跳至内容 
Two different certifications, two different questions. Here’s what each one actually checks — and why US-bound brass usually needs both.
Short answer: NSF/ANSI 61 tests whether a fitting leaches harmful substances into water. NSF/ANSI 372 tests whether the alloy’s lead content stays under the US legal limit. They measure different things, and most potable-water brass sold in the US needs both.
Key Takeaways
- NSF/ANSI 61 = leaching/health-effects test. NSF/ANSI 372 = lead-content calculation, capped at 0.25% weighted average.
- The 0.25% limit is US federal law (Safe Drinking Water Act §1417, effective 2014) — NSF 372 verifies compliance with it.
- Solder and flux have a stricter separate limit: 0.2%, not 0.25%.
- Common lead-free alloys: C87850, C69300. Traditional C36000 free-cutting brass (~2.5–3.7% Pb) does not qualify.
What Does NSF/ANSI 61 Actually Test?
NSF/ANSI 61 is a broad leaching standard. It doesn’t target lead specifically — it checks whether any wetted-surface material releases regulated contaminants into water above safe thresholds.
- Covers lead, arsenic, cadmium, chromium, copper, mercury, nickel, and other metals plus organics
- Tests the finished component under simulated water-contact conditions, not just the raw alloy
- Applies to plastic, rubber, and coated components too — not brass-specific
What Does NSF/ANSI 372 Actually Test?
NSF/ANSI 372 checks one thing: how much lead is in the alloy, using a weighted-average calculation across all wetted surfaces (the “Annex G” method) — not a leaching test.
- Pass threshold: 0.25% lead, weighted average, on wetted surfaces
- Verifies compliance with US Safe Drinking Water Act §1417, as amended by the 2011 Reduction of Lead in Drinking Water Act (effective January 4, 2014)
- Solder and flux face a stricter, separate limit of 0.2% (EPA)
Do You Need Both Certifications?
For potable-water brass sold into the US, yes — in almost every case.
| Standard | What it proves | Required for US potable water? |
|---|---|---|
| NSF/ANSI 61 | Component doesn’t leach harmful substances | Yes |
| NSF/ANSI 372 | Alloy meets the 0.25% lead-content limit | Yes |
One certificate alone leaves a gap: a component can pass leaching tests while still using a leaded alloy over the legal limit, or vice versa. Always request both certificates for the exact SKU you’re ordering — certification is product-specific, not brand-wide.
Fenilo’s brass insert fittings and brass cartridges are available in both leaded and lead-free alloy options depending on your destination market.
Which Brass Alloys Are Actually Lead-Free?
- C87850 — silicon-bronze alloy, marketed as a lead-free replacement for leaded C93200, NSF/ANSI/CAN 372 compliant
- C69300 — silicon-brass alloy compliant with NSF/ANSI/CAN 61-2022 and the federal 0.25% rule
- C36000 (traditional free-cutting brass, ~2.5–3.7% lead) — good machinability, but does not meet the lead-free requirement for US potable-water parts
If a supplier quotes “NSF certified” without naming which standard, ask directly: 61, 372, or both? The answer changes what alloy you’re actually getting.
A practical look at how lead-free and leaded brass valves differ and when each is required.
Sourcing lead-free brass for the US market?
Fenilo can supply brass fittings and inserts in NSF/ANSI 61 and NSF/ANSI 372 compliant alloys, with certificates matched to your specific SKU.
Request Certification DocumentsFAQ
Is NSF/ANSI 372 the same as “lead-free”?
Effectively yes — it’s the certification that verifies a product meets the legal 0.25% lead-content definition of “lead-free” under US federal law.
Can a product be NSF/ANSI 61 certified but not lead-free?
Yes. NSF/ANSI 61 tests leaching, not lead content specifically, so a component can pass it while still exceeding the 0.25% lead-content limit. That’s why both certifications matter.
Does this apply outside the US?
The 0.25% rule is US federal law. Other markets use different frameworks — see our comparison of WRAS vs NSF certification for UK/EU vs US markets.
Bottom line: ask for NSF/ANSI 61 and 372 certificates by SKU, not by brand, before you ship brass fittings into the US. For a look at region-specific rules beyond NSF, see California AB 1953 and the 0.25% lead rule.