Quick answers
What is the difference between active and passive fire protection?
Active fire protection detects, warns, controls or suppresses a fire through alarms, sprinklers, hydrants and suppression systems. Passive protection such as fire doors, firewalls, dampers and fire-rated construction is built in to slow the spread of smoke and flame. A building needs both.
Do all sprinklers turn on together when there is a fire?
No. Sprinklers normally operate individually when heat at a head reaches its activation threshold, and smoke alone does not open every head. Assuming every sprinkler activates at once is a common mistake.
How to choose the right fire protection system for a building?
Start from the occupancy and hazard, not a preferred product. Take into account local construction rules, insurance needs and the specific risks of the site, and get advice from a knowledgeable expert. Buying extinguishers or detectors without an occupancy-specific fire strategy is a mistake.
What to do if the fire alarm sounds in a building with sprinklers?
Raise the alarm and call 112, as an automatic system may not have notified responders. Evacuate by the nearest safe marked route, do not wait beneath a sprinkler, and re-enter only after emergency personnel declare the building safe.
Walk into any mall, hospital or office tower in an Indian city and you will see red pipes, small glass bulbs in the ceiling, smoke detectors, heavy doors marked “Fire Exit” and a hydrant box near the stairs. Together these make up the building’s fire protection. If you are a society committee member, a shop owner or a facility manager, it helps to know what each part does and why one part cannot do the job of another.
Two kinds of fire protection
Fire protection works in two ways, and a safe building needs both.
- Active fire protection does something when a fire starts. It finds the fire, warns people, or sprays water, gas or foam on it. Alarms, sprinklers, hydrants and special suppression systems are all active.
- Passive fire protection is built into the structure and just sits there, holding the fire back. Fire-rated walls and floors, fire doors, sealed shafts, fire dampers in ducts and the sealing around cables and pipes are all passive.
Active systems buy time and may control the fire. Passive protection keeps smoke and flame in one area long enough for people to get out and for the fire brigade to get in.
The main active systems
Fire detection and alarm
Detectors sense smoke, heat or flame and send a signal to the fire alarm panel. The panel sounds the alarm so people can leave. Anyone can also raise the alarm by pressing a manual call point. In many buildings the panel also switches off the AC, brings lifts to the ground floor, releases fire doors and starts smoke extraction.
Sprinklers
A common misunderstanding is that a smoke detector turns the sprinklers on, and then every sprinkler in the building sprays at once. In an ordinary wet-pipe system that is not how it works. Each sprinkler head has a small glass bulb or a fusible link. When the heat right at that head gets high enough, that one head opens and sprays water on the fire below it. Smoke alone does not open it. Most fires are controlled by just one or two heads. Only special systems, such as pre-action or deluge systems used for particular hazards, are released by a detection system.
Because a sprinkler starts working the moment the heat reaches it, it acts long before the fire brigade can arrive.
Hydrants and hose reels
Internal hydrants, wet risers and hose reels give trained staff and the fire brigade a ready water supply on every floor. They depend on a fire water tank and fire pumps that must be in working order every day.
Special suppression systems
Water is not the right answer for every fire. Server rooms, electrical panels, kitchens and chemical stores may need gas, foam, wet chemical or other engineered systems designed for that hazard.
Why it is worth it
- It gives people time to get out safely.
- It keeps a small fire from becoming a building fire.
- It limits damage to stock, records and machines, so you can open again sooner.
- It helps you meet the National Building Code of India 2016 and your state fire rules.
US data shows what working sprinklers can do. In the NFPA study of reported US fires from 2017 to 2021, sprinklers operated in 92% of fires that were large enough to set them off, and they controlled the fire in 97% of the cases where they operated. In 77% of fires where sprinklers operated, just one head opened. The most common reason they failed was that the system had been shut off before the fire. NFPA’s newer edition, published in October 2026 and covering 2020 to 2024, gives much the same picture: sprinklers operated in 90% of such fires, controlled the fire in 97% of cases where they operated, and just one head opened in 76%. Shut-off systems were again the most common reason for failure. These are American figures, not Indian ones, but the lesson travels: a closed valve protects nobody.
Choosing the right system
Do not start with a product. Start with the building: what it is used for, how many people are inside, how they would get out and what can catch fire. The National Building Code of India 2016, Part 4, sets the minimum fire and life-safety requirements by type of occupancy, and your state fire service may add its own. Insurance needs and the specific risks of the site also matter.
Get the design done by a competent fire engineer and the installation by a qualified agency. Then keep the as-built drawings and service records safe. You will need them for the fire NOC renewal, and the fire brigade may need them on the day of a fire.
Keeping it working
Equipment that is installed but not maintained gives false comfort. A few things to watch:
- Never close a sprinkler valve, switch off the alarm or isolate the fire pump without a written impairment procedure and someone in charge.
- Do not paint sprinkler heads, hang things from sprinkler pipes or stack goods right up to the ceiling.
- After any renovation, check that new cables, pipes and ducts passing through walls and floors are sealed again with fire-stopping.
- Keep fire doors shut and unwedged.
- Test the whole chain, not just single devices: when a detector goes off, does the alarm sound, does the AC trip, do the lifts come down?
This week, take ten minutes to walk your building. Find the alarm call point, the two exits and the assembly point. Check that no fire door is wedged open and no carton is blocking a hydrant box. If something is wrong, tell the facility manager or the society secretary the same day.
What needs attention
- Active and passive protection do different jobs, and neither can replace the other
- Detection and alarm give people time to act, but they do not always control the fire
- In an ordinary sprinkler system each head opens on its own when the heat at that head is high enough; smoke alone does not open every head
- Water is not the right agent for every hazard, so special risks need engineered suppression
- Everyday maintenance work can damage fire doors, wall openings and hidden fire barriers
- When a system is out of service, the risk must be managed at once, people told and other protection put in place where needed
Controls that reduce risk
- Ask for the approved fire plan and the current as-built drawings
- Keep a register of all alarms, detectors, suppression systems, pumps, tanks, hydrants, doors, dampers, emergency lights and smoke control
- Make sure testing checks the whole chain of cause and effect, not just single devices
- Lock or monitor key valves in their normal position and look into every unexpected shut-off
- Keep the space below sprinklers, and all hydrants, fire brigade inlets and exits, clear
- Use a written permit and a sign-off check for any work that affects fire barriers or systems
- Train occupants to respond to the alarm, and train named staff on the equipment they are responsible for
- Follow every defect until it is fixed and checked, and put temporary measures in place while a system is down
Common unsafe practices
- Buying extinguishers or detectors without a fire plan for how the building is actually used
- Believing that all sprinklers go off together, or that smoke sets them off
- Closing sprinkler valves, switching off alarms or isolating pumps without a proper impairment procedure
- Painting, blocking, damaging or hanging things from sprinkler heads and pipes
- Leaving wall openings, dampers or fire doors unprotected after renovation
- Choosing an extinguishing agent without thinking about people, electrical equipment, fuel and the effects of discharge
- Not linking the alarm with evacuation, smoke control, lifts, doors and emergency response
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