Emissivity is one of the most important parameters in thermal imaging technology if you want to get an accurate temperature measurement. The emissivity value varies with the material type, surface finish condition, etc. There are some techniques to get the actual emissivity for the object to be thermally imaged. Here is the emissivity list for most materials in general. 

What Is Emissivity in Infrared Thermal Imaging?

Emissivity is a value measuring how efficiently a surface is able to emit infrared thermal radiation. It is measured as the fraction of infrared radiation being emitted relative to the radiation emitted by an ideal black body. A black body can emit 100% infrared radiation and has an emissivity of 1. A perfect thermal mirror is a material with the emissivity value of 0. In reality, the material emissivity is between 0 and 1. 

Accuracy of Object Emissivity Values in Infrared Thermal Imaging

As the emissivity value of an object surface varies with material texture and surface finish, and with the actual temperature at the time of inspection. The comparison method is recommended if an accurate emissivity value desired. 

The following emissivity table lists the most common material with the limited surface condition for general use in infrared thermal imaging cameras. Some infrared thermal imager cameras have the built-in list inside the camera for you to easily define the regions and pick up the appropriate emissivity for each region, such as FOTRIC 346A thermal camera. 

List of Emissivity of Materials in Infrared Thermal Imaging

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	.81-.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	.92-.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
Formica	0.94
Galvanized Pipe	0.46
Glass	0.92
Glass: chemical ware (partly transparent)	0.97
Glass: frosted	0.96
Glass: frosted	0.70
Glass: polished plate	0.94
Granite: natural surface	0.96
Graphite: powder	0.97
Gravel	0.28
Gypsum	0.08
Hardwood: across grain	0.82
Hardwood: along grain	.68-.73
Ice	0.97
Iron: heavily rusted	.91-.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.	.91-.93
Paint: 3M, black velvet coating 9560 series optical black	@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	.86-.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: Perplex	0.86
Plywood	.83-.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	0.98
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