Thermal Cameras for Early Fire Detection in a Factory: What Works, What India's Code Accepts, ₹
Can a thermal camera be your factory's fire detector in India? Not on its own. As of 15 Oct 2026, IS 2189:2026 lists video fire detectors (IS/ISO 7240-29) as an alarm component, but no thermal hotspot camera. NBC 2016 Part 4 does not mention video detection at all. A radiometric thermal camera is an early-warning layer on top of the certified system.
Last checked: 15 Oct 2026. The godown layout is an assumption.
Verified against
- BIS, IS 2189 : 2026, Selection, Installation and Maintenance of Automatic Fire Detection and Alarm System — Code of Practice (Fifth Revision), March 2026: foreword, clause 4.1, Table 1, clauses 5.1.4.1–5.1.4.3, inspection table. Copy hosted by the National Safety Council of India.
- BIS, National Building Code of India 2016, Part 4 Fire and Life Safety: clauses 2.4, 3.4.12(b), 4.9(g), Table 7 Note 17, reference lists 4(15) and 4(16).
- Axis datasheets: AXIS Q1961-TE, AXIS Q1951-E.
- Axis, Thermometric cameras white paper, T10171624, October 2026 edition.
- CNPP Cert. (France), certificates 32.20.221 and 33.20.221, Hikvision thermal camera heat detection systems, copy hosted by the trade title Face au Risque.
- Mama's camera-model dataset (STQC ER and BIS CRS registrations), 2,229 primary rows.
- Checked 15 Oct 2026.
Thermal, video analytics or a certified detector: by application
| Application | Radiometric thermal camera | Flame/smoke analytics on normal CCTV | Detector type IS 2189:2026 describes | Limitation |
|---|---|---|---|---|
| Cotton or yarn-waste godown | Alarms on a pile surface heating, by threshold or rate of rise (Axis WP §3.3) | Needs visible smoke or flame and light | Flame detectors suit "high-ceiling, open-spaced buildings such as warehouses" (§5.1.4.3) | Sees only the surface facing the lens, not inside a bale |
| Scrap and waste piles | Vendor names recycling sites and waste piles (Axis WP §3.3.1) | Daylight only, if smoke is visible | Flame detectors for outdoor areas where draughts keep smoke from detectors (§5.1.4.3) | Sun-heated metal and hot incoming loads look like hotspots |
| Coal, biomass or husk yard | Vendor names coal piles and silos (Axis WP §4) | Smoke is hard to separate from dust | Spark/ember detectors on a duct or conveyor (§5.1.4.1) | Fog and rain reduce accuracy (Axis WP §3.2) |
| LT panels, transformers | Vendor names switchgear and transformers (Axis WP §4) | Little use on a closed steel panel | Smoke detection per NBC 4.9 | Shiny metal (emissivity 0.6 or lower) reads wrong (Axis WP §2.3) |
| Battery storage | Watches cabinet and rack surfaces | Smoke appears late | Classify the area first: explosion-proof CCTV and PESO | Cells sit inside cabinets, out of the lens's line of sight |
The mapping is our engineering reading.
Radiometric vs non-radiometric: same sensor, different job
Axis puts it plainly: "temperature-calibrated thermal cameras, called thermometric cameras, can measure absolute temperatures, while surveillance-optimized thermal cameras show relative temperatures" (Q1961-TE datasheet, checked 15 Oct 2026). Only the radiometric kind can alarm at a set temperature.
| Spec (Axis datasheets, checked 15 Oct 2026) | AXIS Q1961-TE (radiometric) | AXIS Q1951-E (non-radiometric) |
|---|---|---|
| Sensor (pixels) | 384 × 288, 17 μm | 384 × 288, 17 μm |
| Spectral range (μm) | 8–14 | 8–14 |
| Object temperature range (°C) | −40 to 350 | no thermometry |
| Accuracy | ±5 °C below 120 °C; ±15% above | not applicable |
| Fire analytic | Early fire detection | none listed |
| Lenses, HFOV (°) | 7 mm 55°; 13 mm 28° | 7 mm 55° to 35 mm 10.5° |
| Operating temperature (°C) | −40 to 60 | −40 to 60 |
A threshold alarm triggers on the highest, lowest or average temperature in a polygon. A rate alarm triggers if the temperature "increases or decreases too quickly" (Axis white paper §3.3.1).
Axis early fire detection filters out moving hot objects, but an object still for more than 30 seconds is treated as static and can alarm (§3.3.2). A forklift with a hot engine, parked in view, can then alarm.
What India's code says
NBC 2016 Part 4 does not mention video or thermal-imaging detection (full text searched, checked 15 Oct 2026). Clause 2.4 defines automatic detection as "automatically detecting smoke, heat or fire". Clause 4.9(g) requires the detection system to follow "accepted standards [4(15)]": IS 2175 and IS/ISO 7240-5 (heat), IS/ISO 7240-7, -15 and IS 11360 (smoke), IS/ISO 7240-11 (manual call points). Detector selection follows "good practice [4(16)]", listed as IS 2189:2008. The only CCTV mention, clause 3.4.12(b), lets CCTV be monitored from the fire command centre.
For most factories the NBC table is not final. Table 7 Note 17 says the Group G figures "are for small scale industry units"; for other industries requirements are worked out from Indian Standards "and also in consultation with the local fire authorities".
IS 2189:2026 now names video fire detectors. Table 1 lists "Video fire detectors" under IS/ISO 7240 Part 29 (2017), and the inspection table checks "video image smoke and fire detectors" quarterly (IS 2189:2026, checked 15 Oct 2026).
Two clauses rule out the shortcut. Clause 4.1: alarm equipment and cables "shall be independent of any other system or cables, and shall not be shared with any other system". A camera on your CCTV LAN and NVR fails that. The foreword adds that automatic detection is "not considered a substitute for automatic sprinklers".
No thermal hotspot detector type appears in IS 2189:2026 Table 1 (checked 15 Oct 2026). The NOC side is covered in what fire NOC inspectors look for.
Where the standards differ abroad
| Scheme | What is recognised | Source (checked 15 Oct 2026) |
|---|---|---|
| India, IS 2189:2026 | Video fire detectors to IS/ISO 7240-29:2017 | Table 1 |
| France, CNPP Cert. | "Thermal camera heat detection systems" as a certified category; Hikvision DS-2TD2137T, 2167T, 2637T, 2667T, 4137T, 4167T, effective 30 Mar 2023, validity ended 29 Mar 2026 on this copy | CNPP 32.20.221, 33.20.221 |
The CNPP certificates describe the systems as "associable with power supply compliant with EN54-4", the European fire-alarm power-supply standard. Where a thermal camera counts as a heat detector, it is a certified model with a fire-grade supply, not an off-the-shelf CCTV camera.
Sizing: how far can the camera see a hotspot
Axis recommends a monitored object cover at least 10 × 10 pixels of the 384 × 288 sensor (Q1961-TE datasheet). With R = 384 px:
d_max = s × R ÷ (10 × 2 × tan(HFOV/2)), where s is hotspot size in metres.
| Hotspot size (m) | 7 mm, 55° HFOV: max distance (m) | 13 mm, 28° HFOV: max distance (m) |
|---|---|---|
| 0.1 | 3.7 | 7.7 |
| 0.3 | 11.1 | 23.1 |
| 0.5 | 18.4 | 38.5 |
| 1.0 | 36.9 | 77.0 |
Worked example (assumed layout): a 40 m × 20 m cotton-waste godown, camera on a short wall. A 0.3 m hotspot 40 m away is beyond both lenses; the 13 mm reaches 23.1 m. Two 7 mm cameras, one per 20 m half, cover the full width (20.8 m at 20 m) and catch hotspots of about 0.54 m (20 ÷ 36.9). For 0.3 m at 20 m the 13 mm qualifies, but it covers only 10 m of width there, so plan four. Check positions in the lens and DORI calculator.
Certified models and ₹. Mama's dataset of 2,229 primary STQC ER and BIS CRS rows contains zero thermal or bi-spectrum models (name and type search; checked 15 Oct 2026). Check any quoted model in the Certified CCTV Finder. No INR price list for fixed thermal cameras was found from Axis or Hikvision India (checked 15 Oct 2026); budget from written quotes.
What breaks in a factory
- Shiny metal. Bare copper reads low; Axis cameras work best above emissivity 0.9 and only "may be considered" above 0.5 (white paper §2.3).
- Roof heat. The Q1961-TE is rated to 60 °C. Under an uninsulated May roof, measure the mounting point first.
- Lint on the window. Clean it weekly.
- Hot process loads. Castings or freshly dried yarn entering a store trip a fixed threshold. Use rate-of-rise and exclude the doorway.
- Power. Put the PoE switch on UPS.
When to call the installer / what to ask the vendor
- "Is this model radiometric? Send the datasheet line with temperature range and accuracy."
- "What is the smallest hotspot your design catches at our farthest point?" Ask for the 10 × 10 pixel arithmetic.
- "Is the fire analytic certified by any fire body for this model and firmware?" Ask for the certificate.
- "How does the alarm reach a person at 2 a.m.?" Relay into the fire panel input, a siren, or only an app?
Where Mama fits
Mama reads existing cameras over RTSP/ONVIF to report machine idle time to the owner. It is not a fire detector. For a camera plan, leave an email or phone in the form below. More at askthemama.com.
FAQ
Can a thermal camera detect fire before a smoke detector?
For a surface in its view, it can: Axis describes early fire detection as catching "a smoldering fire before it spreads". It cannot see inside a bale or a closed panel. Smoke and heat detectors remain the system NBC 2016 Part 4 clause 4.9 requires.
Is video fire detection approved in India?
IS 2189:2026 lists video fire detectors conforming to IS/ISO 7240-29 as an alarm component, inspected quarterly. They must be independent of any other system (clause 4.1), so analytics on your CCTV NVR does not qualify. Thermal hotspot cameras are not listed (checked 15 Oct 2026).
What is the difference between radiometric and non-radiometric thermal cameras?
A radiometric camera is temperature-calibrated: the AXIS Q1961-TE reads −40 °C to 350 °C, ±5 °C below 120 °C. A non-radiometric camera such as the AXIS Q1951-E shows relative heat for detecting people and vehicles. Only the radiometric kind can alarm at a set temperature.