# Fire Detection & Alarm Systems

> A fire detection and alarm system links smoke and heat detectors, manual call points and sounders to a conventional or addressable panel that also triggers HVAC shutdown, lift homing and public address. Its effectiveness rests on coverage and on the right detector type for each space, since a system that false-alarms gets ignored.

## What we deliver

**Fire alarm panels, smoke and heat detection, manual call points, sounders and
hooters, and interfaces** to firefighting, HVAC shutdown, lifts and public
address — installed, programmed and tested.

Detection is the part of fire safety that buys time. Suppression limits the fire;
detection is what gets people out before it matters. That makes coverage and
reliability the whole job — and a system that false-alarms constantly fails at
it too, because people stop responding.

## Scope of works

| Stage | What we deliver |
| --- | --- |
| Design | Detector type and spacing per area, zoning, panel sizing |
| Panel | Conventional or addressable control panel, repeaters |
| Field devices | Smoke and heat detectors, MCPs, sounders, strobes |
| Interfaces | HVAC shutdown, lift homing, sprinkler flow switches, PA |
| Cabling | Fire-survival cabling where required, containment |
| Programming | Cause-and-effect matrix, device addressing |
| Testing | Device-by-device test, interface test, commissioning |

## Where projects go wrong

- **Wrong detector type for the space.** The leading cause of nuisance alarms.
- **Coverage not reassessed after partitioning.** New rooms, and walls to slab,
  leave gaps.
- **Cause-and-effect never tested end to end.** The panel alarms, but the AHU
  does not shut down and the lifts do not home.
- **Detectors in the ceiling void forgotten.** Deep plenums with services can
  require detection above the ceiling as well as below.
- **No maintenance regime.** Detectors need periodic testing and cleaning to
  stay reliable.

## Why Hagerstone

**Detection, suppression and the building services it must interface with — all
in one scope**, so the HVAC shutdown and lift homing actually get tested against
the alarm rather than left as an interface between contractors.

**35-member firefighting team and 15 electricians in-house**, under ISO 9001 /
14001 / 45001 and 79+ quality checkpoints.

## Standards referenced

Detection and alarm system selection, installation and maintenance to
**IS 2189**. Fire and life safety requirements under **NBC 2016, Part 4**.

## Frequently asked questions

### Conventional or addressable fire alarm?

Conventional systems report a fire by zone — you know which area, not which device. Addressable systems identify the exact detector, which cuts the time to locate a fire or a fault dramatically in a large building. For anything beyond a small single floor, addressable is the sensible choice, and the price gap has narrowed a great deal.

### Smoke or heat detectors — where does each go?

Smoke detectors in most occupied areas, because they respond earliest. Heat detectors where smoke detectors would false-alarm — kitchens, pantries, some plant rooms, dusty areas. Choosing the wrong type is the main cause of nuisance alarms, and a system that false-alarms often trains occupants to ignore it.

### Does detection need to change when an office is re-partitioned?

Usually yes. New enclosed rooms need their own detection, and walls that run to the slab can cut off a detector's coverage entirely. Detection coverage should be reassessed against the fit-out layout, in the same exercise as sprinkler coverage.

## Sources

- [IS 2189](https://standards.bis.gov.in/website/published-standards/department-wise) — Selection, installation and maintenance of automatic fire detection and alarm system
- [NBC 2016, Part 4](https://www.bis.gov.in/standards/national-building-code/?lang=en) — Fire and life safety

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Source: https://hagerstone.com/services/mep/fire-detection-and-alarm