Meeting & Exceeding Standards: Atmospheric Conditions

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Under MIL-STD-801G atmospheric testing evaluates a device’s ability to withstand shock, radiation and acidity found in various conditions.

Low Pressure (Altitude)

Storage/Air Transport: For equipment transported or stored at high ground elevation or transported by air
Equipment is placed in a test chamber according to its storage or transport configuration. Air pressure within the test chamber is gradually adjusted to correspond with the expected transportation environment and maintained for a minimum of one hour.

Operation/Air Carriage: For equipment expected to operate at high ground elevation or within aircraft
Testing is the same as Storage/Air Transport except equipment is placed in the test chamber in its operational configuration.

Rapid Decompression: For equipment that could react dangerously and harm nearby personnel or the carrier (ground vehicle or aircraft) under a sudden decrease in pressure
Air pressure within the test chamber is set to the altitude of 2,438m (8,000ft), reduced within 15 seconds to air pressure at the altitude of 12,192m (40,000ft) and maintained for at least 10 minutes.

Explosive Decompression: For equipment exposed to instantaneous drops in pressure
Testing is the same as Rapid Decompression but altitudes are reduced within 0.1 seconds.

Explosives

Explosive Atmosphere: For equipment expected to operate in a fuel vapor environment without igniting the environment
The equipment is placed in the test chamber, and temperature and air pressure are raised to the highest level at which the equipment is expected to operate. A vapor of n-hexane fuel is introduced into the chamber and air pressure is gradually lowered to ground ambient. Operation of the equipment is tested within 1000 m of ground ambient pressure and continued until reaching ground ambient.

Explosive Containment: For hazardous equipment expected to contain an internal explosion or flame due to malfunction
The equipment is placed in the test chamber. Water vapor is set with a dew point lower than 10°C (50°F), and temperature and air pressure are raised to the highest level at which the equipment is expected to operate. The air pressure is reduced to 2000 m above ground ambient and n-hexane vapor is introduced into the chamber and interior of the equipment. Air pressure is further reduced to ground ambient and ignition is set off within the equipment.

Acidic Atmosphere

Equipment is placed in the test chamber and the temperature is adjusted to 35°C. After two hours an acidic solution with a pH of 4.17 is sprayed onto the equipment. For infrequent exposure or lower acidity, three cycles of spraying for two hours and storing for 22 hours are completed. For long exposure or highly acidic environments, four cycles of spraying for two hours and storing for seven days are completed.

Solar Radiation

Cycling State: For equipment operated minimally outside in hot climates
The equipment is placed in the test chamber and exposed to at least three 24-hour cycles of simulated solar radiation according to the expected environment. Within each cycle, the highest peak temperature is held for one hour.

Steady State: For equipment exposed to sunshine for long periods
Steady state testing is similar to Cycling but includes a four-hour dark period to simulate thermal stress. Ten cycles are completed for equipment occasionally deployed outside and 56 cycles for continuous outside deployment.

Sealevel Environmental Testing

Sealevel performs rigorous in-house testing and is experienced in creating rugged technology for operation in hazardous atmospheric conditions.