 1997) or battery operated that can be purchased separately and installed by the owner or occupier in homes built prior to 1 August 1997. Their auditory signal is heard within the dwelling only.
Local fire alarm systems
These systems can be complex with a combination of smoke, thermal and sprinkler systems wired into a fire indicator panel. They have a local, with the building, auditory warning gong or alarm and comply with AS1670.
Security monitored alarms
These are domestic alarms or fire alarm systems that are monitored by security companies. In all cases a signal is sent back to the monitoring company, but any further action depends on the procedures agreed between the client and the security company. The fire services may not be automatically called.
Residential and domestic sprinkler systems
These are local sprinkler systems installed in residential homes or smaller buildings.
How a typical system works
A building with a direct automatic alarm has detectors that activate under certain conditions.
They are designed to detect fire situations or other hazards, however they will activate under other similar situations. For example, a smoke detector will activate if dust or steam is present causing a false alarm.
Small groups of detectors are wired into the Fire Indicator Panel (FIP) as separate circuits or zones. More complex systems may have other panels or sprinklers wired into the FIP. Each main component is then wired into the Alarm Signalling Equipment (ASE) as a separate input.
The system should be continuously monitored, and the signal automatically transmitted to dispatch the Fire brigade. Signals from and Alarm Signalling Equipment (ASE) on site are sent through to a monitoring company, which then passes the message on to the dispatch centre for action. The whole process must take less than 20 seconds to be compliant.
At the time of activation, the ASE will send a signal via the monitorig provider to the Emergency Services Telecommunications Authority (ESTA) as the dispatch centre, and fire appliances will be sent to the site according to pre-arranged turnout requirements.
Understanding your fire alarm system is essential for correct management of your building site. All sites with monitored automatic alarms should be managed by personnel who understand how the system works, and who have the knowledge to isolate individual circuits. Your fire maintenance contractor may be able to assist you with additional information about your system.
Direct Automatic Alarm: An installation connected to a fire alarm monitoring system connected to a fire station or despatch centre.
Fire Alarm System: Equipment designed to detect fire and other emergency conditions, transmit a signal and give an audible warning.
ASE – Alarm Signalling Equipment: Equipment designed to communicate alarm and fault signals together with other information between a fire alarm system and a monitoring service.
Currently there are two types of ASE in use:
- ‘Code Red’ – favoured by Chubb Fire Safety (formerly FFE)
- ‘Centaur’ – favoured by ADT
- 'Romteck' - favoured by Romteck Grid
Input: A connection into an ASE consisting of a major component of a fire alarm system eg. fire indicator panel (FIP), valve monitored alarm (VMA), sprinkler (SPR).
Zone: Specific area of a fire alarm system
Circuit: Specific line of components within a fire alarm system
Approved Monitoring Provider: A service which receives fire alarm signals and transfers those signals to a fire brigade via an automatic data link and despatch centre.
Self Evaluation Checksheet
Maintenance of Fire Alarm Systems
Modern day fire alarm systems are complex in design, and need to be maintained by a reputable fire maintenance company that has expertise in this field.
As a minimum requirement, an automatic fire alarm system should be designed, installed and maintained in accordance with the requirements of the relevant Australian Standards.
In certain environments additional maintenance is often necessary to prevent unwanted false alarms.
Does your alarm system suit your needs? Check whether any of the following apply to you:
- Have any renovations changed the building layout?
- Are the rooms being used for a different purpose?
- Has your old fire alarm system has been upgraded?
- Has a new building been constructed and standard fire protection installed without tailoring the type and calibration of detectors to the use of individual rooms or areas?
- Does your false alarm system generate faults that cannot be explained?
Be proactive - don’t wait for a false alarm to occur before you assess your site.