NSF 61 O-Ring Selection Guide
NSF 61 O-Rings and other Materials for Potable Drinking Water Irrigation Compliance Seals from Experts
We are experienced with the demanding applications found in the drinking water and irrigation industry.
Selecting the best material or seal design can increase service life and predictability,
and reduce contamination, resulting in higher efficiency.

Marco Rubber manufactures NSF 61 O-rings, NSF 61 Gaskets, NSF 61 rubber seals and custom-designed components from a range of NSF 61 compliant rubber materials, including NSF 61 Buna-N, NSF 61 EPDM, NSF 61 Viton®.
NSF 61 – ANSI 61 – NSF 51
NSF/ANSI Standard 61 is an US Standard issued by the National Sanitation Foundation which defines the acceptable levels of contaminating substances and impurities that may leach or migrate from components and devices into drinking water systems. Marco Rubber stocks NSF61 compliant O-rings but also supplies a variety of NSF 61 compliant materials in standard and non-standard configurations, please contact our sales and engineering. www.nsf.org/business/search_listings
WRAS - Water Regulations Advisory Scheme
Materials approved for British drinking water applications in the United Kingdom must satisfy the requirement of BS6920 for the Water Regulations Advisory Scheme. The testing regime for WRAS approval is different to FDA testing, in that it requires that elastomer products must also be tested to ensure that they do not promote the propagation of bacteria. www.wras.co.uk
KTW
In Germany, KTW specifies the requirements of elastomers in potable water as set out by the German Technical and Scientific Association for Gas and Water (DVGW) in the regulation "Arbeitsblatt W270". Drinking water approvals vary from country to country, although it is common for one country to use a material that has been approved under the standard of another country. Our Technical Team can advise on which products are suitable for drinking water applications against a number of national standards. www.dvgw.de
ACS XP P 41-250
Attestation de conformité sanitaire ACS XP P 41-250 is a system developed by the French health authorities to evaluate and certify the sanitary conformity and suitability of products which come into contact with drinking water destined for human consumption
Popular Products:
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Contact us for help selecting from these and the many more available.
CPD# | MATERIAL | DUROMETER (SHORE A) | COLOR | LOW TEMP (F) | HIGH TEMP (F) | FDA* | USP CLASS VI** | NSF61 | USDA 3A | METAL DETECTABLE |
---|---|---|---|---|---|---|---|---|---|---|
EPDM | 70 | Black | -65 | 300 | ![]() | ![]() | ||||
Peroxide cured EPDM, Different Durometer , KTW, WRAS standards available | ||||||||||
EPDM | 70 | White | -65 | 300 | ![]() | ![]() | ![]() | |||
Wide range of compliance | ||||||||||
EPDM | 70 | Black | -40 | 250 | ![]() | ![]() | ![]() | |||
Wide range of compliance | ||||||||||
EPDM | 70 | Black | -65 | 300 | ![]() | ![]() | ![]() | |||
Formulated for Chloramine Resistance. Can be manufactured in custom shapes with minimal setup charge. | ||||||||||
NBR | 70 | Black | -30 | 250 | ![]() | |||||
Available in many durometers and colors | ||||||||||
NBR | 70 | White | -30 | 250 | ![]() | |||||
Available in many durometers and colors | ||||||||||
NBR | 70 | Black | -30 | 250 | ![]() | ![]() | ||||
KTW, WRAS and other standards available. | ||||||||||
NBR | 70 | Black | -30 | 250 | ![]() | ![]() | ||||
Metal detectable for contamination detection sensors(additional colors available) | ||||||||||
VMQ | 70 | Orange | -75 | 400 | ![]() | |||||
Available in many durometers and colors | ||||||||||
VMQ | 70 | Clear Translucent | -75 | 400 | ![]() | |||||
Clear Translucent, available in many durometer and color choices. | ||||||||||
VMQ | 70 | Clear Translucent | -75 | 400 | ![]() | ![]() | ||||
Clean room manufactured, platinum cured (specific base materials and cleanroom packaging options available) | ||||||||||
VMQ | 70 | Clear Translucent | -65 | 400 | ![]() | ![]() | ||||
Commercial manufactured, platinum cured (cleanroom manufacturing and packaging options available) | ||||||||||
VMQ | 70 | White | -75 | 480 | ![]() | ![]() | ||||
Cleanroom manufactured, Lower cost than clear | ||||||||||
FKM | 75 | White | -15 | 437 | ![]() | ![]() | ||||
Cleanroom manufacturing and packaging options available | ||||||||||
FKM | 70 | White | -15 | 437 | ![]() | ![]() | ![]() | |||
Steam Resistant Terpolymer, Also available in black | ||||||||||
FKM | 70 | Black | -15 | 392 | ![]() | ![]() | ||||
Metal detectable for contamination detection(additional colors available) | ||||||||||
FFKM | 75 | Black | -5 | 610 | ![]() | |||||
FDA compliant, higher temperature resistance, wide chemical compatibility. Compare to Kalrez® 6230, Kalrez® LS222 | ||||||||||
FFKM | 75 | Black | 5 | 525 | ![]() | ![]() | ||||
Greater temperate resistance range. Compare to Kalrez® 6230, Kalrez® LS222 | ||||||||||
FFKM | 75 | White | 5 | 500 | ![]() | ![]() | ||||
USP Class VI and FDA compliant white FFKM with wide range compatibility. Compare to Kalrez® 6221, Kalrez® LS205, Chemraz® 625 |
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*FDA compliance per 21 CFR 177.2600 parts A-D, E&F approved compounds available upon request. **USP <87> and USP <88> approved compounds available upon request.
The temperature ranges presented above are approximations for dry air service only and should not be used to determine design specifications or end-use temperature limits. Actual temperature range of a compound in an end-use application is highly dependent on part type, hardware configuration, applied forces, chemical media, pressure and thermal cycling effects, and other factors. The most practical way of determining an end-use temperature range is testing in the actual application conditions. Consult a Marco Engineer for more details.