8 August 1973
3. 3.2.8 Dust. With the window cover closed, the range-
finder shall show no damage or deterioration after exposure to the dry
dust (fine sand) laden atmosphere specified in Method 510 of MIL-STD-810.
After exposure, the rangefinder shall meet the requirements of 3.3. 1.3
18.104.22.168 Salt fog~ The
range finder shall show no damage or
deterioration after exposure to the
salt fog atmosphere specified in
Method 509 of MIL-STD-81O. After
exposure, the rangefinder shall
meet the requirements of 3. 3.1.3
22.214.171.124 Fungus. The range finale r shall show no damage
or deterioration l fter exposure to an atmosphere containing a mixed
spore suspension conducive to fungus growth as specified in Method 508
of MIL-STD-81O. After exposure, the range finder shall meet the require-
ments of 3.3.1-3 and 126.96.36.199.
3.3.3 Electromagnetic compatibility. The range finder shall
comply with the electromagnetic compatibility emission limits specified in MIL-STD-
461 for Class XC equipment, except that the limits indicated by figures
2 through 8 herein shall apply.
3.3.4 Special operating conditions. The rangefinder, with
the protective covers closed, shall withstand without damage, water
hosing normally utilized to ciean grime from combat vehicles.
3.3.5 Inerchageability. The rangefinder shall meet all
the requirements of this specification without need for selective assembly
of the units listed in table I. The units shall be interchangeable such
that replacement of any single item or random combination of items of
the range finder permits the range finder to operate and perform to the
requirements of this specification.
3.3.6 Reliability. The rangefinder shall exhibit a mean
ranging between failure (MRBF) of 5000 rangings at a 90 percent confi-
3.317 Sealing. With the range finale r initially pressurized
with nitrogen or air to 5.0 l 1.0 pounds per square inch, gage (psig),
the Loss of pressure shall not exceed O. 22 psig in 2 hours.