Does this predict corrosion resistance?

No. It reports observed results for the assessed specimens under the specified protocol. It supplies no service-life prediction.

What if exposure is incomplete?

Treat the observed pass rate as provisional. Complete the exposure required by the protocol before making final specimen disposition.

How should failed specimens be counted?

Apply the same fixed acceptance criteria to each specimen in the set. Enter whole observed counts from the test record.

Does a passing specimen set prove outdoor performance?

No. ASTM B117 warns that standalone salt spray results generally cannot predict natural environment behavior. Appropriate corroborating exposure evidence is needed.

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Corrosion Test Pass Rate Calculator

Report observed passes among specimens assessed under one specified corrosion test protocol. Check exposure completion and an entered failure allowance before making a specimen disposition.

What this calculator does

Report observed specimen pass rate and exposure completion under one specified corrosion test protocol.

Formula used

Passed specimens = tested specimens − observed failures
Observed pass rate = passed specimens ÷ tested specimens × 100
Observed failure rate = failed specimens ÷ tested specimens × 100
Exposure still required = maximum of zero and required hours − observed hours
Failure headroom = allowed failures − observed failures

Inputs explained

Tested Specimens: Whole specimens assessed under one specified test protocol.
Failed Specimens: Observed failures using the fixed specimen acceptance criteria.
Observed Exposure: Completed exposure duration for the assessed specimens.
Required Exposure: Exposure duration specified by the same test protocol.
Allowed Failed Specimens: Entered failure allowance for this specimen set.

How to use the result

Best suited to observed corrosion specimen summaries, test exposure completion checks.
Does not predict natural environment corrosion resistance or service life. Observed proportions provide no population confidence interval.

Current U.S. benchmarks

The producer price index for industrial chemicals stands at 336.006 (BLS, Aug 2026), up 13.3% from a year earlier. Quotes priced off last quarter's material cost miss this move.
The U.S. has 14,543 chemical manufacturing establishments employing about 911,245 workers (Census County Business Patterns, 2023).

Common questions

Does this predict corrosion resistance? No. It reports observed results for the assessed specimens under the specified protocol. It supplies no service-life prediction.
What if exposure is incomplete? Treat the observed pass rate as provisional. Complete the exposure required by the protocol before making final specimen disposition.
How should failed specimens be counted? Apply the same fixed acceptance criteria to each specimen in the set. Enter whole observed counts from the test record.
Does a passing specimen set prove outdoor performance? No. ASTM B117 warns that standalone salt spray results generally cannot predict natural environment behavior. Appropriate corroborating exposure evidence is needed.

Last reviewed 2026-10-06.