Bosch GLM 15 Consignes D'utilisation/De Sécurité page 14

Influence Effects on the Measuring Result
Due to physical effects, faulty measurements cannot be excluded
when measuring on different surfaces. Included here are:
– Transparent surfaces (e.g., glass, water),
– Reflecting surfaces (e.g., polished metal, glass),
– Porous surfaces (e.g. insulation materials),
– Structured surfaces (e.g., roughcast, natural stone).
Also, air layers with varying temperatures or indirectly received
reflections can affect the measured value.
Accuracy Check of the Distance Measurement
The accuracy of the distance measurement can be checked as
follows:
– Select a permanent measuring section with a length of
approx. 3 ft to 33 ft (1 m to 10 m); its length must be precisely
known (e.g. the width of a room or a door opening). The
measuring distance must be indoors; the target surface for the
measurement must be smooth and reflect well.
– Measure the distance 10 times after another.
The deviation of the individual measurements from the mean value
must not exceed ±1/16" (1.6mm). Log the measurements, so that
you can compare their accuracy at a later point of time.
Cause
Temperature warning indicator (b) flashing; measurement
not possible
Measuring tool not within the
tool has operating temperature range
between +14°F and 104°F
( –10°C and +40°C)
Battery low indicator (a) appears
Battery voltage decreasing
(measurement still possible).
Battery low indicator (a) flashing; measurement not possible
Troubleshooting
-14-
Corrective Measure
Wait until the measuring
reached the operating
temperature
Replace batteries