MIL-STD-810H Sand and Dust Testing, specifically known as MIL-STD-810H-510.7 or Test Method 510.7, is conducted to assess a system's resistance to dust and sand particles, which have the potential to obstruct openings and penetrate critical components such as cracks, crevices, bearings, and joints.
The standard categorizes dust as particulates less than 150 microns in diameter and sand as particulates ranging from 150 to 850 microns in diameter.
How MIL-STD-810 Sand and Dust Testing is Conducted:
Environmental MIL-STD-810 sand and dust testing involves placing a system in a blowing chamber, exposing it to controlled sand or dust particles while regulating temperature, relative humidity, air velocity, particle composition, particle concentration, and system orientation.
Potential Harmful Effects Include:
Surface Wear and Tear:
Abrasion and erosion of surfaces.
Penetration of seals.
Degradation of electrical circuits.
Blockage of Openings:
Obstruction or clogging of openings and filters.
Physical interference with mating parts.
Impairment of Moving Components:
Fouling or interference of moving parts.
Thermal Conductivity Reduction:
Reduction of thermal conductivity.
Optical Characteristics Distortion:
Interference with optical characteristics.
Overheating and Fire Hazard:
Overheating and fire hazard due to restricted ventilation or cooling.
Wear and increased fretting between mating surfaces.
Chaffing Between Contact Surfaces:
Increased chaffing between non-mating contact surfaces.
Weight gain and static or dynamic balance.
Signal Transmission Attenuation:
Attenuation of signal transmission.
Sand and Dust Testing Methods:
Procedure I – Blowing Dust:
Exposes the system to circulating dust particles for 12 hours.
Temperature conditions maintained at standard ambient air temperatures.
Relative humidity not exceeding 30 percent.
Air velocity adjusted to simulate intended environments.
Procedure II – Blowing Sand:
Exposes the system to quartz sand particles for 90-minute intervals.
Temperature conditions and air velocity adjusted to simulate real-world conditions.
System reoriented at intervals to maximize erosion effects.
Both procedures assess damage and impairment, ensuring the system's capability to operate during real-world sand and dust events. The standardization of particle size accommodates variations in sand composition across different global regions.