Acetal Copolymer FDA Food-Grade — POM-C Compliance Guide

Acetal copolymer (POM-C) offers broader FDA food-contact compliance options than acetal homopolymer (Delrin), and critically, it handles hot-water food-contact service — dishwashers, hot-water valves, coffee machine internals — where Delrin degrades. Natural-color Celcon and Hostaform grades broadly meet 21 CFR 177.2480 without requiring a specific "SA" grade designation, and NSF 51/61 certified POM-C grades are widely available. This page covers the regulatory framework, hot-water temperature limits, grade verification approach, and documentation requirements.

At a glance:

• FDA 21 CFR 177.2480: covers acetal copolymer for repeated-use food contact
• Many natural-color Celcon M90 and Hostaform C 9021 grades meet 21 CFR 177.2480 — verify lot
• Hot-water advantage: POM-C rated to ~160°F (71°C) standard grades; heat-stabilized grades to ~180°F (82°C)
• This exceeds Delrin (POM-H) food-contact hot-water limit of ~140°F (60°C)
• NSF 51 (food equipment) and NSF 61 (drinking water) certified grades available
• EU Regulation 10/2011 Declaration of Compliance available for European applications

FDA 21 CFR 177.2480 — What It Covers

21 CFR 177.2480 (Acetal resins) governs both POM homopolymer and POM copolymer in repeated-use food-contact applications. For copolymers, the regulation allows:

• Formaldehyde, trioxane, and specified comonomers (including 1,3-dioxolane and ethylene oxide) as polymerization monomers
• Listed stabilizers, antioxidants, nucleating agents, lubricants, and colorants as adjuvant substances
• Specified extraction limits for food simulants

The key compliance implication: a Celcon or Hostaform grade that uses only CFR-listed adjuvants qualifies under 21 CFR 177.2480 regardless of whether the manufacturer has designated it with an "SA" or equivalent food-grade suffix (unlike Delrin, which reserves "SA" grades specifically for this purpose). This means the compliance determination is a formulation question, not simply a grade-name question.

Which Grades Are FDA-Compliant?

Celcon (Celanese)

Standard natural-color Celcon M90 and M25 grades are generally formulated with FDA-listed adjuvants. Celanese provides FDA compliance letters confirming 21 CFR 177.2480 status for standard natural grades upon request. Black and colored grades may use non-listed pigments — verify grade-specifically.

Celcon grades with broad FDA availability:

• Celcon M25 (high-MW, extrusion grade): natural color — generally compliant; verify lot
• Celcon M90 (standard injection molding): natural color — generally compliant; verify lot
• Celcon M270: natural color — generally compliant; verify lot
• Lubricated grades (M90-44, etc.): lubricant additive may not be CFR-listed — verify specifically

Hostaform (Ticona/Celanese)

Hostaform C 9021 and C 13021 in natural (white) color are widely used in food-contact applications in Europe and are formulated to meet EU Regulation 10/2011 (which is broadly compatible with 21 CFR requirements). For US applications, request Celanese's 21 CFR 177.2480 compliance letter specifically for the Hostaform lot.

Heat-Stabilized Grades for Hot-Water Food Contact

For dishwasher-temperature and hot-water service (140–180°F, 60–82°C):

• Hostaform C 9021 HS (heat-stabilized): designed for sustained hot-water contact; verify FDA compliance letter
• Celanese heat-stabilized POM-C variants: available; verify current grade nomenclature and FDA status with Celanese

Standard (non-heat-stabilized) POM-C grades are suitable to approximately 160°F (71°C) in sustained food-contact water service. Heat-stabilized grades extend this to ~180°F (82°C).

Hot-Water Compliance: POM-C vs. POM-H (Delrin)

This is the key FDA compliance engineering decision point between the two acetal variants:

The engineering implication: For any food-contact application involving hot water — dishwashers, hot-water dispensers, vending machines, coffee equipment, hot-fill packaging, commercial food steamers — acetal copolymer is the correct material. Delrin is not suitable for these applications.

NSF Certification

NSF/ANSI 51 — Food Equipment Materials

NSF 51 is the independent certification for plastics in direct and indirect food contact in commercial food service equipment. Celcon and Hostaform grades carry NSF 51 listings; verify the specific grade and current listing status at NSF's Product and Service Listings database before specifying.

NSF/ANSI 61 — Drinking Water System Components

NSF 61 applies to POM-C components in drinking water systems: water meter bodies, valve seats, pipe fittings, and related components. Selected Celcon and Hostaform grades carry NSF 61 certification. Certification is lot-specific; request current NSF listing documentation with each shipment.

USDA Acceptance

USDA-accepted acetal copolymer grades are used in federally inspected meat and poultry processing equipment. The same FDA compliance framework applies; USDA additionally requires:

• Components must meet the FDA food-contact requirements
• Materials in direct product contact must be non-toxic and cleanable
• POM-C's chemical resistance to USDA-approved cleaning agents (alkali-based sanitizers) is an advantage over POM-H here — copolymer resists alkaline cleaners better

EU and International Food-Contact Compliance

EU Regulation 10/2011 (Plastics Food Contact Materials)

EU 10/2011 is the European framework regulation for plastics in food contact. POM (both homo- and copolymer) is covered under the Union List. Celanese provides Declarations of Compliance (DoC) for Hostaform grades under EU 10/2011 for European applications. Request the DoC when sourcing for EU-regulated end markets.

BfR (Germany) and Other National Standards

BfR VIII Recommendation (Polyoxymethylene) is the German national supplement. Hostaform natural grades generally comply; request BfR documentation from the European supply chain.

British Standards

Following Brexit, Great Britain has adopted retained EU food-contact law for plastics. The compliance pathway is the same as EU 10/2011 for POM-C.

Documentation Requirements for Food-Grade POM-C

For each shipment of food-contact acetal copolymer, request:

1. Certificate of Conformance (CoC): Grade designation, lot number, polymer type (POM-C)
2. FDA 21 CFR 177.2480 compliance letter: Manufacturer's statement confirming the specific grade meets CFR 177.2480 (Celanese or BASF letterhead)
3. NSF listing documentation (if required): Current NSF product listing print or reference number
4. EU Declaration of Compliance (if EU-regulated application): Per EU Regulation 10/2011 framework

Write your purchase orders to specify: "Acetal copolymer (POM-C), natural color, [grade if specific], FDA 21 CFR 177.2480 compliant, certificate of conformance required. [Add NSF 51 or NSF 61 if applicable.]"

Comparing POM-C vs. POM-H (Delrin SA) for Food Contact

For cold-water-contact, low-cycle applications where fatigue endurance matters: Delrin SA is a viable choice. For everything else involving water — especially hot water — acetal copolymer FDA-compliant grades are the better engineering choice.

More related guides

Compliance and regulatory

• Delrin FDA Food-Grade (POM-H)
• PEEK FDA and USP Class VI Compliance

Industries

• Food Processing Plastics
• Water Treatment Plastics

Frequently asked questions — Acetal Copolymer FAQ