8.8.1 Waiver
The test shall be waived if the manufacturer has declared that the EUT cannot by design generate noise which could interfere with communication or audible alarms.
8.8.2 Objective
To check that acoustic noise generated by the EUT does not interfere with communication or audible warnings.
8.8.3 Method of measurement
The EUT or parts thereof, intended for installation in wheelhouses, shall be examined for acoustic noise by means of a sound-level meter complying with IEC 651. The EUT shall be set to the operating condition that gives rise to the highest level of unwanted acoustic noise power.
8.8.4 Result required
The acoustic noise power detected shall not exceed a peak level of 60 dB(A) at a distance of 1 m from any part of the EUT.
8.9 Compass safe distance
According to IEC 60945 11.2
8.9.1 Objective
To determine the distances above which the EUT shall not cause an unacceptable deviation of the ship's standard and steering compasses.
8.9.2 Method of measurement
The compass safe distances shall be determined in accordance with the method below, which is a revision in modern measurement units of the method described in ISO R.694.
Each unit of the EUT shall be tested in the position and attitude relative to the compass or magnetometer at which the error produced at the compass would be a maximum, provided the item can be fitted in this way.
The compass safe distance of any unit of the EUT is defined as the distance between the nearest point of the item and the centre of the compass and magnetometer at which it will not produce a deviation in the standard compass of more than 5.4°/H where H is the horizontal flux density in μT (microTesla), and 1 μT is equivalent to 0.01 Oe (Oersted).
For the steering compass, the standby steering compass and the emergency compass, the permitted deviation is 18°/H, H being defined as above.
Each uhit of the EUT shall be tested:
a) in the magnetic condition in which it is received;
b) after magnetisation in a d.c. field of 103/4π A/m, with a superimposed stabilising field of 18 × 103/4π A/m r.m.s. at 50 Hz (1 A/m = 4π 10-3Oe). If, however, damage to the EUT might result, the stabilising field should be omitted. The direction of the field is that in which, as estimated by inspection or from drawings, the resultant magnetisation will be greatest (for example the long axis of a ferromagnetic box):
c) in the energised condition, if the unit is capable of being energised electrically.
In each of the above tests the unit shall be rotated to determine the direction in which it produces the maximum deviation.
