EPDM vs NBR vs FKM seals in a direct practical comparison

Anyone selecting seals often decides on service life, maintenance effort and process reliability at the same time. In practice, it is therefore rarely enough simply to take any elastomer material. EPDM, NBR and FKM differ significantly in media resistance, temperature behaviour, weather resistance and cost-effectiveness. These very differences are relevant in everyday use, for example in mechanical engineering, in vehicle technology, in systems with cleaning chemicals or in outdoor areas.

If you would like to select seals for specific applications, it is also worth looking at suitable solutions for rubber seals, at industry-specific requirements for seals for mechanical engineering, at rubber sheets as a material base and at the general guide with further technical articles.

Quick decision for practice

• EPDM is suitable for water, weather, ozone and outdoor applications.
• NBR is suitable for oil, grease, hydraulics and many fuel-related standard applications.
• FKM is suitable for high temperatures, aggressive media and long service lives.

This initial classification saves time. For a clean selection, what then counts is the medium, temperature, mechanical load, installation situation and desired service life.

Why the material comparison is so important in practice

Many problems arise because the material is chosen only roughly by gut feeling. A seal often still performs inconspicuously in the first test, but then fails under temperature changes, oil exposure, UV influence or contact with cleaners. This is exactly where practice separates from theory.

EPDM plays to its strengths above all with water, weather, ozone and many polar media. NBR is the classic material for oil- and fuel-exposed applications. FKM becomes interesting when high temperatures, aggressive media or particularly demanding operating conditions are present. A clean comparison therefore saves not only purchasing costs, but above all downtime, complaints and unnecessary material changes.

EPDM, NBR and FKM in brief

EPDM

EPDM is a versatile synthetic rubber for applications with water, steam in suitable areas, diluted acids and alkalis as well as for continuous use outdoors. The material is very resistant to ozone, UV radiation and weather. It is therefore frequently used in construction, in ventilation and sanitary systems and in external seals. For applications with oils, fuels and many mineral-oil-based media, however, EPDM is usually the wrong choice. For more depth, the page EPDM seal is also a good fit, as is the article on application areas for EPDM seals.

NBR

NBR is one of the most important elastomers in the technical sealing sector. The material is particularly suitable for contact with oils, greases, fuels and many hydrocarbons. Typical fields of use are in mechanical engineering, in hydraulic systems, in units, pumps and in the automotive environment. NBR is cost-effective, mechanically resilient and a very good solution for many standard applications. The material shows weaknesses with weather, ozone and heavy UV exposure. For classification within the range, the page NBR seal as well as NBR is useful.

FKM

FKM, often also mentioned in connection with Viton, is the high-performance material among the three compared materials. FKM convinces at high temperatures, with many chemicals, oils, fuels and in particularly demanding industrial environments. The material is more expensive than EPDM and NBR, but offers a significantly higher level of safety in critical applications. Where media are aggressive or temperature reserves are required, FKM is often the more cost-effective solution over the service life. The page FKM seal is a useful complement.

FKM and Viton – are they the same?

In practice, people frequently search for Viton vs NBR or Viton vs EPDM. Viton is not a separate base material alongside EPDM, NBR and FKM, but a well-known trade name in the FKM environment. For the technical comparison, it is therefore important to note: anyone comparing Viton with NBR or EPDM is essentially comparing FKM with NBR or FKM with EPDM. Especially at higher temperatures, chemical exposure and long maintenance intervals, the decision therefore often falls in favour of FKM.

EPDM vs NBR vs FKM – which material is better?

There is no universally best material in practice. EPDM is better for water, UV, ozone and outdoor areas, NBR is better for oil, grease and many mechanical engineering applications, FKM is better for high temperatures, aggressive chemicals and particularly demanding operating conditions. Anyone who selects the material to suit the medium and the real load achieves longer service lives and lower follow-up costs.

Direct comparison of the most important properties

Criterion	EPDM	NBR	FKM
Temperature range (approx.)	-40 °C to +120 °C	-30 °C to +100 °C	-20 °C to +200 °C
Shore hardness (typical)	60–80 Shore A	60–90 Shore A	70–90 Shore A
Water and weather resistance	very high	low to medium	good
Ozone and UV resistance	very high	weak	good
Resistance to oils and fuels	weak	very high	very high
Chemical resistance	good with many polar media	good with oil-based media	very high with many aggressive media
Cold flexibility	good	medium	medium
Mechanical resilience	good	good to very good	good
Pressure resistance	good	very good	very good
Price level	low to medium	low to medium	high
Typical operating environment	Outdoor area, water, sanitary, construction	Hydraulics, oil, mechanical engineering	Chemicals, high temperature, demanding industry

The table already shows the basic pattern: EPDM for water, weather and outdoor applications, NBR for oil and fuel, FKM for temperature and chemical exposure at a high level. In practice, however, never just one criterion decides. What is always relevant is the combination of medium, temperature, pressure, movement, installation situation and desired service life.

Media resistance in practical comparison

EPDM with water, cleaning media and outdoor applications

EPDM is very well suited to water applications, many diluted acids and alkalis as well as environments with moisture, ozone and weather. Particularly with external rubber seals and weather-exposed rubber sheets, the material plays to its strengths. The material is therefore widely used in many outdoor applications and in building services. As soon as mineral oils, diesel, petrol or greasy media come into play, however, its suitability drops significantly. The seal can then swell, change its mechanical properties or fail prematurely.

NBR with oil, grease and fuel

NBR is the classic material when oil-based media dominate. In technical applications with contact to lubricants, hydraulic media and mineral-oil-based media, NBR is frequently the first choice, especially with seals for mechanical engineering. In hydraulic systems, with pumps, compressors, lines and technical units, NBR is often the first candidate. In these areas, the material delivers a strong ratio of performance to cost. In outdoor areas or with heavy ozone and UV exposure, however, NBR becomes less attractive.

FKM with chemically demanding media

FKM is frequently chosen when standard elastomers reach their limits. For demanding projects with high chemical or thermal load, it is also worth checking suitable FKM seals. This concerns aggressive chemicals, high thermal loads, fuels, oils and applications with particularly high requirements for ageing resistance. This is precisely why FKM is often found in the process industry, chemicals, special automotive applications and thermally highly stressed components. The higher material price quickly becomes relative if this reduces failures, maintenance intervals and material changes.

Temperature behaviour in direct comparison

In many applications, the temperature range is the point at which wrong decisions show up. A seal can be fundamentally suitable for the medium and nevertheless fail because continuous or peak temperatures were not properly taken into account.

EPDM works reliably in many standard applications and covers typical temperature ranges well in water, sanitary or outdoor applications. NBR is also suitable for many industrial standard ranges, but loses reserves more quickly at higher temperatures. FKM is strong precisely where temperatures are permanently high or safety reserves are required.

In practice, a distinction should always be made between continuous temperature, peak temperature and temperature changes. Especially load changes, hot-cold cycles and the combination of temperature plus medium significantly accelerate the ageing of many seals.

Typical areas of use in practice

Typical applications for EPDM

EPDM is particularly useful for:

• Seals in outdoor areas
• Water-carrying systems
• Window, door and façade seals
• Ventilation and air-conditioning systems
• Applications with ozone and UV exposure

Anyone looking for precisely fitting cut pieces or material solutions in these areas will find additional information on rubber sheets and on custom rubber seals.

Typical applications for NBR

NBR is particularly well suited to:

• Hydraulics and pneumatics
• Machines and systems with lubricants
• Oil- and fuel-carrying components
• Pumps, compressors and technical units
• Standard applications in mechanical engineering

Especially in technically oriented applications with contact to oil media, NBR is often the most cost-effective standard material.

Typical applications for FKM

FKM is preferably used for:

• High-temperature applications
• Chemically exposed process environments
• Fuel and oil exposure at a high level
• Systems with long maintenance intervals
• Applications with high requirements for service life and process reliability

Where replacement is complex or failure is expensive, the consideration usually shifts away from material price and towards total operating costs.

Advantages and disadvantages at a glance

Material	Advantages	Limits
EPDM	very strong weather, ozone and UV resistancevery good for water and many polar mediasuitable for outdoor applicationscost-effective for many standard cases	unsuitable for many oils, fuels and mineral-oil-based medialimited under certain chemical and thermal loads
NBR	very good oil and fuel resistancegood mechanical propertiescost-effective and widely usablestrong standard material for technical applications	weaker with ozone, UV and weatherthermally positioned below FKM
FKM	high temperature resistancevery good resistance to many aggressive mediahigh ageing resistanceuitable for demanding industrial applications	higher price levelfrequently oversized for simple standard applications

Quick selection by application

Application	Recommendation
Water, weather, outdoor area	EPDM
Oil, grease, hydraulics	NBR
Fuel, high temperatures	FKM
Chemically aggressive media	FKM
Standard mechanical engineering	NBR

Master comparison: all decisive criteria at a glance

Criterion	EPDM	NBR	FKM
Water resistance	very high	low	good
Oil / fuel resistance	weak	very high	very high
UV / ozone	very high	weak	good
Temperature	up to approx. 120 °C	up to approx. 100 °C	up to approx. 200 °C
Chemicals	good (polar)	medium	very high
Service life	high outdoors/water	high with oil	very high under extreme conditions
Costs	low	low	high

Costs vs. service life

A common practical mistake lies in looking purely at the material price.

• NBR: cheaper purchase, more frequent changes possible
• EPDM: cost-effective with suitable media, long service life outdoors
• FKM: high price, but significantly longer service lives and less downtime

The most cost-effective solution almost always results from the total operating cost consideration, not from the unit price.

Typical practical cases

• EPDM in an oil-based environment → swelling, material failure after a short time
• NBR outdoors → embrittlement due to UV and ozone
• FKM in a standard application → technically suitable, economically oversized

These cases show that the wrong material choice rarely stands out immediately, but causes considerable problems in the long term.

Selection aid: which material fits when?

Anyone wishing to go deeper into individual materials will find additional information on EPDM seals, NBR seals, FKM seals and in the guide.

The best seal is rarely the one with the highest performance value on paper. The best seal is the one that fits the medium, the temperature, the environment and the expected service life.

If water, weather, UV and ozone are the focus, EPDM is usually the first choice. If oil, grease, hydraulic media or fuels are relevant, NBR is ahead in many cases. If high temperatures, aggressive media or long service lives under difficult conditions are required, the path often leads to FKM.

A common mistake is to look at only a single advantage. A material can, for example, be chemically suitable but offer too little mechanical or thermal reserve. Likewise, a cheap material at the purchasing stage can be the most expensive solution in the long term if downtime or early changes occur.

Standards and requirements in practice

In many applications, standards and approvals also play a role. These include, among others:

• FDA conformity for food areas
• KTW and DVGW for drinking water applications
• DIN and ISO standards for technical seals

These requirements significantly influence the material choice and should be taken into account at an early stage.

Common mistakes in material selection

In practice, the same mistakes occur again and again:

1. The medium is described too generally, although additives, cleaning chemicals or mixed media are relevant.
2. Only room temperature is considered, but not the actual operating temperature in the process.
3. Outdoor applications are planned with NBR, although UV and ozone exposure act permanently.
4. Highly loaded applications are designed with standard materials, although FKM would be more cost-effective.
5. The seal is selected only by price, instead of by service life and failure costs.

Especially for series applications, special contours or demanding operating conditions, it is therefore worth coordinating material, Shore hardness, geometry and manufacturing process.

Avoid installation and practical mistakes

In addition to material selection, installation and design also significantly influence service life:

• wrong Shore hardness leads to leaks or premature wear
• excessive preload unnecessarily stresses the seal
• incorrect storage impairs material properties
• unsuitable geometry reduces the sealing effect

These factors have a direct effect on service life and process reliability.

In conclusion

EPDM, NBR and FKM each have a clear place in practice. EPDM is strong with water, weather and outdoor applications. NBR is the resilient standard for oil and fuel contact. FKM is the solution for high temperatures, chemical exposure and demanding operating conditions. Anyone who properly matches this basic logic with the real application will make the right material decision more quickly and significantly reduce later failures.

Request a suitable seal now or have material checked:

• individual advice for your application
• selection of the optimum material
• dimensionally accurate production to drawing

Start your enquiry directly via the page for rubber seals or submit your requirements.

For specific requirements for cut pieces, series production or material-appropriate selection, the pages EPDM seal, NBR seal, FKM seal and rubber seals are also useful.

Frequently asked questions

Which material is better: EPDM, NBR or FKM?

That depends on the application. EPDM is very well suited to water, weather, ozone and outdoor areas. NBR is strong with oil, grease, hydraulics and many mechanical engineering applications. FKM is the suitable choice for high temperatures, aggressive media and long service lives.

When should EPDM be used instead of NBR or FKM?

EPDM is particularly well suited to water applications, outdoor areas, window and façade seals, ventilation systems and applications with UV, ozone and weather exposure.

For which applications is NBR the right choice?

NBR is suitable above all for oil- and fuel-containing environments, hydraulics, pneumatics, pumps, compressors and many classic applications in mechanical engineering.

When is FKM worth it?

FKM is worth it at high temperatures, chemically exposed processes, demanding industrial applications and wherever long service lives and high process reliability are required.

Is FKM the same as Viton?

Viton is a well-known trade name in the FKM environment. Anyone searching for Viton usually means FKM seals in practice.

Which seal is suitable for oil and fuel?

For many applications with oil, grease, hydraulic media and fuels, NBR is a very good standard solution. At higher temperatures or with additional chemical exposure, FKM is often the better choice.

Which seal is suitable for water and outdoor areas?

For water, moisture, weather, ozone and UV radiation, EPDM is the suitable material in many cases.

Why is looking purely at price problematic with seals?

A cheap material at the purchasing stage can ultimately cause significantly higher total costs through more frequent changes, downtime or failures. The entire service life should therefore always be considered.

Which mistakes occur particularly frequently in material selection?

Typical mistakes are too rough a description of the medium, ignoring the real operating temperature, the use of NBR outdoors or selection solely by price instead of by service life and load.

Do standards and approvals play a role in material selection?

Yes. Depending on the field of use, approvals and requirements such as FDA, KTW, DVGW as well as technical DIN and ISO specifications can be relevant and influence the material selection.

Our rubber sheets

For industry and trade we offer a wide variety of rubber sheets.

SBR rubber sheet

Our high-quality SBR rubber sheet (styrene-butadiene rubber) is the solution for numerous industrial and commercial applications. This rubber sheet is manufactured from first-class styrene-butadiene rubber and stands out thanks to its outstanding physical properties.

EPDM rubber sheet

Discover the versatility and reliability of our EPDM rubber sheet, which is manufactured from ethylene propylene diene monomer (EPDM). This high-quality elastomer solution has been specially developed to meet the most demanding industrial and commercial applications.

NBR rubber sheet

The NBR rubber sheet is a high-quality industrial product that has been specially developed for applications where excellent resistance to oils, greases and various chemicals is required.

Viton rubber sheet

The Viton rubber sheet is a high-quality technical product that is used for a wide range of industrial applications. Manufactured from fluoro rubber (FKM), it offers outstanding properties that make it the ideal choice for extreme conditions.

FKM rubber sheet

The FKM rubber sheet is a high-quality technical product that is ideal for use in demanding industrial applications. Made from fluoro rubber (FKM), it stands out thanks to a wide range of outstanding properties that make it the optimum choice for extreme operating conditions.

Silicone rubber sheet

The silicone rubber sheet is a first-class technical product that has been specially developed for applications that place high demands on temperature resistance and flexibility.

PUR rubber sheet

The PUR rubber sheet, manufactured from high-quality polyurethane, is a technically advanced product that has been developed for applications that place the highest demands on abrasion resistance and mechanical resilience.

Neoprene rubber sheet

The neoprene rubber sheet, manufactured from high-quality chloroprene rubber (CR), is a versatile technical product that is ideal for a wide range of industrial and commercial applications.