No - it watches for the radiation a flame emits rather than sensing anything in the atmosphere.

It answers a different question: whether a release has already ignited.

Gas detection warns before ignition and allows shutdown and evacuation.

Flame detection responds immediately after ignition and triggers suppression.

Serious installations use both, because either alone leaves a gap.

They are grouped together because they protect the same hazards and share controllers.

They watch different parts of the spectrum and have different false alarm vulnerabilities.

Ultraviolet detectors respond very fast but are susceptible to arc welding, lightning and some lamps.

Infrared detectors watch the characteristic flicker of hydrocarbon flames and resist many of those sources.

Combined UV/IR detectors require agreement between channels before alarming.

Multi-spectrum infrared compares several infrared bands to confirm a real flame.

Modern installations use the combined approaches to get speed and false-alarm immunity together.

Because a flame detector that cries wolf gets disabled, and a disabled detector protects nothing.

Hot work, sunlight reflections, vehicle exhausts, heaters and welding are all present in these environments.

Each false alarm erodes confidence and increases the chance of the next one being ignored.

Manufacturers publish immunity data for common false alarm sources.

Positioning away from known sources is as important as the technology choice.

Where hot work is routine, inhibit procedures are used rather than leaving detectors to alarm.

A flame detector sees a cone, so positioning determines what is actually protected.

An obstruction anywhere in that cone creates a blind area.

Unlike a gas detector, it cannot detect around a corner or behind equipment.

Detection distance reduces towards the edge of the field of view.

Coverage is usually mapped during design rather than assumed from detector count.

Plant modifications that add equipment can create blind areas without anyone touching the detector.

An automatic periodic check that the lens path is clear, which turns a silent failure into a reported one.

Dirt, salt, oil mist and ice all block the radiation the detector depends on.

A contaminated lens reduces sensitivity without any external indication.

The test verifies the optical path and reports a fault when it degrades.

It does not replace physical cleaning, but it tells you when cleaning is needed.

Instruments without it rely entirely on the cleaning schedule being kept.

Far faster than heat or smoke detection - typically within seconds of a flame appearing.

That speed is what allows automatic suppression to be triggered usefully.

Response time depends on flame size, fuel type and distance.

Manufacturers state detection distances for specified fire sizes and fuels.

Some applications deliberately introduce a short delay or require two detectors to agree before executive action.

That trades a little speed for a large reduction in false discharges.

Lens cleaning, functional testing with a test source, and verification of the field of view.

Cleaning frequency depends entirely on the environment.

Functional testing uses a test lamp or source appropriate to the technology.

Field of view should be re-checked after any plant modification.

Alignment can drift if the mounting is subject to vibration.

Intervals and records follow the local regime as with any life safety system.