 |
Infrared
Emissivity |
 |
1 Emissivity table introductory comment
Understanding an object's emissivity, or its characteristic
"radiance" is a critical component in the proper handling
of infrared measurements. Concisely, emissivity is the ratio
of radiation emitted by a surface or blackbody and its theoretical
radiation predicted from Planck's law. [W(L,T)=C1/(L^5*(exp(C2/LT)-1)]
A material's surface emissivity is measured by the amount of
energy emitted when the surface is directly observed. There
are many variables that affect a specific object's emissivity,
such as the wavelength of interest, field of view, the geometric
shape of the blackbody, and temperature. However, for the purposes
and applications of the infrared thermometer user, a comprehensive
table showing the emissivity at corresponding temperatures of
various surfaces and objects is displayed. For a more detailed
and technical presentation of emissitivty, please contact ZyTemp
directly. |
 |
 |
Material
(Non Metal) |
|
|
 |
 |
 |
 |
 |
|
Material(Non-Metals) |
Temp degF(degC) |
Emissivity |
|
Adobe
|
68 (20)
|
0.9
|
|
Asbestos
|
|
ˇˇ
|
Board
|
100 (38)
|
0.96
|
|
ˇˇ
|
Cement
|
32-392 (0-200)
|
0.96
|
|
ˇˇ
|
Cement, Red
|
2500 (1371)
|
0.67
|
|
ˇˇ
|
Cement, White
|
2500 (1371)
|
0.65
|
|
ˇˇ
|
Cloth
|
199 (93)
|
0.9
|
|
ˇˇ
|
Paper
|
100-700 (38-371)
|
0.93
|
|
ˇˇ
|
Slate
|
68 (20)
|
0.97
|
|
ˇˇ
|
Asphalt, pavement
|
100 (38)
|
0.93
|
|
ˇˇ
|
Asphalt, tar paper
|
68 (20)
|
0.93
|
|
Basalt
|
68 (20)
|
0.72
|
|
Brick
|
|
ˇˇ
|
Red, rough
|
70 (21)
|
0.93
|
|
ˇˇ
|
Gault Cream
|
2500-5000 (1371-2760)
|
.26-.30
|
|
ˇˇ
|
Fire Clay
|
2500 (1371)
|
0.75
|
|
ˇˇ
|
Light Buff
|
1000 (538)
|
0.8
|
|
ˇˇ
|
Lime Clay
|
2500 (1371)
|
0.43
|
|
ˇˇ
|
Fire Brick
|
1832 (1000)
|
.75-.80
|
|
ˇˇ
|
Magnesite, Refractory
|
1832 (1000)
|
0.38
|
|
ˇˇ
|
Grey Brick
|
2012 (1100)
|
0.75
|
|
ˇˇ
|
Silica, Glazed
|
2000 (1093)
|
0.88
|
|
ˇˇ
|
Silica, Unglazed
|
2000 (1093)
|
0.8
|
|
ˇˇ
|
Sandlime
|
2500-5000 (1371-2760)
|
.59-.63
|
|
Carborundum
|
1850 (1010)
|
0.92
|
|
Ceramic
|
|
ˇˇ
|
Alumina on Inconel
|
800-2000 (427-1093)
|
.69-.45
|
|
ˇˇ
|
Earthenware, Glazed
|
70 (21)
|
0.9
|
|
ˇˇ
|
Earthenware, Matte
|
70 (21)
|
0.93
|
|
ˇˇ
|
Greens No. 5210-2C
|
200-750 (93-399)
|
.89-.82
|
|
ˇˇ
|
Coating No. C20A
|
200-750 (93-399)
|
.73-.67
|
|
ˇˇ
|
Porcelain
|
72 (22)
|
0.92
|
|
ˇˇ
|
White Al2O3
|
200 (93)
|
0.9
|
|
ˇˇ
|
Zirconia on Inconel
|
800-2000 (427-1093)
|
.62-.45
|
|
Clay
|
68 (20)
|
0.39
|
|
ˇˇ
|
Fired
|
158 (70)
|
0.91
|
|
ˇˇ
|
Shale
|
68 (20)
|
0.69
|
|
ˇˇ
|
Tiles, Light Red
|
2500-5000 (1371-2760)
|
.32-.34
|
|
ˇˇ
|
Tiles, Red
|
2500-5000 (1371-2760)
|
.40-.51
|
|
ˇˇ
|
Tiles,Dark Purple
|
2500-5000 (1371-2760)
|
0.78
|
|
Concrete
|
|
ˇˇ
|
Rough
|
32-2000 (0-1093)
|
0.94
|
|
ˇˇ
|
Tiles, Natural
|
2500-5000 (1371-2760)
|
.63-.62
|
|
ˇˇ
|
Brown
|
2500-5000 (1371-2760)
|
.87-.83
|
|
ˇˇ
|
Black
|
2500-5000 (1371-2760)
|
.94-.91
|
|
Cotton Cloth
|
68 (20)
|
0.77
|
|
Dolomite Lime
|
68 (20)
|
0.41
|
|
Emery Corundum
|
176 (80)
|
0.86
|
|
Glass
|
|
ˇˇ
|
Convex D
|
212 (100)
|
0.8
|
|
ˇˇ
|
Convex D
|
600 (316)
|
0.8
|
|
ˇˇ
|
Convex D
|
932 (500)
|
0.76
|
|
ˇˇ
|
Nonex
|
212 (100)
|
0.82
|
|
ˇˇ
|
Nonex
|
600 (316)
|
0.82
|
|
ˇˇ
|
Nonex
|
932 (500)
|
0.78
|
|
ˇˇ
|
Smooth
|
32-200(0-93)
|
.92-.94
|
|
Granite
|
70 (21)
|
0.45
|
|
Gravel
|
100 (38)
|
0.28
|
|
Gypsum
|
68 (20)
|
.80-.90
|
|
Ice, Smooth
|
32 (0)
|
0.97
|
|
Ice, Rough
|
32 (0)
|
0.98
|
|
Lacquer
|
|
ˇˇ
|
Black
|
200 (93)
|
0.96
|
|
ˇˇ
|
Blue, on Al Foil
|
100 (38)
|
0.78
|
|
ˇˇ
|
Clear, on Al Foil
(2 coats)
|
200 (93)
|
.08-.09
|
|
ˇˇ
|
Clear, on Bright Cu
|
200 (93)
|
0.66
|
|
ˇˇ
|
Clear, on Tarnished
Cu
|
200 (93)
|
0.64
|
|
ˇˇ
|
Red, on Al Foil (2
coats)
|
100 (38)
|
.60-.74
|
|
ˇˇ
|
White
|
200 (93)
|
0.95
|
|
ˇˇ
|
White, on Al Foil
(2 coats)
|
100 (38)
|
.69-.88
|
|
ˇˇ
|
Yellow, on Al Foil
(2 coats)
|
100 (38)
|
.57-.79
|
|
Lime Mortar
|
100-500 (38-260)
|
.90-.92
|
|
Limestone
|
100 (38)
|
0.95
|
|
Marble, White
|
100 (38)
|
0.95
|
|
ˇˇ
|
Smooth, White
|
100 (38)
|
0.56
|
|
ˇˇ
|
Polished Grey
|
100 (38)
|
0.75
|
|
Mica
|
100 (38)
|
0.75
|
|
Oil on Nickel
|
|
ˇˇ
|
0.001 Film
|
72 (22)
|
0.27
|
|
ˇˇ
|
0.002 "
|
72 (22)
|
0.46
|
|
ˇˇ
|
0.005 "
|
72 (22)
|
0.72
|
|
ˇˇ
|
Thick "
|
72 (22)
|
0.82
|
|
Oil, Linseed
|
|
ˇˇ
|
On Al Foil, uncoated
|
250 (121)
|
0.09
|
|
ˇˇ
|
On Al Foil, 1 coat
|
250 (121)
|
0.56
|
|
ˇˇ
|
On Al Foil, 2 coats
|
250 (121)
|
0.51
|
|
ˇˇ
|
On Polished Iron,
.001 Film
|
100 (38)
|
0.22
|
|
ˇˇ
|
On Polished Iron,
.002 Film
|
100 (38)
|
0.45
|
|
ˇˇ
|
On Polished Iron,
.004 Film
|
100 (38)
|
0.65
|
|
ˇˇ
|
On Polished Iron,
Thick Film
|
100 (38)
|
0.83
|
|
Paints
|
|
ˇˇ
|
Blue, Cu2O3
|
75 (24)
|
0.94
|
|
ˇˇ
|
Black, CuO
|
75 (24)
|
0.96
|
|
ˇˇ
|
Green, Cu2O3
|
75 (24)
|
0.92
|
|
ˇˇ
|
Red, Fe2O3
|
75 (24)
|
0.91
|
|
ˇˇ
|
White, Al2O3
|
75 (24)
|
0.94
|
|
ˇˇ
|
White, Y2O3
|
75 (24)
|
0.9
|
|
ˇˇ
|
White, ZnO
|
75 (24)
|
0.95
|
|
ˇˇ
|
White, MgCO3
|
75 (24)
|
0.91
|
|
ˇˇ
|
White, ZrO2
|
75 (24)
|
0.95
|
|
ˇˇ
|
White, ThO2
|
75 (24)
|
0.9
|
|
ˇˇ
|
White, MgO
|
75 (24)
|
0.91
|
|
ˇˇ
|
White, PbCO3
|
75 (24)
|
0.93
|
|
ˇˇ
|
Yellow, PbO
|
75 (24)
|
0.9
|
|
ˇˇ
|
Yellow, PbCrO4
|
75 (24)
|
0.93
|
|
Paints, Aluminium
|
100 (38)
|
.27-.67
|
|
ˇˇ
|
10% Al
|
100 (38)
|
0.52
|
|
ˇˇ
|
26% Al
|
100 (38)
|
0.3
|
|
ˇˇ
|
Dow XP-310
|
200 (93)
|
0.22
|
|
Paints, Bronze
|
Low
|
.34-.80
|
|
ˇˇ
|
Gum Varnish (2 coats)
|
70 (21)
|
0.53
|
|
ˇˇ
|
Gum Varnish (3 coats)
|
70 (21)
|
0.5
|
|
ˇˇ
|
Cellulose Binder (2
coats)
|
70 (21)
|
0.34
|
|
Paints, Oil
|
|
ˇˇ
|
All colours
|
200 (93)
|
.92-.96
|
|
ˇˇ
|
Black
|
200 (93)
|
0.92
|
|
ˇˇ
|
Black Gloss
|
70 (21)
|
0.9
|
|
ˇˇ
|
Camouflage Green
|
125 (52)
|
0.85
|
|
ˇˇ
|
Flat Black
|
80 (27)
|
0.88
|
|
ˇˇ
|
Flat White
|
80 (27)
|
0.91
|
|
ˇˇ
|
Grey-Green
|
70 (21)
|
0.95
|
|
ˇˇ
|
Green
|
200 (93)
|
0.95
|
|
ˇˇ
|
Lamp Black
|
209 (98)
|
0.96
|
|
ˇˇ
|
Red
|
200 (93)
|
0.95
|
|
ˇˇ
|
White
|
200 (93)
|
0.94
|
|
Quartz, Rough, Fused
|
70 (21)
|
0.93
|
|
ˇˇ
|
Glass, 1.98 mm
|
540 (282)
|
0.9
|
|
ˇˇ
|
Glass, 1.98 mm
|
1540 (838)
|
0.41
|
|
ˇˇ
|
Glass, 6.88 mm
|
540 (282)
|
0.93
|
|
ˇˇ
|
Glass, 6.88 mm
|
1540 (838)
|
0.47
|
|
ˇˇ
|
Opaque
|
570 (299)
|
0.92
|
|
ˇˇ
|
Opaque
|
1540 (838)
|
0.68
|
|
Red Lead
|
212 (100)
|
0.93
|
|
Rubber, Hard
|
74 (23)
|
0.94
|
|
Rubber, Soft, Grey
|
76 (24)
|
0.86
|
|
Sand
|
68 (20)
|
0.76
|
|
Sandstone
|
100 (38)
|
0.67
|
|
Sandstone, Red
|
100 (38)
|
.60-.83
|
|
Sawdust
|
68 (20)
|
0.75
|
|
Shale
|
68 (20)
|
0.69
|
|
Silica,Glazed
|
1832 (1000)
|
0.85
|
|
Silica, Unglazed
|
2012 (1100)
|
0.75
|
|
Silicon Carbide
|
300-1200 (149-649)
|
.83-.96
|
|
Silk Cloth
|
68 (20)
|
0.78
|
|
Slate
|
100 (38)
|
.67-.80
|
|
Snow, Fine Particles
|
20 (-7)
|
0.82
|
|
Snow, Granular
|
18 (-8)
|
0.89
|
|
Soil
|
|
ˇˇ
ˇˇ
ˇˇ
|
Surface
|
100 (38)
|
0.38
|
|
Black Loam
|
68 (20)
|
0.66
|
|
Plowed Field
|
68 (20)
|
0.38
|
|
Soot
|
|
ˇˇ
ˇˇ
ˇˇ
ˇˇ
|
Acetylene
|
75 (24)
|
0.97
|
|
Camphor
|
75 (24)
|
0.94
|
|
Candle
|
250 (121)
|
0.95
|
|
Coal
|
68 (20)
|
0.95
|
|
Stonework
|
100 (38)
|
0.93
|
|
Water
|
100 (38)
|
0.67
|
|
Waterglass
|
68 (20)
|
0.96
|
|
Wood
|
Low
|
.80-.90
|
|
Beech Planed
|
158 (70)
|
0.94
|
|
Oak, Planed
|
100 (38)
|
0.91
|
|
Spruce, Sanded
|
100 (38)
|
0.89
|
|
|
|
|
|
|
 |
 |
 |
 |
|
|
EMS
Histogram of NonMetal |
|
|
|
|
|
|
|
Material(metal) |
Temp degF (degC) |
Emissivity |
|
Alloys
|
|
ˇˇ
|
20-Ni,
24-CR, 55-FE, Oxid.
|
392
(200)
|
0.9
|
|
ˇˇ
|
20-Ni,
24-CR, 55-FE, Oxid.
|
932(500)
|
0.97
|
|
ˇˇ
|
60-Ni,
12-CR, 28-FE, Oxid.
|
518
(270)
|
0.89
|
|
ˇˇ
|
60-Ni,
12-CR, 28-FE, Oxid.
|
1040
(560)
|
0.82
|
|
ˇˇ
|
80-Ni,
20-CR, Oxidised
|
212
(100)
|
0.87
|
|
ˇˇ
|
80-Ni,
20-CR, Oxidised
|
1112
(600)
|
0.87
|
|
ˇˇ
|
80-Ni,
20-CR, Oxidised
|
2372
(1300)
|
0.89
|
|
Aluminium
|
|
ˇˇ
|
Unoxidised
|
77
(25)
|
0.02
|
|
ˇˇ
|
Unoxidised
|
212
(100)
|
0.03
|
|
ˇˇ
|
Unoxidised
|
932
(500)
|
0.06
|
|
ˇˇ
|
Oxidised
|
390
(199)
|
0.11
|
|
ˇˇ
|
Oxidised
|
1110
(599)
|
0.19
|
|
ˇˇ
|
Oxidised at 599degC(1110degF)
|
390
(199)
|
0.11
|
|
ˇˇ
|
Oxidised at 599degC(1110degF)
|
1110
(599)
|
0.19
|
|
ˇˇ
|
Heavily Oxidised
|
200
(93)
|
0.2
|
|
ˇˇ
|
Heavily Oxidised
|
940
(504)
|
0.31
|
|
ˇˇ
|
Highly Polished
|
212
(100)
|
0.09
|
|
ˇˇ
|
Roughly Polished
|
212
(100)
|
0.18
|
|
ˇˇ
|
Commercial Sheet
|
212
(100)
|
0.09
|
|
ˇˇ
|
Highly Polished Plate
|
440
(227)
|
0.04
|
|
ˇˇ
|
Highly Polished Plate
|
1070
(577)
|
0.06
|
|
ˇˇ
|
Bright Rolled Plate
|
338
(170)
|
0.04
|
|
ˇˇ
|
Bright Rolled Plate
|
932
(500)
|
0.05
|
|
ˇˇ
|
Alloy A3003, Oxidised
|
600
(316)
|
0.4
|
|
ˇˇ
|
Alloy A3003, Oxidised
|
900
(482)
|
0.4
|
|
ˇˇ
|
Alloy 1100-0
|
200-800
(93-427)
|
0.05
|
|
ˇˇ
|
Alloy 24ST
|
75
(24)
|
0.09
|
|
ˇˇ
|
Alloy 24ST, Polished
|
75
(24)
|
0.09
|
|
ˇˇ
|
Alloy 75ST
|
75
(24)
|
0.11
|
|
ˇˇ
|
Alloy 75ST, Polished
|
75
(24)
|
0.08
|
|
Bismuth, Bright
|
176
(80)
|
0.34
|
|
Bismuth, Unoxidised
|
77
(25)
|
0.05
|
|
Bismuth, Unoxidised
|
212
(100)
|
0.06
|
|
Brass
|
|
ˇˇ
|
73% Cu, 27% Zn, Polished
|
476
(247)
|
0.03
|
|
ˇˇ
|
73% Cu, 27% Zn, Polished
|
674
(357)
|
0.03
|
|
ˇˇ
|
62% Cu, 37% Zn, Polished
|
494
(257)
|
0.03
|
|
ˇˇ
|
62% Cu, 37% Zn, Polished
|
710
(377)
|
0.04
|
|
ˇˇ
|
83% Cu, 17% Zn, Polished
|
530
(277)
|
0.03
|
|
ˇˇ
|
Matte
|
68
(20)
|
0.07
|
|
ˇˇ
|
Burnished to Brown
Colour
|
68
(20)
|
0.4
|
|
ˇˇ
|
Cu-Zn, Brass Oxidised
|
392
(200)
|
0.61
|
|
ˇˇ
|
Cu-Zn, Brass Oxidised
|
752
(400)
|
0.6
|
|
ˇˇ
|
Cu-Zn, Brass Oxidised
|
1112
(600)
|
0.61
|
|
ˇˇ
|
Unoxidised
|
77
(25)
|
0.04
|
|
ˇˇ
|
Unoxidised
|
212
(100)
|
0.04
|
|
ˇˇ
|
Cadmium
|
77
(25)
|
0.02
|
|
Carbon
|
|
ˇˇ
|
Lampblack
|
77
(25)
|
0.95
|
|
ˇˇ
|
Unoxidised
|
77
(25)
|
0.81
|
|
ˇˇ
|
Unoxidised
|
212
(100)
|
0.81
|
|
ˇˇ
|
Unoxidised
|
932
(500)
|
0.79
|
|
ˇˇ
|
Candle Soot
|
250
(121)
|
0.95
|
|
ˇˇ
|
Filament
|
500
(260)
|
0.95
|
|
ˇˇ
|
Graphitized
|
212
(100)
|
0.76
|
|
ˇˇ
|
Graphitized
|
572
(300)
|
0.75
|
|
ˇˇ
|
Graphitized
|
932
(500)
|
0.71
|
|
Chromium
|
100
(38)
|
0.08
|
|
Chromium
|
1000
(538)
|
0.26
|
|
Chromium, Polished
|
302
(150)
|
0.06
|
|
Cobalt, Unoxidised
|
932
(500)
|
0.13
|
|
Cobalt, Unoxidised
|
1832
(1000)
|
0.23
|
|
Columbium, Unoxidised
|
1500
(816)
|
0.19
|
|
Columbium, Unoxidised
|
2000
(1093)
|
0.24
|
|
Copper
|
|
ˇˇ
|
Cuprous Oxide
|
100
(38)
|
0.87
|
|
ˇˇ
|
Cuprous Oxide
|
500
(260)
|
0.83
|
|
ˇˇ
|
Cuprous Oxide
|
1000
(538)
|
0.77
|
|
ˇˇ
|
Black, Oxidised
|
100
(38)
|
0.78
|
|
ˇˇ
|
Etched
|
100
(38)
|
0.09
|
|
ˇˇ
|
Matte
|
100
(38)
|
0.22
|
|
ˇˇ
|
Roughly Polished
|
100
(38)
|
0.07
|
|
ˇˇ
|
Polished
|
100
(38)
|
0.03
|
|
ˇˇ
|
Highly Polished
|
100
(38)
|
0.02
|
|
ˇˇ
|
Rolled
|
100
(38)
|
0.64
|
|
ˇˇ
|
Rough
|
100
(38)
|
0.74
|
|
ˇˇ
|
Molten
|
1000
(538)
|
0.15
|
|
ˇˇ
|
Molten
|
1970
(1077)
|
0.16
|
|
ˇˇ
|
Molten
|
2230
(1221)
|
0.13
|
|
ˇˇ
|
Nickel Plated
|
100-500
(38-260)
|
0.37
|
|
Dow Metal
|
0.4-600
(-18-316)
|
0.15
|
|
Gold
|
|
ˇˇ
|
Enamel
|
212
(100)
|
0.37
|
|
ˇˇ
|
Plate (.0001)
|
ˇˇ
|
ˇˇ
|
|
ˇˇ
|
Plate on .0005 Silver
|
200-750
(93-399)
|
.11-.14
|
|
ˇˇ
|
Plate on .0005 Nickel
|
200-750
(93-399)
|
.07-.09
|
|
ˇˇ
|
Polished
|
100-500
(38-260)
|
0.02
|
|
ˇˇ
|
Polished
|
1000-2000
(538-1093)
|
0.03
|
|
Haynes Alloy C,
|
|
ˇˇ
|
Oxidised
|
600-2000
(316-1093)
|
.90-.96
|
|
Haynes Alloy 25,
|
|
ˇˇ
|
Oxidised
|
600-2000
(316-1093)
|
.86-.89
|
|
Haynes Alloy X,
|
|
ˇˇ
|
Oxidised
|
600-2000
(316-1093)
|
.85-.88
|
|
Inconel Sheet
|
1000
(538)
|
0.28
|
|
Inconel Sheet
|
1200
(649)
|
0.42
|
|
Inconel Sheet
|
1400
(760)
|
0.58
|
|
Inconel X, Polished
|
75
(24)
|
0.19
|
|
Inconel B, Polished
|
75
(24)
|
0.21
|
|
Iron
|
|
ˇˇ
|
Oxidised
|
212
(100)
|
0.74
|
|
ˇˇ
|
Oxidised
|
930
(499)
|
0.84
|
|
ˇˇ
|
Oxidised
|
2190
(1199)
|
0.89
|
|
ˇˇ
|
Unoxidised
|
212
(100)
|
0.05
|
|
ˇˇ
|
Red Rust
|
77
(25)
|
0.7
|
|
ˇˇ
|
Rusted
|
77
(25)
|
0.65
|
|
ˇˇ
|
Liquid
|
2760-3220
(1516-1771)
|
.42-.45
|
|
Cast Iron
|
|
ˇˇ
|
Oxidised
|
390
(199)
|
0.64
|
|
ˇˇ
|
Oxidised
|
1110
(599)
|
0.78
|
|
ˇˇ
|
Unoxidised
|
212
(100)
|
0.21
|
|
ˇˇ
|
Strong Oxidation
|
40
(104)
|
0.95
|
|
ˇˇ
|
Strong Oxidation
|
482
(250)
|
0.95
|
|
ˇˇ
|
Liquid
|
2795
(1535)
|
0.29
|
|
Wrought Iron
|
|
ˇˇ
|
Dull
|
77
(25)
|
0.94
|
|
ˇˇ
|
Dull
|
660
(349)
|
0.94
|
|
ˇˇ
|
Smooth
|
100
(38)
|
0.35
|
|
ˇˇ
|
Polished
|
100
(38)
|
0.28
|
|
Lead
|
|
ˇˇ
|
Polished
|
100-500
(38-260)
|
.06-.08
|
|
ˇˇ
|
Rough
|
100
(38)
|
0.43
|
|
ˇˇ
|
Oxidised
|
100
(38)
|
0.43
|
|
ˇˇ
|
Oxidised at 1100
|
100
(38)
|
0.63
|
| |
