Emergency PA Systems: IS 1220 Part 3 vs Police Spec 160

Ask an integrator in Israel which standard governs a building's public address system and you will often get two different answers, both correct. Emergency PA sits at the intersection of two regulatory regimes: Israeli Standard 1220 Part 3, which comes from the fire safety world, and Specification 160 issued by the Israel Police. They are written by different authorities, for different emergencies, and they gate different approvals. A project that satisfies only one will fail the other.

This is not a technicality that surfaces at handover. It shapes the amplifier count, the speaker layout, the location of the operator stations, and the cabling. Those are decisions that become expensive to revisit once the ceilings are closed. Understanding both requirements at the design stage is what separates a system that gets signed off from one that gets rebuilt.

What IS 1220 Part 3 governs

Israeli Standard 1220 Part 3 covers the installation of fire detection systems and their associated alerting systems. Public address is not a standalone chapter within it, which is why you will occasionally hear that "there is no PA section in 1220". Voice evacuation equipment is nonetheless certified and sold in Israel explicitly as compliant with Part 3, because the standard governs the alerting function the detection panel drives.

The defining characteristic of a Part 3 system is that it is automatic. When the detection panel confirms an alarm, the PA system broadcasts the evacuation message without a human in the loop. The message content, the zones it reaches, and the sequence in which it reaches them are all part of the fire strategy for the building, not an operator decision made under pressure.

Triggered automatically by the fire detection panel on a confirmed alarm
Zoning follows the building's fire compartmentation and evacuation strategy
Supervised speaker lines, amplifiers and batteries, with faults annunciated
A firefighters' microphone panel at the main entrance for arriving crews
Pre-recorded evacuation and alert messages, including phased evacuation where the strategy calls for it

What Police Specification 160 governs

Specification 160, with its companion 161, comes from the Israel Police rather than the standards institution or the fire service. Its purpose is different. It exists so that security forces, meaning police and in practice site security, can address everyone in a building during a security incident. That is a manual system by design. A human picks up a microphone and speaks.

The approval it gates is different too. Where Part 3 compliance feeds the fire safety approval, Specification 160 is a business licensing requirement. For a great many commercial and public buildings in Israel, the doors do not open to the public without it.

Operated manually by security forces from a designated operator station
Coverage of the entire building, explicitly including car parks and lifts
Battery backup of at least 30 minutes of operation without mains power
Amplifier capacity, speaker count and microphone placement sized to the building and its occupancy
Supervised speaker lines and an indication panel showing system status in real time
Annual inspection and maintenance, counted from the installation date

Where the two diverge

The most consequential difference is the trigger. A Part 3 system is designed around an automatic response to a detected fire; a 160 system is designed around a person deciding what to say and to whom. A single system can do both, but only if it is specified that way from the outset. The operator station, the microphone priority scheme, and the zone logic all have to accommodate two very different modes of use.

The second difference is coverage. Fire zoning follows compartmentation, and a fire strategy may deliberately leave certain areas out of the initial evacuation broadcast. Specification 160 asks for the whole building, and names car parks and lifts specifically. Those are exactly the spaces that a purely fire-driven design will sometimes treat as out of scope. Retrofitting speakers into a completed car park is not a small change order.

Third is who inspects, and how often. Part 3 is the installation standard; ongoing maintenance falls under IS 1220 Part 11, with its own inspection regime. Specification 160 carries its own annual inspection obligation running from the installation date. In practice a site with both is subject to two maintenance schedules, and the documentation for each has to hold up independently.

Intelligibility is the requirement everyone underestimates

A message that is loud but unintelligible is worse than no message, because it consumes the seconds in which people should be moving. Both regimes care about being understood, and the technical substance behind that comes from the European EN 54 family that Israeli practice leans on: EN 54-16 for voice alarm control and indicating equipment, and EN 54-24 for the loudspeakers themselves.

The benchmark to design against is a Speech Transmission Index of at least 0.5, equivalently a Common Intelligibility Scale value of 0.65 or better, measured in the occupied space rather than on a datasheet. Hitting it is an acoustic problem, not an electrical one. Reverberant spaces such as atria, stairwells, sports halls and underground car parks routinely fail intelligibility while comfortably passing a sound pressure measurement, because the reflections smear the consonants.

The practical implication is that speaker count and placement are driven by intelligibility, not by wattage. More, quieter speakers closer to the listeners will nearly always outperform fewer, louder ones in a difficult room. That is a design decision with a direct cost consequence, and it is the one most often value-engineered out before anyone measures the result.

What to verify before licensing

Long speaker circuits deserve particular attention. A 100 V line that measures correctly at the amplifier can arrive at the last speaker with meaningfully less level, and the losses are easy to miss on paper.

For checking voltage drop across long speaker and control runs, use our free Cable Voltage Drop Calculator

Confirm which approvals the building actually needs, whether fire, business licensing or both, before fixing the design
Verify the zone plan against both the fire evacuation strategy and the security concept of operations
Check that car parks, lifts and stairwells are covered if Specification 160 applies
Measure intelligibility in the finished space, in the acoustically difficult rooms, not only at commissioning-friendly locations
Confirm battery autonomy under real alarm load, not standby load
Establish both maintenance schedules and their documentation from day one

One caution on numbers. The precise tables, covering sound pressure levels by space type, cable fire ratings and permitted battery chemistries, live in the purchased standards and in the fire service directives, and they are revised. Nothing in this article substitutes for the current text of IS 1220, Specification 160/161, and the applicable directives, or for confirmation from the authority having jurisdiction over your specific building. Where a supplier tells you a product is "1220 approved", ask which part, which edition, and for the certificate.

Designed together from the start, one well-specified system satisfies both regimes without duplication. Designed separately, or retrofitted after the fact, the same building ends up with two partial systems, two sets of findings, and a licensing delay that costs more than the engineering would have.