FabTek’s finish system is certified to 2000-hour salt spray, and buyers reasonably ask what that means. It is not a warranty period and it is not a number of years. It is a laboratory test with a specific method, a specific failure criterion and a specific standard behind it — explained here.
Need this built to your spec? Call 601.892.5017 or email collin.t@fabtekindustries.com — send the drawing and we’ll quote it.
- A 2000-hour salt spray rating means scribed test panels of the complete finish system survived 2,000 hours of ASTM B117 continuous salt fog with rust creepage from the scribe and blistering within the specified limits.
- IEEE C57.12.28, the enclosure-integrity standard for pad-mounted equipment, requires 1500 hours of B117 salt spray among its coating tests; 2000 hours exceeds it. C57.12.29 (coastal) is more severe.
- Salt-spray hours rank coating systems and verify process control; they are not a direct prediction of service years.
- What Gauge Steel for a NEMA 3R Walk-In Enclosure?
- ASTM A123 vs. A153: Which Galvanizing Spec Applies?
- Minimum Bend Radius for 5052 Aluminum Sheet
- Powder Coat Film Thickness for Outdoor Electrical Enclosures
- IEEE 2000-Hour Salt Spray: What the Rating Actually Means (you are here)
- AWS D1.1 vs. D1.3 vs. D1.6: Which Welding Code Applies?
- Bolt-Hole Tolerances for Substation Steel Structures
- Non-Segregated Bus Duct: Ampacity, Bar Size and Housing
- Material Certs and Heat Numbers: What Traceability Means
- How to Spec Anchor-Bolt Patterns for Equipment Stands
The answer
A “2000-hour salt spray” finish is one whose complete system — substrate, pretreatment, and powder or paint at the specified film thickness — was applied to test panels, scribed through to bare metal, and exposed to 2,000 hours of continuous 5% salt fog at 35 °C per ASTM B117, after which the rust creepage from the scribe, blistering and face rust were measured and found within the acceptance limits of the governing standard. For pad-mounted electrical enclosures that standard is IEEE C57.12.28, which requires 1500 hours; a system certified at 2000 hours has exceeded the requirement with margin. FabTek’s powder coat system carries that certification, which is why IEEE 2000-hour salt spray appears on our quality page alongside ISO 9001 and AWS.
The test: ASTM B117
B117 is the Standard Practice for Operating Salt Spray (Fog) Apparatus. Panels hang at an angle in a closed chamber where a 5% sodium chloride solution is atomized into a continuous fog at 35 °C (95 °F); the fog condenses and runs off the panels constantly for the duration. It is an accelerated, aggressive exposure that has no direct equivalent outdoors — real weather cycles wet and dry, which is why cyclic tests such as ASTM G85 and GM9540P exist for automotive work — but it is the universal benchmark for electrical-enclosure coatings because it is repeatable, comparable across suppliers and referenced by the IEEE enclosure standards.
What is measured
- Scribe creepage — how far rust and coating undercutting have crept from the scribe line, in millimeters or fractions of an inch, per ASTM D1654. This is the primary criterion; it measures the system’s ability to stop corrosion spreading from damage.
- Blistering — size and density of blisters on the unscribed face, per ASTM D714.
- Face rust — rust on the unscribed surface, per ASTM D610.
- Adhesion after exposure — whether the coating still bonds after the salt fog has worked at it.
A system “passes” a given number of hours when all of these stay within the limits the standard sets. Because the scribe is the hard part, the pretreatment and primer system matter as much as the topcoat — which is why film thickness alone does not predict salt-spray performance.
IEEE C57.12.28 and C57.12.29
IEEE C57.12.28, Standard for Pad-Mounted Equipment — Enclosure Integrity, sets the requirements for pad-mount transformer and switchgear cabinets in public spaces: tamper resistance (pentahead hardware, pry and pull tests), and a coating-system qualification that includes salt spray (1500 hours), humidity, ultraviolet exposure, crosshatch adhesion, impact, abrasion, gravelometer and oil resistance tests. IEEE C57.12.29 is the companion standard for coastal environments, with more severe corrosion requirements including longer salt-spray exposure, for enclosures near salt water or heavy de-icing salt. A utility spec that says “coating per C57.12.28” is asking for the whole test suite, not just the hours. FabTek’s pad-mount transformer cabinets are built and finished to it.
Hours vs. years
Salt-spray hours do not convert to years of service; the environments are too different and the test too aggressive. What the hours do is rank systems — a 2000-hour system will outlast a 500-hour system in the same location — and verify process control, because a coating line that passes 2000 hours on qualification panels is a line whose pretreatment, film build and cure are under control. For the buyer, the practical use is to require a qualified system with documented salt-spray results and to require the fabricator to run the same process in production, checked by DFT and cure tests on real parts.
How to write it
“The coating system shall be qualified to the coating-system requirements of IEEE C57.12.28 (or C57.12.29 for coastal sites), including a minimum of [1500 / 2000] hours salt spray per ASTM B117 with scribe creepage not exceeding [limit] per ASTM D1654 and no blistering per ASTM D714. Supplier shall furnish the qualification report and shall demonstrate that production parts are processed with the qualified pretreatment, powder and film thickness.”
How FabTek handles it: Our pretreatment-plus-powder system is qualified to 2000 hours ASTM B117 salt spray with scribe creepage within IEEE C57.12.28 limits; production parts are run through the same pretreatment and powder, with DFT and cure checked and recorded. If your drawing calls for something different, send it — we build to print. Request a quote.
Frequently asked questions
What does 2000-hour salt spray mean?
That scribed test panels of the complete finish system — substrate, pretreatment and coating at the specified thickness — survived 2,000 hours of continuous 5% salt fog at 35 °C per ASTM B117 with rust creepage from the scribe, blistering and face rust within the acceptance limits of the governing standard.
What salt spray hours does IEEE C57.12.28 require?
IEEE C57.12.28, the enclosure-integrity standard for pad-mounted equipment, requires 1500 hours of ASTM B117 salt spray as part of a coating qualification suite that also includes humidity, UV, adhesion, impact, abrasion, gravelometer and oil-resistance tests. IEEE C57.12.29 for coastal environments is more severe.
How many years does 2000 hours of salt spray equal?
There is no direct conversion; salt spray is an accelerated laboratory exposure that ranks coating systems and verifies process control rather than predicting service life. A 2000-hour system will outlast a lower-rated system in the same environment, but actual years depend on the site.
