Salt Fog – MIL-STD-810

What Is Salt Fog — MIL-STD-810?

The salt fog test is a test in which the specimen is exposed for a specified duration to a fog atmosphere generated from a salt solution of defined concentration, evaluating corrosion formation and functional degradation.

Purpose of Salt Fog — MIL-STD-810

The purpose is to verify that equipment intended for marine and coastal environments retains its function and structural integrity in a salt-laden atmosphere.

Which Products Is Salt Fog — MIL-STD-810 Applied To?

Naval-platform equipment
Military vehicles and outdoor equipment
Coastal-facility electronics
Fasteners and enclosures

In Which Sectors Is Salt Fog — MIL-STD-810 Used?

DefenceAerospaceSpaceElectronics

Standards Related to Salt Fog — MIL-STD-810

MIL-STD-810environmental engineering assessments and laboratory tests test

Salt Fog — MIL-STD-810 Conditions

Solution: 5% NaCl for ASTM B117 and ISO 9227 NSS; pH 6.5–7.2
Temperature: Chamber temperature 35 °C ± 2 °C
Exposure: Wet and dry periods are applied alternately in MIL-STD-810 Method 509
Time: Defined in the specification; given as a number of cycles in equipment tests

Equipment for Salt Fog — MIL-STD-810

Salt-fog chamber
Solution-preparation and pH-measurement rig
Fog-collection funnels and flow-rate measurement
Function-monitoring equipment

Sample Requirements for Salt Fog — MIL-STD-810

The specimen must be in operating configuration
Specimen placement and angle are defined in the standard
Function and visual condition must be recorded before the test
Solution dripping from specimens must not touch another specimen

Duration of Salt Fog — MIL-STD-810

From 48 hours to several weeks, depending on the specification.

Salt Fog — MIL-STD-810 Procedure

1The solution is prepared and the chamber conditions are verified.
2The specimen is placed at the defined angle and position.
3Exposure is applied for the defined duration or number of cycles.
4The specimen is removed and rinsed per the standard.
5Corrosion and function are assessed.

Salt Fog — MIL-STD-810 Acceptance Criteria

The acceptance criterion is given in the specification: continuity of function and the absence of corrosion beyond the defined class.

Evaluation of Results

Salt-fog duration cannot be directly converted to service life; the test is a ranking and comparison tool. MIL-STD-810 Method 509 and ASTM B117 are not the same test: the military method includes wet/dry cycles and also evaluates equipment function.

Salt Fog — MIL-STD-810 Report

Standard and method applied
Solution concentration and pH
Chamber temperature and fog flow rate
Exposure duration or number of cycles
Corrosion grading and function results

Accreditation

EUROLAB holds internationally recognised accreditation obtained from accreditation bodies party to the IAF and ILAC multilateral recognition arrangements, under ISO/IEC 17025 for laboratory testing, ISO/IEC 17020 for inspection and surveillance, and ISO/IEC 17021-1 and ISO/IEC 17065 for system and product certification. This chain ensures the reports and certificates issued are accepted worldwide.

Whether this test can be offered within accredited scope depends on your product and the standard applied; since accreditation is method-based, the scope is confirmed in writing at the quotation stage.

Scope and authorisations

Related Regulations

Defence and naval-platform specifications

Savunma Testleri — What Does This Testing Field Cover?

The section below describes the field that the Salt Fog test belongs to; the conditions and acceptance criteria of this particular test are given in the sections above. The scope specific to your product is confirmed in writing at the quotation stage.

Defence testing shows that equipment keeps working in a military mission environment. What distinguishes it from civil testing is not only the severity of the levels; the ASSUMPTION ITSELF is different. The equipment must work on the first attempt, after months of storage, in an environment where maintenance is not available, inside a platform crowded with its own transmitters and receivers.

This assumption shapes the test plan. For a civil product "normal use" can be defined; for military equipment what is defined is the LIFE CYCLE ENVIRONMENTAL PROFILE: the exposure of every stage is listed — from manufacture to storage, from storage to shipment, to transport on a vehicle, to use in the field and to maintenance — and the testing is derived from that list.

On the environmental side, MIL-STD-810 methods are applied: temperature, humidity, altitude, rain, sand and dust, salt fog, fungus, shock, vibration, explosive atmosphere and gunfire vibration. The standard itself sets no acceptance criterion; which method is applied at which level, and what is acceptable, come from the programme specification.

On the electromagnetic side, MIL-STD-461 requirements come into play and interference within the platform is controlled. It measures the same physics as civil EMC but with a different assumption: the equipment will operate on a platform crowded with its own radars and radios, and interference inside the platform puts the mission directly at risk. The limits are therefore far stricter.

Power quality is a separate body of work. MIL-STD-1275 for military vehicles and MIL-STD-704 for aircraft define the supply characteristics: voltage ranges, transients, ripple and interruption behaviour. This is where commercially derived equipment most often gets stuck when integrated into a military platform.

On the shock side, naval vessels carry their own regime: the MIL-S-901 high-impact shock test simulates the effect of an underwater explosion and tests the equipment on a real impact machine. This is an entirely different scale from classical laboratory shock testing.

The suitability of commercial off-the-shelf (COTS) equipment for military use is a growing subject in the field. Cost and lead time pressures encourage the use of commercial products; but a commercial product is not considered suitable unless it has been through the military profile, and a gap analysis plus additional qualification is required.

In this family the test plan comes from the PROGRAMME SPECIFICATION. The phrase "complies with MIL-STD-810" is therefore not a verifiable claim on its own; which method, which procedure, which level and which revision must all be answered.

Method groups in this field

Environmental
MIL-STD-810 methods: temperature, humidity, altitude, solar radiation, rain, sand and dust, fungus, salt fog, immersion, explosive atmosphere.
Mechanical
Vibration (random, sine, gunfire), shock, acceleration, free fall and transport simulation.
Electromagnetic
MIL-STD-461 CE/CS/RE/RS requirements; MIL-STD-464 at platform level.
Power quality
Conformity to the MIL-STD-1275 vehicle and MIL-STD-704 aircraft supply characteristics.
High-impact shock
The MIL-S-901 naval shock test; simulation of the effect of an underwater explosion.
Component qualification
MIL-STD-883 microelectronics and MIL-STD-202 electronic parts test methods.

Commonly confused in this field

The phrase "MIL-STD-810 certified" is incorrect; the standard produces no certificate, the output is a qualification report.
A conformity claim that does not state the method, procedure and level cannot be verified.
The revision letter (F, G, H) changes the content of methods and the procedure numbers; the specification must state the revision.
A civil EMC report does not replace MIL-STD-461; the limits, distances and set-ups are different.
Power quality is the requirement most often skipped when integrating a commercial product into a military platform.
Applying a method does not show that the equipment maintains its function in that environment; the functional acceptance criterion is defined separately.

Which decisions these results support

Qualification under a supply contract
Component verification before platform integration
Suitability of commercially derived equipment for military use and gap analysis
Specification compliance in NATO and export programmes
Establishing the life cycle environmental profile

Related Tests

Frequently Asked Questions About Salt Fog — MIL-STD-810

How many years of field life does 240 hours of salt fog correspond to?

No such conversion can be made. The salt-fog test is accelerated and comparative; corrosion mechanisms in the field progress at different rates. The result is used only to rank alternatives tested in the same run.