3.5.1 The readings obtained may be affected if
the water depth is less than five times the draught or if there are
large reflecting surfaces in the ship's vicinity. Such conditions
shall therefore be noted in the noise survey report.
3.5.2 The meteorological conditions such as wind
and rain, as well as sea state, should be such that they do not influence
the measurements. Wind force 4 and 1 m wave height should not be exceeded.
If this cannot be achieved, the actual conditions shall be reported.
3.5.3 Care shall be taken to see that noise from
extraneous sound sources, such as people, entertainment, construction
and repair work, does not influence the noise level on board the ship
at the positions of measurement. If necessary, measured values may
be corrected for steady state background noise according to the energy
summation principle.