MIL-PRF-22750: Epoxy Coating Standard for Military Equipment
MIL-PRF-22750 is a United States military performance specification covering two-component, high-solids epoxy coatings supplied as a kit. These coatings are applied to military equipment requiring long-term corrosion protection, chemical resistance, and durability under sustained environmental exposure.
The current edition is MIL-PRF-22750H, dated 29 July 2025. The U.S. Army Research Laboratory is the preparing activity and the Naval Air Systems Command (NAVAIR) the lead standardisation activity, and the specification is used across the U.S. Army, Navy, and Air Force, as well as allied defence industries and defence contractors worldwide.
What Is MIL-PRF-22750?
MIL-PRF-22750 defines the performance requirements that an epoxy coating must meet to be approved for use on military and government equipment. It is not a single product but a qualification framework. Coatings that pass the required testing are listed on the Qualified Products List (QPL-22750) maintained by the Department of Defense.
Only QPL-listed products can be specified in military contracts and government projects. Procurement teams should always verify that the specific MIL-PRF-22750 product they are using appears on the current QPL before application.
MIL-PRF-22750 coatings are two-component systems consisting of a pigmented epoxy resin base and a curing agent. When mixed and applied, they form a dense cross-linked film that resists chemicals, abrasion, and environmental degradation.
Most types are applied over a qualified primer to maximise adhesion and corrosion resistance. Revision G names MIL-DTL-53022 or MIL-DTL-53030 on pretreated steel and MIL-PRF-23377 or MIL-PRF-85582 on aviation systems. Type III is the exception: it is formulated for direct-to-metal application.
Earlier editions were issued as MIL-C-22750, a designation still found on older drawings and painting instructions. Revisions D (1980) and E (1989) carried that prefix before the document became a performance specification.
Key Performance Requirements
MIL-PRF-22750 coatings must meet specific mechanical, chemical, and environmental criteria. The table below summarises the most important performance requirements as set in revision G with Amendment 1 (30 April 2014). Confirm each value against revision H before writing it into a new contract.
| Property | Requirement |
|---|---|
| Adhesion | Dry tape adhesion 4B or better (ASTM D3359, method B); wet tape adhesion 4A or better after 24 hours of water immersion |
| Hardness | No fixed pencil hardness; after water or fuel exposure the film may soften by no more than two pencil grades (ASTM D3363) |
| Chemical resistance | Must resist lubricating oil to MIL-PRF-23699 (24 hours at 121 °C), hydraulic fluids to MIL-PRF-83282 and MIL-PRF-87257, JP-8 fuel (168 hours) and water (168 hours) |
| Corrosion protection | Type III (direct to metal): 1,000 hours of ASTM B117 salt spray and 40 cycles of GMW 14872 cyclic corrosion on steel and aluminium |
| Flexibility | Must withstand a 180-degree bend over a 1 inch mandrel without cracking or flaking (ASTM D522, method B) |
| Colour stability | Colour difference below 3.0 ΔE after 500 hours of accelerated weathering (ASTM G155, cycle 1), and 2.0 ΔE or less after 60 minutes at 121 °C |
| Drying time | Set to touch within 4 hours and dry hard within 8 hours |
| VOC limits | Maximum 340 g/L (2.8 lb/gal) as packaged; free of inorganic hazardous air pollutants, including lead and chromium compounds |
Types and Classes
MIL-PRF-22750 defines types, classes and grades to cover different application requirements and operational environments. In revision G with Amendment 1 the types are:
- Type I: the standard formulation, cancelled by Amendment 1 and directly replaced by Type II.
- Type II: a formulation free of volatile organic hazardous air pollutants (VOHAP), applied over a primer.
- Type III: a VOHAP-free direct-to-metal formulation, offered in semi-gloss and lusterless colours only.
- Type IV: a self-contained portable kit for brush, roller or cartridge application, holding a Type II or Type III coating.
Classes set the carrier: Class H is a high-solids, solvent-based coating and Class W a water-based one. Grades set the exposure. Grade A is for Navy and Army equipment that needs weather resistance and may also be used as Grade B, while Grade B is for the interior of tactical equipment only.
Colour is not a class. It is ordered by its FED-STD-595 colour number, which forms part of the part number, in gloss, semi-gloss or lusterless (flat) finishes. Flat finishes are typically specified for tactical applications to reduce glare and visual signature.
Coatings are applied by spray, including electrostatic spray, or by brush, roller or cartridge from Type IV kits, and cure at ambient temperature. Revision G air-dries its test panels for at least seven days before performance testing, a sign that full film properties take days rather than hours to develop.
MIL-PRF-22750 Touch Up and Repair
Touch up of MIL-PRF-22750 coated surfaces follows the same material requirements as the original application. The touch up area must be properly prepared, including cleaning and light abrasion of the surrounding coating to ensure adhesion at the repair boundary.
For field touch up, Type IV self-contained portable kits for brush, roller or cartridge application are available from QPL-listed manufacturers. They hold a Type II or Type III coating, so the repair stays within the specification without full spray equipment.
The touch up coating must match the original type, grade, colour number and gloss level to maintain protection and visual consistency. Revision G lists repair coating on Navy weapon systems among the intended uses of the specification.
MIL-PRF-22750 Technical Data Sheet and MSDS
Each QPL-listed MIL-PRF-22750 product comes with a technical data sheet (TDS) specifying mix ratios, pot life, application thickness, cure schedule, and compatible primers. The TDS should always be consulted before application as these parameters vary between manufacturers and formulation types.
Safety data sheets (SDS, formerly MSDS) are required for all MIL-PRF-22750 products and must be available at the point of use. These cover handling precautions, personal protective equipment requirements, and disposal procedures for both the mixed coating and individual components.
Comparison with Related Coating Standards
MIL-PRF-22750 is one of several military coating specifications. The choice between them depends on the substrate, the operational environment, and whether the coating is a primer or a topcoat.
| Specification | Type | Typical Use |
|---|---|---|
| MIL-PRF-22750 | Two-component high-solids epoxy | Topcoat with excellent chemical resistance: interiors of aircraft and ground support equipment, weather-exposed equipment in Grade A, and repairs |
| MIL-PRF-23377 | High-solids epoxy primer | Corrosion-resistant primer applied under topcoats on aviation systems |
| MIL-PRF-85582 | Waterborne epoxy primer | Water-based alternative primer on aviation systems |
| MIL-DTL-53022 | Epoxy primer, lead and chromate free | Corrosion-inhibiting primer on pretreated steel |
| MIL-DTL-53039 | Single-component aliphatic polyurethane, chemical agent resistant | Exterior CARC topcoat on Army tactical equipment |
| MIL-PRF-85285 | Polyurethane | Aircraft and support equipment topcoat, good weathering performance |
In many coating systems, MIL-PRF-22750 serves as the topcoat over an epoxy primer, combining the chemical resistance and hardness of the epoxy with the corrosion inhibition of the primer. Where colour retention in sunlight matters most, a polyurethane topcoat is normally chosen instead: MIL-PRF-85285 on aircraft, MIL-DTL-53039 on Army tactical equipment.
Environmental and Regulatory Compliance
Modern revisions of MIL-PRF-22750 include strict limits on volatile organic compounds (VOCs) and hazardous materials. Revision G caps VOC at 340 g/L (2.8 lb/gal) as packaged, requires Types II and III to be VOHAP-free, and excludes lead and chromium compounds.
Revision G also bars benzene, ethylene glycol ethers and chlorinated solvents other than PCBTF. Class W, the water-based class, suits facilities operating under air quality regulations or seeking to reduce solvent emissions without sacrificing coating performance.
Need Military-Grade Lighting for Coated Equipment?
Betalight Tactical does not make or supply epoxy coatings. We supply the lamps fitted to the vehicles and equipment they protect, and the paint shop and the lamp meet at every repaint.
A lusterless film on a lens blocks light, and removing overspray with ketone solvents such as methyl ethyl ketone can swell a polycarbonate lens. Our guide on how to clean car lights lists the chemicals to keep off a lamp.
Housing colour can follow the paint scheme. Our military headlight is offered with black, green or tan mounting buckets to match camouflage or vehicle paint, and the range also covers military blackout lights and LED rear lights for tactical vehicles.
The lamp itself has its own performance specification: for LED lamps on military ground vehicles, see MIL-PRF-32212A. For specification advice, email info@betalight-tactical.com.
Frequently Asked Questions
Yes. DLA ASSIST lists the specification as active, with revision H dated 29 July 2025 and the next review due in July 2030. Revision H follows revision G of 2011, its 2014 amendment and an administrative notice of 2019. NAVAIR is the lead standardisation activity and the Army Research Laboratory the preparing activity. Always check the current QPL to confirm which products are currently qualified.
The specification does not state a service life. Its test hours, such as 1,000 hours of salt spray for Type III and 500 hours of accelerated weathering, are minimum qualification thresholds, not a service life prediction. Actual service life depends on surface preparation quality, the primer, coating thickness, exposure conditions, and whether the coating system is maintained and touched up when damage occurs.
Only Type III, the direct-to-metal formulation, which is qualified without a primer. Type II is designed to be applied over a qualified primer: revision G names MIL-DTL-53022 or MIL-DTL-53030 on pretreated steel and MIL-PRF-23377 or MIL-PRF-85582 on aviation systems. Applying Type II directly to bare metal reduces adhesion and corrosion protection significantly and is unlikely to meet the adhesion requirements of the specification.
It belongs to the interior side of the Army system rather than the exterior topcoat. The painting manual TM 43-0139 lists its predecessor, MIL-C-22750, as a chemical agent resistant epoxy for interior surfaces of vehicles, vans and shelters, with ramps and hatches that open outwards painted as exteriors. Exterior CARC topcoats are the polyurethanes MIL-DTL-53039 and MIL-DTL-64159, so check which the contract names.