API International manufactures a full line of NSF-61 certified stainless flanges, including ANSI/ASME Class 150 and AWWA Class D & E configurations in dual grades 304/304L and 316/316L stainless steel. We can review any custom products to determine if they fall within the scope of our NSF listing. Every part is manufactured domestically and certified to NSF/ANSI/CAN 61 for health effects and NSF/ANSI/CAN 372 for lead content.
NSF/ANSI/CAN 61 is the standard that sets strict limits on chemical leaching in drinking water systems. It’s verified through independent laboratory testing and on-site facility audits rather than a manufacturer’s own claim. NSF-61 certified flanges are typically also evaluated to NSF/ANSI/CAN 372 for lead content.
Evaluating Chemical Leaching
The Paired Requirement
Independently Tested and Audited
API International has launched CleanLine, a new line of NSF-certified products developed for drinking-water and clean-water applications. CleanLine products are certified to NSF/ANSI/CAN 61 for drinking-water system health effects and NSF/ANSI/CAN 372 for lead-content requirements.
Explore CleanLineAny project where a flange sits inside a potable water system benefits from NSF-61 certification. In most states, it’s required rather than optional.
Health Effects Scope
Evaluates the full range of chemical contaminants a product might leach into drinking water, not lead content specifically.
Lead Content Scope
Verifies a single, critical requirement: a maximum weighted-average lead content of 0.25%, the federal lead-free definition.
What Most Buyers Actually Need
With limited exemptions, products certified to NSF-61 must also meet NSF-372, which is why a genuinely certified flange carries both marks together.
U.S. States and Canadian Provinces and Territories have legislation, regulations, or policies requiring compliance with, or certification to, NSF/ANSI/CAN 61 for components that contact drinking water.
Still have a question about NSF-61/372 certification or how it applies to your project? Contact our team.
NSF-61 evaluates whether a product leaches contaminants into drinking water above acceptable levels. It's typically paired with NSF-372, which verifies lead content separately.
NSF-61 covers the full range of chemicals a product might leach into drinking water. NSF-372 verifies a single, critical requirement: a maximum weighted-average lead content of 0.25%. The two are usually required together, not as alternatives to each other.
Yes. Certification means an independent third party tested the product and audited the facility. A self-declared "compliant" claim has no independent verification behind it.
Yes. Both flange families are evaluated to the same standard when built for potable water applications, regardless of whether they follow ANSI/ASME B16.5 or AWWA C207 dimensional specifications.
304L and 316L stainless steel, selected for corrosion resistance and compatibility with NSF-61 health-effects requirements.
Yes. Every flange in the CleanLine product line is manufactured in the United States.
Contact API International's experienced sales team, and we will help you select the right NSF-61 certified flange for your application. You can also explore our full range of certified products in our online product catalog, or reach out for custom flange options designed to meet your project specifications. Get connected with a dedicated sales representative today, or call us at 503.692.3800.
• Custom Bolt Holes, Overbore, Counterbore, Tapped, Welds, O-ring Grooves, Threads, Special Serrations, Bevels, Chamfers
• Metric Parallel, Metric Tapered, Parallel (BSPP), Taper Thread (BSPT), UN/UNF/UNC Thread, NPT (National Pipe Thread)
• MWD
• Contact API’s engineering department for exact specifications and tolerances.
Plastic: Delrin, POM, Lexan, Nylon 66, Nylon 6, PEEK, PP, PE, Acetal
Rubber: EPDM, Neoprene, Buna-N, Viton
Aluminum: A2011, A2024, A2017, A5052, A5056, A6061, A6063, A6463, A6082, A7075
Copper: 3600, 3604, 3771
Titanium: 1-28
Steel Series:
• Ductile Iron: ASTM A536
• Carbon/Mild Steel: A105, A36, A516-70, A572-50, etc.
• Stainless Steel:
- 300 Series – 303, 304, 304L, 316, 316L
- 400 Series – 420J2, 430, 434, 442
Special Metals: Hastelloy, Inconel, Incoloy, Duplex 2205, Super Duplex 2507, Chrome Steel, alloys, or their equivalents
Stock Finish, Spiral Serrated (Phonographic), Concentric Serrated, Smooth Finish, Cold Water Finish, MWD, Phonographic
Dipped, Nickel Plating, Zinc Plating (clear, yellow, black, red, blue), Super Agitine, Powder, Painted, Galvanized, Epoxy, Lacquer
Water/Wastewater, Irrigation, Agriculture, HVAC, Marine, Exhaust, Mining, Energy/Power Generation
Plate:
• Materials: Stainless Steel, Carbon Steel
• Size: 2–202”
Forged:
- Ring Rolling:
• Materials: Carbon Steel, Stainless Steel, Duplex
• Size: 2–202”
Cast:
- Centrifugal Casting (Industrial):
• Material: Stainless Steel
- Continuous Casting:
• Material: Stainless Steel
- Sand Casting:
• Material: A536, Stainless Steel, Ductile Iron
Machining: Milling, Turning, Facing, Boring, Drilling, Tapping, Counter Sinking, Laser Cutting, Water Jet, Plasma Cutting
Products | Type | Materials | Size Range |
|---|---|---|---|
Flanges | Flat-Face, Raised-Face, & Plate: Slip-On/Ring Weld, Neck, Blind, Socket Weld, Orifice, Reducing, Threaded | See Materials List | .5–202″ |
Gaskets | Molded, Extruded, sheet | EPDM, Buna-N, NBR, Non-Asbestos (GNA), Red Rubber (GRR), Viton | .5–60″ |
Screens For Filters | Basket Screens and Cone Screens (Perforated, Mesh) | Galv. Carbon Steel, Carbon Steel, Stainless Steel | 6”D x 8’-H |
Rings | Exhaust Rings (Marmon Flanges for DPF Filters) | Carbon Steel, Stainless Steel, Aluminum | 1–16” |
Seamless Rolled Rings | Forged | Carbon Steel, Stainless Steel, Aluminum | 1–165” |
Square Hole Rings | Repair Couplers | Stainless Steel, Carbon Steel, Galvanized, Epoxy Coated | 3–32” |
Fabricated Assemblies | Weldments, Pipe Spools, Valve Bodies, Silencer Housings | Carbon Steel, Stainless Steel | 2–24” |
Long/Short Radius Elbows | EN 10253-2–S235, P235GH–P265GH–P265NL and ASTM A234, WPB, WPC/ A420 WPL6, WPL3/ A860 WPHY52/ ASTM A234 WP11, WP22, WP5, WP9–16Mo3 | 304L & 316L Stainless Steel | (45° & 90°): OD: 21.3mm (1/2”)–3048mm (120”) WT: Up to SCH. XXS/160 |
Miscellaneous | Tubesheets / Diffuser Plates / Baffles / Ferrules / Sleeves / Pins | Carbon Steel, Stainless Steel, Duplex | .5–104” |
Who we are
API International is a manufacturer and engineering solutions provider that specializes in flanges, expansion joints, valve accessories, other pipe fittings, and custom-fabricated parts. We offer a wide variety of AIS & imported flanges along with other industrial pipe fittings and accessories. Customers turn to us when they need quick delivery of parts and are looking for a higher level of customer service. Standard parts are stocked in one of our conveniently located warehouses for quick distribution throughout the United States.
