# Fire Safety During Fit-Out Works: Hot Work, Isolations and Escape

> Fire safety during fit-out works means managing the risk while a floor is half-built: hot work near combustibles, detection and sprinklers isolated or impaired, packaging and materials stored on the floor, and escape routes narrowed by the works. It is controlled by permits to work, a written isolation procedure, daily housekeeping and temporary measures agreed before work starts.

## A floor is most exposed while it is being fitted out

Fire safety in a finished office rests on its systems: detection, alarm,
sprinklers, compartments, escape routes. The common assumption is that those
systems protect the floor during the works as well. Often they do not, at least
not fully.

During a fit-out the risk peaks. **Fuel** is at its highest: cartons, plastic
wrapping, timber offcuts, adhesives, paints and solvents on an open floor.
**Ignition sources** multiply: welding and grinding, temporary electrics,
extension leads, tools on charge. **Protection is reduced**: detector heads
covered against dust, sprinkler sections drained while heads are moved, fire
doors propped open for deliveries. And the people on the floor are workers who
may not know the building's escape routes.

For a business the consequences go beyond the damage. A fire on a fit-out site
can delay a move by months, complicate insurance claims, and in an occupied
building put staff at risk. Even false alarms carry a cost, through evacuations
of the whole building and lost goodwill with the landlord and other tenants.

## Where the risk comes from, and how it is controlled

| Risk | Typical cause during fit-out | Usual control |
| --- | --- | --- |
| Hot work | Welding, cutting, grinding, brazing, torch-applied membranes | Permit to work, area preparation, fire watch, extinguisher at hand |
| Impaired detection | Detector heads covered or zones isolated against dust | Written isolation procedure, limited zones, restoration each shift |
| Impaired sprinklers | Sections drained to move heads for the new ceiling | Short, planned isolation; rest of system live; restoration checked |
| Combustible storage and waste | Packaging, offcuts and materials stored on the floor | Daily removal, designated storage away from exits and risers |
| Flammable liquids | Paints, adhesives, solvents, thinners | Limited quantities on the floor, closed containers, ventilation |
| Temporary electrics | Overloaded boards, damaged leads, chargers left on | Proper temporary distribution, inspection, switch-off at end of day |
| Escape routes | Hoarding, stored materials, temporary partitions | Routes kept clear, signed and checked daily |

Construction safety, including fire safety on site, is addressed in
**NBC 2016, Part 7**, which deals with construction management, practices and
safety. The arrangements for a particular site are agreed by the contractor,
building management and the project's safety and fire advisers.

## Hot work permits

Hot work is any task that produces heat, sparks or flame. In an office fit-out
that typically includes welding steel supports, cutting and grinding, brazing
refrigerant pipes and torch-applied waterproofing on terraces and wet areas.
Fire precautions for welding and cutting are set out in **IS 3016**.

A working permit system usually covers:

- **The task and the place**, stated precisely, with a start and end time.
- **Preparation of the area**: combustibles removed or covered with fire-resistant
  sheets, openings in floors and walls protected so sparks cannot travel.
- **Detection in that zone**, if it must be isolated, isolated only for the
  task and restored afterwards.
- **Fire-fighting equipment** at the work point.
- **A fire watch** during the work and for a period afterwards, set by the
  site's procedure, because smouldering material can ignite later.
- **Sign-off on completion**, confirming the area was checked before the
  permit closed.

The most effective control is to need less hot work. Mechanical and press-fit
pipe joints, bolted connections, cold cutting and prefabrication away from the
floor all reduce it, and scheduling unavoidable hot work before combustible
finishes and furniture arrive reduces the fuel nearby.

## Isolating detection and sprinklers without leaving the floor unprotected

Fit-out work regularly affects the base-building fire systems. Dust and fumes
set off detectors, so heads are covered or zones are isolated. New ceilings and
layouts mean sprinkler heads must move, so sections are drained. Neither is
unusual. The danger lies in an isolation that is undocumented, wider than
needed or never reversed. How these systems work is covered under
[fire detection and alarm](/services/mep/fire-detection-and-alarm) and
[firefighting systems](/services/mep/firefighting-systems).

A sound isolation procedure answers these questions in writing:

- **Who authorises** an isolation, and who restores it.
- **Which zone or section**, as small as practicable, and for how long.
- **What covers the gap**: a fire watch, additional extinguishers, a stop on hot
  work in that area while it is unprotected.
- **How it is recorded**, in a log kept with building management.
- **When it is restored**: typically at the end of each shift, with detector
  covers removed and the zone checked.
- **Who must be told**: building management, the security desk, and anyone else
  the building's procedures or the insurance policy require.

Sprinkler heads also need protection while finishes go on; paint on a head can
affect how it operates. Heads moved to suit the new layout should be
coordinated with the ceiling design, and the system restored and checked before
the area is closed up.

## Storage, housekeeping and temporary electrics

Most site fires start small, in waste or stored materials, and grow because
nothing stopped them. Daily discipline matters more than any single measure:

- **Packaging off the floor every day.** Cartons and plastic wrap are the largest
  single fuel source on a fit-out.
- **Designated storage** for materials, away from escape routes, exits, risers
  and electrical rooms.
- **Flammable liquids** kept to the quantity needed for the day, in closed
  containers, in a ventilated area.
- **Temporary electrical distribution** with appropriate protection, inspected
  regularly, with no daisy-chained extension leads, and switched off at the end
  of the day.
- **Fire extinguishers** selected for the hazards present, positioned near work
  fronts and exits, and kept accessible. Selection, installation and maintenance
  of first-aid extinguishers are covered by **IS 2190**.
- **Fire-stopping as you go.** Openings made in walls and slabs for services
  should be sealed as the work proceeds, not left until the end.

## Escape routes in an occupied building

Where people continue to work in the building, or on the same floor, the escape
routes that protect them must keep working throughout the fit-out. Hoarding,
stored materials and temporary partitions must not block or lengthen a route
without that being agreed. Fire doors must not be wedged open for convenience.
Exit signs must remain visible, and the alarm must be audible inside the works
area. Every worker should be inducted on the evacuation route and assembly point
on their first day.

Fire and life safety provisions, including escape, sit in **NBC 2016, Part 4**.
What is acceptable during works in a particular building must be agreed with the
building's fire consultant, building management and, where relevant, the
authority having jurisdiction. The phasing, dust and services side of working
around staff is covered in
[fitting out an occupied office](/blog/fit-out-in-an-occupied-office-phasing-noise-and-dust),
and what a works policy typically covers in
[contractor's all risk insurance for fit-out](/blog/contractors-all-risk-insurance-fit-out).

## Common mistakes

- **Detector covers left on.** Put on to stop false alarms and forgotten, they
  leave an area unprotected long after the works.
- **Permits issued from the office.** A permit signed without anyone looking at
  the work area protects nobody.
- **Packaging left overnight.** The largest fuel load on the floor sits next to
  the day's ignition sources.
- **Isolating a whole floor for one room.** Convenient, and far wider than the
  risk requires.
- **Materials stored in stair lobbies or corridors.** Out of the way of the
  works, and in the way of escape.
- **No fire watch after hot work.** Smouldering material ignites after the crew
  has left.

## What to ask your contractor before work starts

- Who issues hot work permits, and who checks the area before and after?
- What is the isolation procedure for detection and sprinklers, and who signs it?
- Which zones will be isolated, for how long, and what covers the gap?
- Where will materials, flammable liquids and waste be stored?
- How are escape routes, fire doors and signage kept clear and checked?
- What fire-fighting equipment will be on the floor, and where?
- How are workers inducted on evacuation?

## Standards referenced

Construction management, practices and safety in **NBC 2016, Part 7**; fire and
life safety in **NBC 2016, Part 4**; fire precautions in welding and cutting in
**IS 3016**; selection, installation and maintenance of first-aid fire
extinguishers in **IS 2190**. The fire safety arrangements for works in a
specific building, including isolations of fire systems and the maintenance of
escape routes, must be agreed with the building's fire consultant, building
management and the authority having jurisdiction.

## Frequently asked questions

### What is a hot work permit?

A written authorisation for a specific task that produces heat, sparks or flame, such as welding, cutting, grinding, brazing or torch-applied waterproofing, at a stated place and time. It is issued only after the area has been checked and prepared, and it names the precautions, the fire watch and the person responsible. Fire precautions for welding and cutting are set out in IS 3016.

### Can the fire alarm be switched off during fit-out works?

Individual zones are sometimes isolated to stop dust or fumes from causing false alarms, but this should be done under a written procedure: authorised, limited to the affected zone, recorded, covered by temporary measures, and restored at the end of each shift. Whether and how isolation is acceptable in a particular building is agreed with building management and its fire consultant.

### What happens to the sprinklers during a fit-out?

Sprinkler heads often have to move to suit the new ceiling and layout, which may mean draining or isolating a section. That section should be isolated for as short a time as possible, the rest of the system kept live, heads protected from paint and damage, and the system restored and checked afterwards. Any isolation should be recorded and agreed with building management in advance.

### Who is responsible for fire safety on a fit-out site?

Responsibility is shared and should be written down. The contractor manages the works area, permits, housekeeping and its workforce. Building management controls the base-building fire systems and the wider escape arrangements. The client has duties to its own staff where the building is occupied. The arrangements and any approvals are agreed with the building's fire consultant and, where relevant, the authority.

### Can hot work be avoided in an office fit-out?

Often it can be reduced. Mechanical or press-fit pipe joints, cold cutting, bolted connections and prefabrication off site all reduce the amount of welding and cutting done on a live floor. Where hot work is unavoidable, scheduling it when the floor is unoccupied and before combustible finishes arrive reduces the risk.

### Do fire extinguishers on a construction site follow a standard?

Selection, installation and maintenance of portable first-aid fire extinguishers are covered by IS 2190, which relates the type of extinguisher to the class of fire. On a fit-out the types, quantities and positions should match the hazards of the works, such as electrical equipment, flammable liquids and packaging, and be kept accessible near work fronts.

## Sources

- [NBC 2016, Part 7](https://www.bis.gov.in/standards/national-building-code/) — Construction management, practices and safety
- [NBC 2016, Part 4](https://www.bis.gov.in/standards/national-building-code/) — Fire and life safety
- [IS 3016](https://standards.bis.gov.in/website/published-standards/department-wise) — Code of practice for fire precautions in welding and cutting operations
- [IS 2190](https://standards.bis.gov.in/website/published-standards/department-wise) — Selection, installation and maintenance of first-aid fire extinguishers

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Source: https://hagerstone.com/blog/fire-safety-during-fit-out-works