Emissivity Charts and How Does Emissivity Effect Thermal Infrared Imaging

in Infrared Camera Systems

Emissivity
Using an objects radiation to measure its temperature is more difficult than attaching a thermometer or thermocouple to it, although sometimes this is the only convenient way. Other times, it is only necessary to see large area heat patterns, and this is difficult to do with a thermometer or thermocouple. In these cases a person can resort to any of a number of radiation measuring devices which will give a temperature indication (bolometers, pyrometers, thermopiles, line scanners, Infrared viewers, and thermographic systems)

Measurement consideration tips

  • The way a surface appears in the visible is the way that surface will appear in the infrared as well.
  • Get close enough for an object to occupy a sizable section of the IR camera screen, focus on the object
  • Look at the object face on
  • move around the object while scanning with the IR camera in order to eliminate reflections
  • Try IR scanning on a windless day
  • The higher the ambient temperature, the better the reading
  • Watch out for the sun, for light, and for spectral absorption and emission.

Material

Temperature (F)

(C)

E-Emissivity

Adobe

68

20

0.90

Asbestos

 

 

 

Board

100

38

0.96

Cement

32-392

0-200

0.96

Cement, Red

2500

1371

0.67

Cement, White

2500

1317

0.65

Cloth

199

93

0.90

Paper

100-700

38-371

0.93

Slate

68

20

0.72

Asphalt, pavement

100

38

0.93

Asphalt, tar paper

68

20

0.93

Basalt

68

20

0.72

Brick

 

 

 

Red, rough

70

21

0.93

Gault Cream

2500-5000

1371-2760

.26-.30

Fire Clay

2500

1371

0.75

Lime Clay

2500

1371

0.43

Fire Brick

1832

100

.75-.80

Magnesite, Refractory

1832

1000

0.38

Gray Brick

2021

1100

0.75

Silica, Glazed

2000

1093

0.88

Silica, Unglazed

2000

1093

0.80

Sandlime

2500-5000

1371-2760

.59-.63

Carborundum

1850

1010

0.92

Ceramic

 

 

Alumina on Inconel

800-2000

427-1093

.69-.45

Earthenware, Glazed

70

21

0.90

Earthenware, Matte

70

21

0.93

Greens No. 5210-2C

200-750

93-399

.89-.82

Coating No. C20A

200-750

93-399

.73-.80

Porcelain

72

22

0.92

White Al2O3

200

93

0.90

Zirconia on Inconel

800-2000

427-1093

.62-.45

Clay

68

20

0.39

” Fired

158

70

0.91

” Shale

68

20

0.69

” Tiles, Light Red

2500-5000

1371-2760

.32-.34

” Tiles,  Dark Purple

2500-5000

1371-2760

0.78

Concrete

 

 

 

Rough

32-2000

0-1093

0.94

Tiles, Natural

2500-5000

1371-2760

.63-.62

” Brown

2500-5000

1371-2760

.87-.83

” 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

 

 

 

Convex D

212

100

0.80

Convex D

600

316

0.82

Convex D

932

500

0.76

Nonex

212

100

0.82

Nonex

939

500

0.76

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

 

 

 

Black

200

93

0.96

Blue, on Al Foil

100

38

0.78

Clear, on Al Foil (2 coats)

200

93

.08 (.09)

Clear, on Bright Cu

200

93

0.66

Clear, on Tarnished Cu

200

93

0.64

Red, on Al Foil (2 coats)

200

93

.61 (.74)

White

200

93

0.95

White, on Al Foil (2 coats)

100

38

.69 (.88)

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

” Smooth, White

100

38

0.56

” Polished Gray

100

38

0.75

Mica

100

38

0.75

Oil on Nickel

 

 

 

0.001 Film

72

22

0.27

0.002 “

72

22

0.46

0.005 “

72

22

0.72

Thick “

72

22

0.82

Oil, Linseed

 

 

 

On Al Foil, uncoated

250

121

0.09

On Al Foil, 1 coat

250

121

0.56

On Al Foil, 2 coats

250

121

0.56

On Polished Iron, .001 Film

100

38

0.22

On Polished Iron, .002 Film

100

38

0.45

On Polished Iron, .004 Film

100

38

0.65

On Polished Iron, Thick Film

100

38

0.83

Paints

 

 

 

Blue, Cu2O3

75

24

0.94

Black, CuO

75

24

0.96

Green, Cu2O3

75

24

0.92

Red, Fe2O3

75

24

0.91

White, Al2O3

75

24

0.94

White, Y2O3

75

24

0.90

White, ZnO

75

24

0.95

White, MgCO3

75

24

0.91

White, ZrO2

75

24

0.95

White, ThO2

75

24

0.90

White, MgO

75

24

0.91

White, PbCO3

75

24

0.93

Yellow, PbO

75

24

0.90

Yellow, PbCrO4

75

24

0.93

Paints, Aluminium

100

38

.27-.67

10% Al

100

38

0.52

26% Al

100

38

0.30

Dow XP-310

200

93

0.22

Paints, Bronze

low

low

.34-.80

Gum Varnish (2 coats)

70

21

0.53

Gum Varnish (3 coats)

70

21

0.50

Cellulose Binder (2 coats)

70

21

0.34

Paints, Oil

 

 

 

All colors

200

93

.92-.96

Black

200

93

0.92

Black Gloss

70

21

0.90

Camouflage Green

125

52

0.85

Flat Black

80

27

0.88

Flat White

80

27

0.91

Gray-Green

70

21

0.95

Green

200

93

0.95

Lamp Black

209

98

0.96

Red

200

93

0.95

White

200

93

0.94

Quartz, Rough, Fused

70

21

0.93

Glass, 1.98 mm

540

282

0.90

Glass, 1.98 mm

1540

838

0.41

Glass, 6.88 mm

540

282

0.93

Glass, 6.88 mm

1540

838

0.47

Opaque

570

299

0.92

Opaque

1540

838

0.68

Red Lead

212

100

0.93

Rubber, Hard

74

23

0.94

Rubber, Soft, Gray

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

 

 

 

Surface

100

38

0.38

Black Loam

68

20

0.66

Plowed Field

68

20

0.38

Soot

 

 

 

Acetylene

75

24

0.97

Camphor

75

24

0.94

Candle

250

121

0.95

Coal

68

20

0.95

Stonework

100

38

0.67

Water

100

38

0.67

Waterglass

68

20

0.96

Wood

low

low

.80-.90

Beech Planed

158

70

0.94

Oak, Planed

100

38

0.91

Back to Knowledge Base