All materials emit, absorb and reflect radiant energy. Emissivity defines how well surfaces of different materials emit heat in the form of infrared energy, measured between 0 and 1. Below is a rough guide to the emissivity of different materials. However, when emissivity cannot be guaranteed, a more precise value must be determined by using an accurate probe to compare and adjust an infrared thermometer so that it provides accurate readings.
How to calculate the correct emissivity parameter?
With the emissivity rating of many common materials listed below, entering the correct emissivity value is as easy as looking at the chart.
However, the chart values are estimates only. The actual emissivity of a surface you are trying to measure will vary slightly depending on its color, thickness, and even temperature. Checking the accuracy of an infrared measurement may require a little more planning.
This is especially true when your infrared thermometer is set to lower emissivity values. Since low-e materials are by definition poor emitters of infrared energy, infrared thermometers amplify the levels of infrared radiation they detect when they perform their calculations. This can lead to increased slight errors and make temperature measurements at lower settings appear erratic.
There are two ways to handle this:
1. Use a surface probe and measuring device to help you determine the appropriate emissivity setting for your infrared thermometer.
2. Use a high-emissivity patch between the target surface and the infrared thermometer.
Fixed emissivity IR thermometers
Mini RayTemp infrared thermometer
Infrared thermometer RayTemp 2
Fixed emissivity is a setting on some infrared thermometers, usually 0.95 or 0.97, that attempts to simplify their operation while still leaving them suitable for most material surfaces, including almost all foods. Other infrared thermometers feature adjustable emissivity settings, allowing you to more precisely prepare your infrared thermometers for the type of surface being measured, especially when measuring non-organic surfaces.
Our range of infrared thermometers
Material and emissivity
| Aluminum: anodized | 0.77 | Brass: oxidized | 0.61 |
| Aluminium : poli | 0.05 | Brick: common | .81-.86 |
| Asbestos: board | 0.96 | Brick: common, red | 0.90 |
| Asbestos: fabric | 0.78 | Brick: facing, red | 0.92 |
| Asbestos: paper | 0.93 | Brick: refractory clay | 0.75 |
| Asbestos: slate | 0.96 | Brick: masonry | 0.94 |
| Brass: highly polished | 0.03 | Red brick | 0.90 |
| Carbon: candle soot | 0.95 | Copper: oxidized | 0.65 |
| Carbone : graphite, surface limée | 0.98 | Copper: polished | 0.05 |
| Carbon: purified | 0.80 | Enamel: lacquer | 0.90 |
| Cement | 0.54 | Fabric: burlap, green | 0.88 |
| Charcoal: powder | 0.96 | Fabric: burlap, colorless | 0.87 |
| Particleboard: untreated | 0.90 | Fiberglass | 0.75 |
| Chrome : poli | 0.10 | Fibreboard: porous, untreated | 0.85 |
| Clay: cooked | 0.91 | Fibreboard: hard, untreated | 0.85 |
| Concrete | 0.92 | Filling: white | 0.88 |
| Concrete: dry | 0.95 | Refractory brick | 0.68 |
| Gross cement | .92-.97 | Formica | 0.94 |
| Galvanized pipe | 0.46 | Gypsum | 0.8-0.9 |
| Glass | 0.92 | Hardwood: along the grain | 0.82 |
| Glass chemical articles (partially transparent) | 0.97 | Hardwood: along the grain | .68-.73 |
| Frosted glass | 0.96 | Ice | 0.97 |
| Frosted glass | 0.70 | Iron: heavily rusted | .91-.96 |
| Glass: polished plate | 0.94 | Lacquer: bakelite | 0.93 |
| Glass: polished | 0.025 | Lacquer: matte black | 0.97 |
| Or: not poly | 0.47 | Lampblack | 0.96 |
| Granite: natural surface | 0.96 | Limestone: natural surface | 0.96 |
| Granite: powder | 0.97 | Mortar | 0.87 |
| Gravel | 0.28 | Mortar: dry | 0.94 |
| PVC | .91-.93 | Paper: blond, white | 0.93 |
| Paint: 3M, black velvet coating series 9560 optical black | 1.00 | Paper: yellow | 0.72 |
| Paint: aluminum | 0.45 | Paper: tar | 0.92 |
| Paint: oil, average of 16 colors | 0.94 | Pipe: glazed | 0.83 |
| Paint: oil, matte black | 0.94 | Plaster | .86-.90 |
| Paint: oil, glossy black | 0.92 | Plaster: rough layer | 0.91 |
| Paint: oil, matt gray | 0.97 | Plasterboard: untreated | 0.90 |
| Paint: oil, glossy gray | 0.94 | Plastic: acrylic, transparent | 0.94 |
| Painting: oil, different colors | 0.94 | Plastic: black | 0.95 |
| Paint: plastic, black | 0.95 | Plastic: white | 0.84 |
| Paint: plastic, white | 0.84 | Plastic paper: red | 0.94 |
| Paper: black | 0.90 | Plastic paper: white | 0.84 |
| Paper: matte black | 0.94 | Plexiglas: Perpex | 0.86 |
| Paper: glossy black | 0.90 | Plywood | .83-.98 |
| Paper: cardboard box | 0.81 | Plywood: commercial, smooth finish, dry | 0.82 |
| Paper: transl | 0.85 | Plywood: untreated | 0.83 |
| Paper: red | 0.76 | Polypropylene | 0.97 |
| Paper: yellow | 0.72 | Porcelain: glazed | 0.92 |
| Quartz | 0.93 | Tape: electrical, insulating, black | 0.97 |
| Redwood: forged, untreated | 0.83 | Tape: masking | 0.92 |
| Redwood: raw, untreated | 0.84 | Tiling: floor, asbestos | 0.94 |
| Rubber | 0.95 | Tiling: glazed | 0.94 |
| Rubber, cap, black | 0.97 | Pewter: burnished | 0.05 |
| Sable | 0.90 | Tin: commercial tinned sheet | 0.06 |
| Human skin | 0.98 | Varnish: matte | 0.93 |
| Snow | 0.80 | Wallpaper: light pattern, light gray | 0.85 |
| Sun: sec | 0.92 | Water | 0.95 |
| Ground: frozen | 0.93 | Distilled water | 0.95 |
| Soil: saturated with water | 0.95 | Water: ice cold, smooth | 0.96 |
| Stainless steel | 0.59 | Water: Frost Crystals | 0.98 |
| Stainless steel plate | 0.34 | Water: snow | 0.85 |
| Galvanized steel | 0.28 | Wood: planed | 0.90 |
| Steel: freshly rolled | 0.24 | Wood: paneling, light finish | 0.87 |
| Polystyrene: insulation | 0.60 | Wood: spruce, polished, dry | 0.86 |
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