The Public Announcement (PA) System—One-way Emergency Voice Communication System
Updated: Oct 21, 2019
You may have heard this pre-recorded message commonly throughout the building, during a fire alarm emergency activation: “Ladies and gentlemen, your attention please. A fire alarm has been activated in the building. We are investigating the cause of the alarm. Please remain calm and standby for further instructions.”
This message is being broadcast from the Emergency Voice Communication (EVC) System The EVC System has two types of systems that are linked to the Automatic Fire Alarm System, namely the Public Announcement (PA) System (One-way type) and the Fireman Intercom (Two-way type).
In this post, we shall look into the PA System that is crucial in ensuring an orderly evacuation of personnel during emergencies and assists the in-house fire wardens, Company Emergency Response Team (CERT) and relevant authorities in fire-fighting operations
Located at the Fire Command Centre (FCC), the area is only accessible for Authorized Personnel such as the Building Management, Approved Contractors and the Regulatory Authorities.
The following regulations thus require premises to have an operationally-ready and well maintained Emergency Voice Communication (EVC) System:
Code of Practice for Fire Precautions in Buildings 2018 (Fire Code 2018)
Code of Practice for Emergency Voice Communication System in Buildings (SS 546: 2009 - formerly CP 25: 1999)
Who is responsible for the EVC System - One-way?
Building Owners and Council Members are responsible by regulation
Fire Protection Specialists, like BSE, MCST Managing agencies, and/ or technicians are engaged to assist Building Owners and Council Members
Basic features of the EVC System - One-way
Control stations that can enable announcements to be made, both manually and automatically to personnel, to facilitate a quick and orderly evacuation from the building in the event of emergencies
Network of loudspeakers installed in strategic locations of the building
Overriding facility to operate by silencing all the alarm sounding devices in the building, but only after the fire alarms have operated not less than 15 seconds.
Recording system of not less than 120 minutes continuous recording duration
Fault monitoring facility, power amplifiers, batteries power source, and
Interface with the Fire Alarm System
What kind of maintenance will the EVC System - One-way need and how often?
According to regulations, the recommended frequency of inspection, testing and maintenance of the EVC System - One-way in buildings is NOT MORE THAN THREE (3) MONTHS. However, the regulatory testing and maintenance of the EVC System - One-way are conducted ANNUALLY, in conjunction with the Fire Alarm System and its related Fire Protection equipment
For industrial buildings with a higher risk of fire incidents, more frequent testing and maintenance may be conducted to ensure Total Fire Safety in the premises.
Inspection checklist for the EVC System - One-way:
On a recommended NOT MORE THAN THREE (3) MONTHS basis:
Inspect that the EVC equipment is not obstructed
Inspect the visible indications on the control station panel
Inspect the risk of fire hazards near the location of the equipment
Inspect the availability of the operating instructions
Inspect the standby battery power source
On a recommended ANNUAL basis:
Same as the above NOT MORE THAN THREE (3) MONTHS basis
The EVC System is manually tested via the simulation of a fire or fault scenario to determine the performance against the system design and regulatory requirements:
Measure the time required for the system to broadcast in an emergency mode
Test that all non-emergency functions are disabled during emergency mode
Test that the system is able to broadcast warning and speech signals in one or more areas simultaneously
Test that the system is able to receive indications of the correct functioning
Test the fault scenario between the communication link of the equipment and the fire alarm system
Test that the loudspeakers can transmit the messages based on the speech intelligibility and sound pressure level requirements
Test any auxiliary functions linked to the equipment
Next, defects are identified for recommendation and rectified in a timely manner.
Tips on having an optimum EVC System - One-way:
Ensure that the interface with the Fire Alarm System is connected and working in order, in the event of an emergency
Ensure that automated pre-recorded messages are able to be broadcast to all loudspeakers in the building
Ensure that the microphone can be used manually to broadcast to all loudspeakers in the building