Sand and Dust MIL-STD-810, Method 510 testing is used to evaluate equipment’s ability to withstand exposure to blowing sand and dust. This test is to be performed in environmental chambers and replicates natural exposures expected in hot-dry regions of the world.
The standard defines dust as particles with a diameter less than 150 μm. Sand is defined as particles with a diameter between 150 to 850 μm. The standard further defines the prescribed composition of these particles to be used in the procedures.
Effects of Exposure to Sand and Dust
Sand and Dust can cause numerous effects on equipment that can result in serious degradation of performance or complete failure. Abrasion, erosion, and penetration of seals can occur. Effects caused by the interference of moving parts as particles enter into crevices, bearings, and joints can render equipment ineffective or hinder use. Additionally, when particles obstruct openings and vents, they can cause overheating.
Recent Revisions to This Test Method
The Sand and Dust test method was completely rewritten in Revision H, which was released in 2019. Changes were made to ensure that a more realistic distribution of particles in test chambers during a test. These changes led to the redesign of chambers in many test facilities and resulted in dust chambers being reduced in size. It is therefore important to make certain that chambers are available if you are testing larger equipment.
Revisions in MIL-STD-810 usually occur to create more realistic test environments using the latest available technology. In most cases there are few reasons to test to older revisions of the standard. This would especially be the case for this particular method.
Test Procedures for Method 510
There are two procedures in Method 510, Procedure I – Blowing Dust, and Procedure II – Blowing Sand:
Procedure I – Blowing Dust
Blowing Dust is conducted using specific air velocities. When measured data is not available the following representative values are to be used: An air velocity of 300 ±200 ft/min (1.5 ±1 m/s) is to be used to maintain test temperature conditions, and an air velocity of 1750 ±250 ft/min (8.9 ±1.3 m/s) is to be used to replicate desert winds. Typically, these wind speeds are to be uniformly across the area of the test item.
Temperatures should reflect the intended environments expected to be encountered in the equipment’s life cycle. Normally, this would include Hot Dry (A1) temperatures that would be found in the deserts of Asia, Africa, Australia, and North America. For ambient exposures, this would be 120 °F (49 °C), although higher temperatures can be employed to account for solar loading on equipment.
As moisture in the test chamber can result in caking of the dust, it is important to control the levels of relative humidity (RH). For the blowing dust procedure, the RH should not exceed 30 percent.
As previously mentioned, dust composition is specified in the standard. Normally, red China clay or silica flour is used, unless otherwise specified. Testing should be conducted for at least 6 hours at ambient temperature and 6 hours at the specified high temperature.
The test item may be rotated during testing to ensure that all faces have equal exposure. If necessary, operational tests should be conducted. These should be performed for at least 10-minute durations.
Procedure II – Blowing Sand
Blowing Sand should, unless otherwise specified, use the same temperatures as used in Blowing Dust. Generally, a wind velocity of 40 mph (18 m/s) or higher is used for testing. As the sand used in testing should have an angular composition, the reuse of sand from previous tests is not allowed, as the impact of particles will result in increased roundness of sand particles.
This test should be performed for a minimum of 90 minutes per side of equipment normally vulnerable to exposure. Required operational testing should be considered when writing a test plan.
Special Considerations for Sand and Dust Testing
Sand and Dust MIL-STD-810 Method 510 testing causes abrasion and will produce a coating of dust on test items. This could influence the results of testing performed after this method for Humidity, Solar Radiation, Fungus, Salt Fog/Corrosive Environments, and Acidic Environments. Care should be taken when developing the Test and Evalution Master Plan.
Inhalation of particles of dust and sand pose significant health hazards. Silica flour which is composed of ground quartz can cause silicosis. Appropriate personal protective equipment should be utilized to prevent exposure.
High levels of electrostatic electricity can buildup due to the combination of dry air with moving particles. It is important to consider adequate grounding schemes to prevent discharges that could damage the test unit.
Detailed Environmental Test Plan Templates
CVG Strategy offers EZ-Test Plan Templates for MIL-STD environmental (climatic/dynamic) and EMI/EMC testing documentation. Our Detailed Environmental Test Plans (DETP)s are written as specified in MIL-STD-810 Task 405. They are available for specific applications such as Ground Mobile, Ground Stationary, and Shipboard Controlled, Shipboard Uncontrolled, and Aircraft Military.
These DETPs include appropriate test methods, (such as Sand and Dust MIL-STD-810 Method 510) addendums for product specific information, test labels for photo identification and data sheets for collection of required data. Profile (LCEP).
Our Electromagnetic Interference Test Plans are written as specified by the Department of Defense. They contain the test methodology, addendums for product specific information, test labels for photo identification and data sheets. These plans are available for procedures listed in MIL-STD-461 and are also available for MIL-STD-1275, MIL-STD-704, and MIL-STD-1399-300.
Custom Test Plans are also available for applications not covered in the EZ-Test Plan offerings. These plans can be written for any number of applications and their relevant standards.
Put CVG Strategy’s Experience to Work for You
Companies of all sizes, from start up to established product developers, face challenges in product test and evaluation. This can particularly be the case when a product is developed for a new market sector or expanding sales internationally.
Properly tested products prevent costly product recalls, product redesign, and product liability. They maintain customer satisfaction and keep your company’s reputation in good standing. Contact CVG Strategy to see how our testing services can assist your engineering team with Sand and Dust MIL-STD-810 Method 510, or any other test and evaluation concern.