Infrared Emissivity Table

Emissivity Reference Table & Definition

Summary: Emissivity is a measure (from 0 to 1) of a material's efficiency in emitting thermal energy. Most organic materials (food, skin, water) have high emissivity (~0.95), while shiny metals have low emissivity. This guide includes a comprehensive table of common emissivity values for calibrating your infrared thermometer.

What is Emissivity?

Emissivity is a measure of the efficiency in which a surface emits thermal energy. It is defined as the fraction of energy being emitted relative to that emitted by a thermally black surface (a "black body").

• Black Body (Value = 1.0): A material that is a perfect emitter of heat energy.
• Thermal Mirror (Value = 0.0): A material that reflects all energy and emits none.

Example: If an object has the potential to emit 100 units of energy but only emits 90 units in the real world, its emissivity value is 0.90. In the real world, there are no perfect black bodies and very few perfect mirrors, so most objects fall somewhere between 0 and 1.

Accuracy of These Values

Important Note: The emissivity of a surface will alter based on texture, color, and actual temperature. It is almost impossible to guarantee exact figures for every material.

• Recommendation: For critical accuracy, we recommend comparing your infrared measurement against a reading found with an accurate Surface Probe (contact thermometer). Once the true temperature is known, you can adjust your infrared thermometer's emissivity setting to match.

No responsibility can be assumed by ThermoWorks for the accuracy or otherwise of the following figures.

Table of Emissivity Values

Use the values below as a starting point for adjusting your infrared thermometer.

Material	Emissivity Value
Aluminum: anodized	0.77
Aluminum: polished	0.05
Asbestos: board	0.96
Asbestos: fabric	0.78
Asbestos: paper	0.93
Asbestos: slate	0.96
Brass: highly polished	0.03
Brass: oxidized	0.61
Brick: common	0.81 - 0.86
Brick: common, red	0.93
Brick: facing, red	0.92
Brick: fireclay	0.75
Brick: masonry	0.94
Brick: red	0.90
Carbon: candle soot	0.95
Carbon: graphite, filed surface	0.98
Carbon: purified	0.80
Cement	0.54
Charcoal: powder	0.96
Chipboard: untreated	0.90
Chromium: polished	0.10
Clay: fired	0.91
Concrete	0.92
Concrete: dry	0.95
Concrete: rough	0.92 - 0.97
Copper: polished	0.05
Copper: oxidized	0.65
Enamel: lacquer	0.90
Fabric: Hessian, green	0.88
Fabric: Hessian, uncolored	0.87
Fiberglass	0.75
Fiber board: porous, untreated	0.85
Fiber board: hard, untreated	0.85
Filler: white	0.88
Firebrick	0.68
Food & Organic Materials	0.95 - 0.97
Formica	0.94
Galvanized Pipe	0.46
Glass	0.92
Glass: chemical ware (partly transparent)	0.97
Glass: frosted	0.70 - 0.96
Glass: polished plate	0.94
Granite: natural surface	0.96
Graphite: powder	0.97
Gravel	0.28
Gypsum	0.85
Hardwood: across grain	0.82
Hardwood: along grain	0.68 - 0.73
Ice	0.97
Iron: heavily rusted	0.91 - 0.96
Lacquer: Bakelite	0.93
Lacquer: dull black	0.97
Lampblack	0.96
Limestone: natural surface	0.96
Mortar	0.87
Mortar: dry	0.94
P.V.C.	0.91 - 0.93
Paint: 3M, black velvet coating 9560	1.00
Paint: aluminum	0.45
Paint, oil: average of 16 colors	0.94
Paint: oil, black, flat	0.94
Paint: oil, black, gloss	0.92
Paint: oil, grey, flat	0.97
Paint: oil, grey, gloss	0.94
Paint: oil, various colors	0.94
Paint: plastic, black	0.95
Paint: plastic, white	0.84
Paper: black	0.90
Paper: black, dull	0.94
Paper: black, shiny	0.90
Paper: cardboard box	0.81
Paper: green	0.85
Paper: red	0.76
Paper: white	0.68
Paper: white bond	0.93
Paper: yellow	0.72
Paper: tar	0.92
Pipes: glazed	0.83
Plaster	0.86 - 0.90
Plaster: rough coat	0.91
Plasterboard: untreated	0.90
Plastic: acrylic, clear	0.94
Plastic: black	0.95
Plastic: white	0.84
Plastic paper: red	0.94
Plastic paper: white	0.84
Plexiglass: Perspex	0.86
Plywood	0.83 - 0.98
Plywood: commercial, smooth finish, dry	0.82
Plywood: untreated	0.83
Polypropylene	0.97
Porcelain: glazed	0.92
Quartz	0.93
Redwood: wrought, untreated	0.83
Redwood: unwrought, untreated	0.84
Rubber	0.95
Rubber: stopper, black	0.97
Sand	0.90
Skin, human	0.95 - 0.98
Snow	0.80
Soil: dry	0.92
Soil: frozen	0.93
Soil: saturated with water	0.95
Stainless Steel	0.59
Stainless Plate	0.34
Steel: galvanized	0.28
Steel: rolled freshly	0.24
Styrofoam: insulation	0.60
Tape: electrical, insulating, black	0.97
Tape: masking	0.92
Tile: floor, asbestos	0.94
Tile: glazed	0.94
Tin: burnished	0.05
Tin: commercial tin-plated sheet iron	0.06
Varnish: flat	0.93
Wallpaper: slight pattern, light grey	0.85
Wallpaper: slight pattern, red	0.90
Water	0.95
Water: distilled	0.95
Water: ice, smooth	0.96
Water: frost crystals	0.98
Water: snow	0.85
Wood: planed	0.90
Wood: paneling, light finish	0.87
Wood: spruce, polished, dry	0.86