– Align the height of the measuring tool (using a tripod or by under-
laying, if required) in such a manner that the center of the laser line
is projected exactly against the previously marked point II on wall B.
– Mark the center of the laser line as point III (vertically above or be-
low point I) on the wall A.
A
B
– The difference d of both marked points I and III on wall A indicates
the actual deviation of the measuring tool from the level plane.
The maximum permitted deviation dmax can be calculated as follows:
dmax = double the distance between the walls x 0.0118 in (0.3 mm)
Example: If the distance between the walls is 16 ft (5 m), the maxi-
mum deviation is dmax = 2 x 16 ft x 0.0118 in = 0.118 in (2 x 5m x
0.3 mm/m = 3mm). The marks must therefore be maximum 0.118 in
(3 mm) apart.
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