Dew Point InfraRed Thermometer With Audio/Visual Alarm

Quick Answer: The Dew Point InfraRed Thermometer With Audio/Visual Alarm is a handheld instrument that measures surface temperature without contact, measures the air temperature and humidity around it, calculates the dew point, and signals with a sound and a light when a surface is close enough to the dew point for condensation to form.

Surface Temperature Against Dew Point

Condensation appears on a surface when that surface is colder than the dew point of the air touching it. A plain infrared thermometer tells you only how cold the wall, pipe or window is. This instrument adds sensors for air temperature and relative humidity, works out the dew point from them, and compares the two figures as you scan. When the gap narrows to the warning level, the audio and visual alarm tells you without your having to read numbers.

That makes it a fast survey tool for finding the cold spots where damp and mould start: wall corners, window reveals, uninsulated pipes, the backs of cupboards on outside walls and the ceilings of cold stores. The same check is used before painting or coating steel or concrete, because a coating applied to a surface at or near the dew point traps moisture beneath it.

Infrared readings depend on emissivity, the efficiency with which a surface gives off infrared radiation. Painted walls, plaster, wood and most non-metals read well; shiny metal reads falsely low. The measured spot also grows with distance, so stand close enough that it falls wholly on the surface of interest. The alarm margin, emissivity setting and spot ratio for this dew point infrared thermometer are confirmed on request.

Applications

• Surveying buildings for condensation and mould risk on walls, ceilings and window frames
• Checking cold-room walls, chilled pipes and air-conditioning ducts for sweating
• Confirming that steel or concrete is safely above the dew point before coating
• Teaching dew point and condensation with real surfaces in physics or geography lessons

Specifications

Care & Handling

• Let the instrument acclimatise for several minutes when moved between rooms of different temperature and humidity, so its humidity sensor settles.
• Keep the infrared lens clean with a soft, dry cloth; smears reduce readings.
• If the unit has a laser pointer, never aim it at anyone’s eyes.
• Store it away from solvent vapour, which can upset humidity sensors.

Why Choose LabEquip

Building surveyors, facilities teams, cold-chain operators and physics or building-science departments use dew point IR thermometers to show exactly where condensation will form. LabEquip lists this instrument in its General Lab Products range, with a humidity and temperature meter with dew point for air-only readings; contact us for details.

Frequently Asked Questions

What is the dew point?

It is the temperature to which air must cool, at its current moisture content, for water vapour to start condensing. Any surface colder than the dew point of the air around it collects condensation.

How is this different from an ordinary infrared thermometer?

An ordinary infrared thermometer measures surface temperature only. This one also measures the air’s temperature and humidity, calculates the dew point and alarms when a surface approaches it, so condensation risk is shown directly.

Why does a shiny metal pipe read too cold?

Shiny metal gives off little infrared radiation and reflects its surroundings, so the thermometer under-reads it. Put a strip of matt tape or paint on the pipe and measure that instead.

How close should I stand to the surface?

Close enough that the measuring spot falls entirely on the surface you want. The spot grows with distance, so from far away the reading averages the target with its surroundings.

Why check the dew point before painting?

Paint and coatings applied to a surface at or near the dew point trap a film of moisture, which can cause poor adhesion and blistering. Coating specifications set how far above the dew point the surface must be.

Can the alarm level be changed?

Many dew point thermometers allow the warning margin to be adjusted. Whether this model does, and its default setting, should be confirmed before purchase.

Last Updated: September 2026