5.1.3.1 Airborne noise. Equipment generated airborne noise shall be in
accordance with MIL-STD-740-1. Tests are specified in MIL-STD-740-1. Tailoring
guidance for the grade to be required is provided below:
Grade A3 -
Equipment is that which is to be installed in spaces
where direct speech
communication shall be understood with minimal error and without repetition over
a distance of 2m (6.5 feet) or less.
Grade A12 - Equipment is that which
is to be installed in spaces
where direct speech communication shall be
understood with minimal error and without repetition over a distance greater
than 2m (6.5 feet).
Grade B - Equipment is that which will be placed in
spaces where
comfort of personnel in their quarters is the principal
consideration.
Grade C - Equipment is that which will be placed in the
sonar room, sick bay, library, or other spaces requiring low sound levels and
which are not covered in other categories.
Grade D - Equipment is that
which will be placed in spaces where
avoidance of hearing loss is the prime
consideration and intelligible speech communication is not normally
required.
Grade E - Equipment is that which will be placed in high
sound
level areas where voice communication is
accomplished with high vocal effort and where amplified speech and telephones
are normally available.
5.1.3.2 Structureborne noise. Equipment
generated structureborne noise shall be in accordance with type III equipment
of MIL-STD-740-2. Tests are specified in MIL-STD-740-2.
5.1.3.3
Alternating current (ac) power. The equipment shall meet the operational
constraints (including, but not limited to, harmonic current content, ramp
loading, and so forth for type I power in accordance with MIL-STD-1399,
section 300 (see
5.1.1.1
).
5.1.3.4 Submarine direct current
(dc) power. The equipment shall meet the operational constraints in accordance
with MIL-STD-1399, section 390 (see 5.1.1.2).
