Hazet-Werk 1991-1 Mode D'emploi page 17

USA
Reminders
• Not recommended for use in measuring shiny
or polished metal surfaces ( stainless steel,
aluminium, etc.). See Emissivity.
• The unit cannot measure through transparent
surfaces such as glass. It will measure the
surface temperature of the glass instead.
• Steam, dust, smoke, etc., can prevent ac-
curate measurement by obstructing the unit's
optics.
Emissivity
• Emissivity is a term used to describe the
energy-emitting characteristics of materials.
• Most (90% of typical applications) organic
materials and painted or oxidized surfaces
have an emissivity of 0.95 (pre-set in the unit).
Inaccurate readings will result from measuring
shiny or polished metal surfaces. To compen-
sate, cove the surface to be measured with
masking tape or flat black paint. Allow time
for the tape to reach the same temperature
as the material underneath it. Measure the
temperature of the tape or painted surface.
(See EMS adjustment on pages 15 and 16)
Do not let the beam enter your eye, another person's eye or the eye of an animal!
Design and Function
3
This may cause severe eye injuries.
Emissivity Values
Substance
Asphalt
Cloth (black)
Concrete
Human skin
Cement
Leather
Sand
Charcoal (powder)
Earth
Lacquer
Water
Lacquer (matt)
Ice
Rubber (black)
Snow
Plastic
Glass
Timber
Ceramic
Paper
Marble
Chromium oxides
Plaster
Copper oxides
Mortar
Iron oxides
Brick
Textiles
GB
Thermal emissivity
0.90 to 0.98
0.98
0.94
0.98
0.96
0.75 to 0.80
0.90
0.96
0.92 to 0.96
0.80 to 0.95
0.92 to 0.96
0.97
0.96 to 0.98
0.94
0.83
0.85 to 0.95
0.90 to 0.95
0.90
0.90 to 0.94
0.70 to 0.94
0.94
0.81
0.80 to 0.90
0.78
0.89 to 0.91
0.78 to 0.82
0.93 to 0.96
0.90
17