MIL-STD-810 F/G Standards - Hermon Labs

EMC 

MIL-STD-810 F/G Standards 

Radio 

Telecom 

Environmental 

Product Safety 

Presented by Mr. Vladimir Kogan, Group Manager Environmental 

and Michael Mirin, Environmental Test Engineer. 

28-June-11 

International Approvals

jpg. Files

Seminar AGENDA 

• MIL-STD-810 introduction 09:00 – 09:30, Vladimir Kogan 

• MIL 810 overview – What it is 

• MIL 810 tests :Mechanical, Climatic, Special 

• MIL 810 F vs. MIL 810G 

• Explosive Atmosphere 09:30 – 10:30, Vladimir Kogan 

• Scope, Purpose and Test Process 

• Break 10:30 – 10:45 

• Mechanical testing 10:45-11:30, Michael Mirin 

Scope, Purpose and Test Process 

• Altitude and Decompression test , 11:30 – 12:50, Vladimir Kogan 

Low, High Temperatures and Humidity testing 

Scope, Purpose and Test Process 

• Lunch break, 13:00-14:00 

• Explosive & Mechanical presentation/demonstration 14:00 -15:00 

• Explosive & Mechanical presentation/demonstration 15:00 -16:00 

• Q & A 16:00

MIL-STD-810 F/G Standards Seminar 

WELCOME!

MIL-STD-810 F/G Introduction

MIL-STD-810 F/G Introduction 

Scope of the standard 

This standard contains materiel acquisition program planning and engineering direction 

for considering the influences that environmental stresses have on materiel throughout all 

phases of its service life. It is important to note that this document does not impose 

design or test specifications. 

“MIL-STD-810G, DEPARTMENT OF DEFENSE TEST METHOD STANDARD: 

ENVIRONMENTAL ENGINEERING CONSIDERATIONS AND LABORATORY TESTS 

(31 OCT 2008) – USA”


Broad range of environmental conditions that include: 

• Low pressure for ALTITUDE testing; 

• Exposure to HIGH AND LOW TEMPERATURES plus TEMPERATURE SHOCK (both operating 

and in storage); 

• RAIN (including wind blown and freezing rain); 

• HUMIDITY, 

• FUNGUS, 

• SALT FOG for rust testing; 

• SAND AND DUST exposure; 

• EXPLOSIVE ATMOSPHERE; 

• LEAKAGE; 

• ACCELERATION; 

• SHOCK and transport shock (i.E., Triangle/sine/square wave shocks); 

• GUNFIRE VIBRATION; 

• RANDOM VIBRATION.


History and rationale


This standard is approved for use by all Departments and Agencies of the Department of 

Defense (DoD). Although prepared specifically for DoD applications, this standard 

may be tailored for commercial applications as well. 

• MIL 810G includes significant changes vs. 810F 

• One new additional Part 

• 5 New Test Methods


The MIL- STD includes 3 parts


Part 3: 

WORLD CLIMATIC 

REGIONS – 

GUIDANCE 

Part 2: 

LABORATORY TEST 

METHODS 

Part 1: 

ENVIRONMENTAL 

ENGINEERING 

PROGRAM 

GUIDELINES 

Describes management, 

engineering, and technical 

roles in the environmental 

design and test tailoring 

process. 

It focuses on the process of 

tailoring materiel design and 

test criteria to the specific 

environmental conditions a 

materiel item is likely to 

encounter during its service 

life


Part One Environmental engineering program guide 

Task 401 - Environmental Engineering 

Management Plan (EEMP) 

Task 402 - Life Cycle Environmental Profile 

(LCEP) 

Task 403 - Operational Environment 

Documentation (OED) 

Task 404 - Environmental Issues/Criteria List 

(EICL) 

Task 405 - Detailed Environmental Test Plans 

(DETP) 

Task 406 - Environmental Test Reports (ETR)

MIL-STD-810 F/G Introduction: Roles

MIL-STD-810 F/G Life Cycle (Transportation)

MIL-STD-810 F/G Life Cycle (Operational)


Part 3: 


REGIONS – 

GUIDANCE 

Part 2: 

Part 1: 

ENVIRONMENTAL 

ENGINEERING 

PROGRAM 

GUIDELINES 

Contains environmental 

laboratory test methods to 

be applied according to the 

general and specific test 

tailoring guidelines 

described in Part One. 


METHODS

MIL-STD-810; 1962 

Test methods 

The MIL-STD-810 test series contains environmental laboratory test methods that are applied using specific test tailoring 

guidelines described within the standard.

MIL-STD-810 F/G : Part two Test methods “F”

MIL-STD-810 F/G: Part two Test methods “G”

MIL-STD-810 F/G: Part two Test methods comparison: 1962 vs. “G”


Contains a compendium of climatic 

data and guidance assembled from 

several sources. 

Part 3: 


REGIONS – 

GUIDANCE 

Part 1: 

ENVIRONMENTAL 

ENGINEERING 

PROGRAM 

GUIDELINES 

Part Three provides planning guidance 

for realistic consideration of climatic 

conditions in the research, 

development, test, and evaluation 

(RDTE) of materiel and materials used 

throughout their life cycles in various 

climatic regions throughout the world. 

Part 2: 


METHODS 

It is intended that this and related 

documents will help achieve the 

objective of developing materiel that will 

perform adequately under the 

environmental conditions likely to be 

found throughout its life cycle in the 

areas of intended use.

MIL-STD-810 F/G: Part three 

Areas of occurrence of climatic design types.


Distribution of absolute minimum temperatures


Distribution of absolute maximum temperatures

Explosive Atmosphere

Explosive Atmosphere 

Explosive Atmosphere test: Purpose 

The explosive atmosphere test is performed to: 

1. Demonstrate the ability of materiel to operate in fuel-air explosive atmospheres 

without causing ignition 

2. Demonstrate that an explosive or burning reaction occurring within encased 

materiel will be contained, and will not propagate outside the test item.

Explosive Atmosphere 

Application 

This method applies to all materiel designed for use in the vicinity of 

fuel-air explosive atmospheres associated with aircraft, automotive, 

and marine fuels at or above sea level.

Explosive Atmosphere: Limitations 

1. Conservative test 

If the test item does not ignite the test fuel-air mixture, there is a low probability that the 

materiel will ignite prevailing fuel vapor mixtures in service. Conversely, the ignition of the 

test fuel-air mixture by the test item does not mean the materiel will always ignite fuel vapors 

that occur in actual use. 

2. Altitudes above 16 km 

These procedures are not appropriate for test altitudes above approximately 16 km where 

the lack of oxygen inhibits ignition. 

3. High surface temperatures. 

This method is not intended to demonstrate ignition due to high surface temperatures.

Explosive Atmosphere: Effects 

Effects of explosive atmosphere environments 

Low levels of electrical energy discharge or electrical arcing by devices as simple as 

pocket transistor radios can ignite mixtures of fuel vapor and air. 

Fuel vapors in confined spaces can be ignited by a low energy discharge such as a 

spark from a short-circuited flashlight cell, switch contacts, electrostatic discharge, 

etc.

Explosive Atmosphere: Sequence 

Sequence among other methods 

Considering the approach to conserve test item life by applying what are perceived to 

be the least damaging environments first, generally apply the explosive atmosphere 

test late in the test sequence. 

Vibration, shock, and temperature stresses may distort seals and reduce their 

effectiveness, thus making ignition of flammable atmospheres more likely. 

Recommend the test item first undergo the above tests (on the same item) to better 

approximate the actual operational environment.

Explosive Atmosphere: Procedure Variations 

Selecting Procedure Variations. 

Before conducting this test, complete the tailoring process by selecting specific 

procedure variations (special test conditions/techniques for this procedure) based on 

requirements documents, Life Cycle Environmental Profile (LCEP), and information 

provided with these procedures. 

Fuel 

Unless otherwise specified, use n-hexane as the test fuel, either reagent grade or 95 percent n- 

hexane with 5 percent other hexane isomers. This fuel is used because its ignition properties in 

flammable atmospheres are equal to or more sensitive than the similar properties of 100/130- 

octane aviation gasoline, JP-4 and JP-8 jet engine fuel. Optimum mixtures of n-hexane and air will 

ignite from temperatures as low as 223°C, while optimum JP-4 fuel-air mixtures require a minimum 

temperature of 230°C for auto-ignition, and 100/130 octane aviation gasoline and air requires 

441°C for hot-spot ignition. Minimum spark energy inputs for ignition of optimum fuel vapor and air 

mixtures are essentially the same for n-hexane and for 100/130-octane aviation gasoline. Much 

higher spark energy input is required to ignite JP-4 or JP-8 fuel-air mixtures. Use of fuels other 

than n-hexane is not recommended.


Temperature 

Heat the fuel-air mixture to the highest ambient air temperature at which the materiel is 

required to operate during deployment and provide the greatest probability of ignition. 

Altitude simulation 

The energy required to ignite a fuel-air mixture increases as pressure decreases. Ignition energy 

does not drop significantly for test altitudes below sea level. Therefore, unless otherwise 

specified, perform all tests with at least two explosive atmosphere steps, one at the 

highest anticipated operating altitude of the materiel (not to exceed 12,200 m (40,000 ft.) where 

the possibility of an explosion begins to dissipate), and one between 78 and 107 kPa which is 

representative of most ground ambient pressures. 

Because of the lack of oxygen at approximately 16 km, do not perform this test at or above this 

altitude.


Fuel-vapor mixture 

Use a homogeneous fuel-air mixture in the correct fuel-air ratios for the explosive atmosphere test. 

Fuel weight calculated to total 3.8 percent by volume of the test atmosphere represents 1.8 

stoichiometric equivalents of n-hexane in air, giving a mixture needing only minimum energy for ignition. 

Required information to determine fuel weight: 

Chamber air temperature during the test. 

Fuel temperature. 

Specific gravity of n-hexane 

Test altitude: ambient ground or as otherwise identified. 

Net volume of the test chamber (L)

Explosive Atmosphere Fuel Calculation 

Calculation of the volume of liquid n-hexane fuel for each test altitude:

Explosive Atmosphere: Test Facility 

Explosive atmosphere set up data sheet 

Chamber volume 

160 L 

Chamber dimension 

Ø 45 cm, depth 70 cm 

Chamber temperature 

ambient to +80°C 

Chamber altitude 

up to 20 km (65.617 ft) (55 mBar)

Explosive Atmosphere: Test procedure 

Preparation for test 

Before starting the test, review pretest information in the test plan to determine test details: 

procedures, test item configuration, test temperature and test altitude. 

Install the test item in the test chamber in such a manner that it may be operated and controlled 

from the exterior of the chamber via sealed cable ports. 

Unless permanently sealed (not to be opened for maintenance or other purposes), remove or 

loosen the external covers of the test item to facilitate the penetration of the explosive mixture. Test 

items requiring connection between two or more units may, because of size limitations, have to be 

tested independently. In this case, extend any interconnections through the cable ports. 

Operate the test item to determine correct operation. 

In all instances, operate the test item in a manner representative of service use.


Operation in explosive atmosphere 

Step 1. With the test item installed, seal the chamber and stabilize the test item and chamber inner walls 

to within 10°C below the high operating temperature of the test item. 

Step 2. Adjust the chamber air pressure to simulate the highest operating altitude of the test item (not to 

exceed12,200m) plus 2000 meters to allow for introducing, vaporizing, and mixing the fuel with the air. 

Step 3. Slowly introduce the required volume of n-hexane into the test chamber. 

Step 4. Circulate the test atmosphere and continue to reduce the simulated chamber altitude for at least 

three minutes to allow for complete vaporization of fuel and the development of a homogeneous mixture. 

Step 5. At a pressure equivalent to 1000m above the test altitude, verify the potential explosiveness of 

the fuelair vapor by attempting to ignite a sample of the mixture taken from the test chamber using a 

spark-gap device with sufficient energy to ignite a 3.82-percent hexane mixture. If ignition does not occur, purge the 

chamber of the fuel vapor and repeat Steps 1-4.


Operation in explosive atmosphere 

Step 6. Operate the test item and continue operation from this step until completion of Step 7. Make and 

break electrical contacts as frequently and reasonably possible. 

Step 7. To ensure adequate mixing of the fuel and air, slowly decrease the simulated chamber altitude at 

a rate no faster than 100 meters per minute by bleeding air into the chamber. 

Step 8. Stop decreasing the altitude at 1000m below the test altitude, perform one last operational check 

and switch off power to the test item. 

Step 9. Verify the potential explosiveness of the air-vapor mixture as in Step 5 above. If ignition does not 

occur, purge the chamber of the fuel vapor, and repeat the test from Step 1. 

Step 10. Adjust the simulated chamber altitude to the equivalent of 2000 m above site pressure. 

Step 11. Repeat Steps 3-7. At site pressure, perform one last operational check and switch-off power to 

the test item. 

Step 12. Verify the potential explosiveness of the air-vapor mixture as in Step 5, above. If ignition does not 

occur, purge the chamber of the fuel vapor, and repeat the test from Step 10. 

Step 13. Document the test results.


Operation in Explosive Atmosphere 

0 Test Altitude

Explosive Atmosphere test algorithm (only MIL-STD-810 F/G)

Explosive Atmosphere: test results example 

Temperature and pressure at test altitudes 30kft to site level 

Explosion tests 

in the sampling tube

Mechanical tests

Mechanical tests: Vibration 

What is vibration: 

According to WWW Webster on-line, as of 1997, Main Entry: 

vi·bra·tion 

Pronunciation: vI-’brA-sh&n. Function: noun. 

Date: 1655 

1. a periodic motion of the particles of an elastic body or medium in alternately opposite directions from 

the position of equilibrium when that equilibrium has been disturbed (as when a stretched cord produces 

musical tones or particles of air transmit sounds to the ear) 

b : the action of vibrating : the state of being vibrated or in vibratory motion: as 

(1) : OSCILLATION (2) : a quivering or trembling motion : QUIVER 

2. an instance of vibration 

3. vacillation in opinion or action : WAVERING 

4. a characteristic emanation, aura, or spirit that infuses or vitalizes someone or something and that can 

be instinctively sensed or experienced, often used in plural. 

b : a distinctive, usually emotional atmosphere capable of being sensed, usually used in plural 

- vi·bra ·tion ·al /-shn&l, -sh& -n&l / adjective 

vi·bra·tion·less /-sh&n-l&s/ adjective

Mechanical tests: Vibration 

Purpose of Vibration: 

Vibration tests are performed to: 

1. Develop materiel to function in and withstand the vibration exposures of a life cycle including 

synergistic effects of other environmental factors, materiel duty cycle, and maintenance. 

2. Verify that materiel will function in and withstand the vibration exposures of a life cycle. 

Consumers expect and demand products of high quality and reliability. To fulfill these requirements we 

must consider vibration, since at some time in its life the product will be subjected to vibration. Poor 

mechanical design will result in mechanical failure and customer dissatisfaction which will add cost and 

reduce credibility.

Mechanical tests: Vibration

Mechanical tests: Reasons for Vibration Testing 

Some reasons for Vibration Testing 

- Reduce product development time 

- Ensure new products are fit for purpose 

- Reduce in-plant rework due to QA rejection 

- Reduce damage in transit and subsequent rejection by the customer 

- Reduce marginal or non-performance rejection under Warranty 

- Reduce legal costs and damage claims due to incorrect operation of the product 

- Maintain a good reputation for the company and its products 

- Maintain profit margins 

In a highly competitive world marketplace Vibration Testing makes good sense.

Mechanical tests: Sequence among other methods 

The accumulated effects of vibration-induced stress may affect materiel performance under other 

environmental conditions such as temperature, altitude, humidity, leakage, or electromagnetic 

interference (EMI/EMC). When evaluating the cumulative environmental effects of vibration and other 

environments, expose a single test item to all environmental conditions, with vibration testing 

generally performed first. 

If another environment (e.g., temperature cycling) is projected to produce damage that would make the 

materiel more susceptible to vibration, perform tests for that environment before vibration tests. For 

example, thermal cycles might initiate a fatigue crack that would grow under vibration.

Mechanical tests: Vibration Effects 

Effects of vibration environment 

Vibration results in dynamic deflections of and within materiel. These dynamic deflections and associated 

velocities and accelerations may cause or contribute to structural fatigue and mechanical wear of 

structures, assemblies, and parts. In addition, dynamic deflections may result in impacting of elements 

and/or disruption of function. Some typical symptoms of vibration-induced problems follow. 

1. Chafed wiring. 

2. Loose fasteners/components. 

3. Intermittent electrical contacts. 

4. Electrical shorts. 

5. Deformed seals. 

6. Failed components. 

7. Optical or mechanical misalignment. 

8. Cracked and/or broken structures. 

9. Migration of particles and failed components. 

10. Particles and failed components lodged in circuitry or mechanisms. 

11. Excessive electrical noise. 

12. Fretting corrosion in bearings.

Mechanical tests: Vibration environment categories

Mechanical tests: Type of Vibration - Sine 

Sine Vibration 

One of the most common vibration tests is a swept sine test. These tests, as they imply, are a test where 

the signal driven into the vibrator is a sine wave and the frequency of the sine wave will change with time 

i.e. it will sweep. The level or amplitude of the signal measured on the vibration table can be either 

Acceleration, Velocity or Displacement. However, the sensor measuring the vibration is normally an 

Accelerometer which produces an output proportional to Acceleration. The controller, however, can 

convert the signal from the accelerometer to Velocity (by integration) or Displacement (by double 

integration).


The units used for sinusoidal vibration testing are: 

Frequency Hz or radians/second 

Displacement mm or inches peak - peak or peak 

Velocity m/s or in/sec peak 

Acceleration m/s² or gn peak 

Metric Units Imperial Units SI Units 

D = mm peak - peak D = in peak - peak D = mm peak - peak 

V = mm/s peak V = in/s peak V = mm/s peak 

A = gn peak A = gn peak A = m/s² peak 

F = Hz F = Hz F = Hz 

G = 9806.65 mm/s² G = 386.0885827 in/s² G = 1000 mm/s² 

= 3.141592654 = 3.141592654 = 3.141592654


There must be hundreds, if not thousands, of swept sine test specifications, but whatever the test, it 

should define the following: 

1. The upper and lower frequency of the test, 

2. The level to be maintained at the appropriate frequency, 

3. The rate at which the frequency will sweep and whether it is logarithmic or linear. 

4. The duration of the test or the number of sweeps. 

In addition to the option that we have discussed (Sweep Sine), in which sine runs at certain velocity 

(sweep rate), there is also an option, where sine will “stand” a certain time in one frequency. This 

vibration is called Sine Dwell. 

There is also possibility to combine several frequencies in a single experiment, each frequency will be a 

certain time. 

Because sweep sine "running" at certain frequencies and any moment he is located at certain frequency, 

main use is for research - testing the product behavior, search for resonance frequencies (Resonance 

Search), and the goals like this. 

But there are also cases that sweep sine are used to complete an endurance and resistance tests of the 

product. 

As we said before, there is also sine dwell. He is used if we want to put load on certain frequencies, 

which were found problematic or suspected as those.

Mechanical tests: Type of Vibration - Random 

If we observe a structure which has several beams of different length and we excite the structure with a 

swept sine test, each beam will vibrate vigorously when excited by its unique resonant frequency. 

However, if we excite the same structure with a broad band random signal, we will observe that all the 

beams are vibrating vigorously which would tend to indicate that all of the frequencies are present at the 

same time. Well they are, and they aren’t. This may seem irrational. However if you consider that over a 

short period of time that several frequencies are present, but the quantity and phase of those frequencies 

is varying randomly it may make more sense. Time is the key to understanding random. In theory, you 

must consider an infinite period of time in order to produce a true spectrum analysis of a random signal. 

If the signal is truly random, it will never repeat. 

The equipment used to analyze random signals years ago employed electronic bandpass filters to 

separate and quantify each frequency. All modern spectrum analyzers now use a mathematical process 

known as an FFT (Fast Fourier Transform).

Mechanical tests: Random 

As a further explanation of random the following may help. The diagram below shows how sine waves of 

different frequencies can be summed to form a complex waveform. 

10Hz 

20Hz 

50Hz 

90Hz 

Sum 

0.1 sec

Mechanical tests: Random


Mechanical tests: Random 

Figure and Break points for curves Composite two-wheeled trailer vibration exposure.


Mechanical tests: Shock 

In field simulation tests were examined three general types of mechanical motion and force: 

1. Continuous and periodic (like sine vibration) 

2. Continuous, but not periodic (like random vibration) 

and the last type 

3. Not continuous and not periodic 

The nearest thing for this is a mechanical shock.


A mechanical or physical shock is a sudden acceleration or deceleration caused, for 

example, by impact, drop, kick, earthquake, or explosion. Shock is a transient physical 

excitation. 

Purpose of Shock test: 

Shock tests are performed to: 

1. provide a degree of confidence that materiel can physically and functionally withstand the relatively 

infrequent, non-repetitive shocks encountered in handling, transportation, and service environments. This 

may include an assessment of the overall materiel system integrity for safety purposes in any one or all of 

the handling, transportation, and service environments; 

2. determine the materiel's fragility level, in order that packaging may be designed to protect the 

materiel's physical and functional integrity; and 

3. test the strength of devices that attach materiel to platforms that can crash.


Effects of shock. 

Mechanical shock has the potential for producing adverse effects on the physical and functional integrity 

of all materiel. In general, the level is affected by both the magnitude and the duration of the shock 

environment. Durations of shock that correspond with natural frequency periods of the materiel and/or 

periods of major frequency components in input shock environment waveforms that correspond with 

natural frequency periods of the materiel will magnify the adverse effects on the materiel's overall 

physical and functional integrity.


Sequence among other methods. 

Sequencing among other methods will depend upon the type of testing, i.e., developmental, qualification, 

endurance, etc., and the general availability of test items for test. Normally, schedule shock tests early in 

the test sequence, but after any vibration tests. 

(1) If the shock environment is deemed particularly severe, and the chances of materiel survival without 

major structural or operational failure are small, the shock test should be first in the test sequence. This 

provides the opportunity to redesign the materiel to meet the shock requirement before testing to the 

more benign environments. 

(2) If the shock environment is deemed severe, but the chance of the materiel survival without structural 

or functional failure is good, perform the shock test after vibration and thermal tests, allowing the 

stressing of the test item prior to shock testing to uncover combined vibration, and temperature failures. 

(3) There are often advantages to applying shock tests before climatic tests, provided this sequence 

represents realistic service conditions. Test experience has shown that climate-sensitive defects often 

show up more clearly after the application of shock environments. 

However, internal or external thermal stresses may permanently weaken materiel resistance to vibration 

and shock that may go undetected if shock tests are applied before climatic tests.

Mechanical tests: Shock types 

Classical shock pulses (mechanical shock machine). Unless the procedure requires the use of a 

classical shock pulse, the use of such a pulse is not acceptable unless it can be demonstrated that 

measured data is within the tolerances of the classical shock pulses. Only two classical shock pulses are 

defined for testing in the method – the terminal peak sawtooth pulse, and the trapezoidal pulse.

Mechanical tests: Shock types - sawtooth pulse

Mechanical tests: Shock types - trapezoidal pulse

Mechanical tests: Test facility - LDS V875 Shaker specification 

LDS V875 Electrodynamic Shaker 

System vibration force (kN) 35.6 

System max shock force (kN) 105 

Max acceleration sine peak (gn) 110 

System velocity sine peak (m/s) 1.8 

Displacement pk-pk (mm) 50.6 

Payload, max (kg) 600

Mechanical tests: Test facility – “Closed loop”

Mechanical tests: Test facility – Fixture requirements and design

MIL-STD-810 F/G Standards - Hermon Labs

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