ISO/DIS 16010

ISO/TC 45/SC 4

Secretariat: DSM

Date: 2025-11-21

Elastomeric seals — Material requirements for seals used in pipes and fittings carrying gaseous fuels and hydrocarbon fluids

Garnitures d'étanchéité en élastomères — Exigences matérielles pour les joints utilisés dans les canalisations et les raccords véhiculant des combustibles gazeux et des hydrocarbures liquides

DIS stage

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Contents

Foreword

Scope

Normative references

Terms and definitions

Classification

Requirements

Materials

Finished-seal requirements

Test pieces and temperature

Preparation of test pieces

Test temperature

Quality assurance

Storage

Designation

Marking and labelling

(normative) Materials in contact with dimethylether

(normative) Materials in contact with hydrogen

(informative) Quality assurance

(informative) Guidance on storage of seals

Bibliography

Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents).

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This document was prepared by Technical Committee ISO/TC 45, Rubber and rubber products, Subcommittee SC 4, Products other than hoses.

This third edition cancels and replaces the second edition (ISO 16010:2019), which has been technically revised.

The main changes compared to the previous edition are as follows:

• normative references have been updated to the latest version;
• requirements and test methods for the use with dimethylether (DME) are added;
• classes and test methods for the use with hydrogen gas are added.

NOTE It is remarked that dimethylether can add to the energy transition because it is possible to make it from renewable sources. It such cases it is often listed as (r)DME.

Any feedback or questions on this document should be directed to the user’s national standards body. A complete listing of these bodies can be found at www.iso.org/members.html.

Elastomeric seals — Material requirements for seals used in pipes and fittings carrying gaseous fuels and hydrocarbon fluids

This document specifies requirements for elastomeric materials used in seals for supply pipes and fittings, ancillaries and valves at operating temperatures in general from –5 °C up to 50 °C and in special cases from –15 °C up to 50 °C, for the following:

1. general applications (see Table 4, type G series):
2. gaseous fuel [manufactured, natural, liquefied petroleum gas (LPG), dimethylether (DME) and hydrogen in the gaseous phase],
3. hydrocarbon fluids with an aromatic content up to 30 % (by volume), including LPG and DME in the liquid phase;
4. special applications (see , type H):
5. b)—materials suitable for carrying gaseous fuels containing gas condensates and hydrocarbon fluids of unrestricted aromatic content.

General requirements for finished joint seals are also given; any additional requirements called for by the particular application are specified in the relevant product standards, taking into account that the performance of pipe joints is a function of the seal material properties, seal geometry and pipe joint design. This document is used where appropriate with product standards which specify performance requirements for joints.

This document is applicable to joint seals for all pipeline materials, including iron, steel, copper and plastics.

In the case of composite sealing rings, the requirements in 5.2.8 and 5.2.9 apply only when the materials used for any elastomeric parts come into contact with gaseous fuel or hydrocarbon fluid.

Elongation at break, tensile strength, compression set and stress relaxation requirements for materials of hardness classes 80 and 90 apply only when they constitute that part of the seal which participates directly in the sealing function or contributes directly to long-term stability.

This document is not applicable to the following:

• seals made from cellular materials;
• seals with enclosed voids as part of their design;
• seals required to be resistant to flame or to thermal stress;
• seals which contain splices joining pre-vulcanized profile ends.

The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

ISO 188:2023, Rubber, vulcanized or thermoplastic — Accelerated ageing and heat resistance tests

ISO 2859-1, Sampling procedures for inspection by attributes — Part 1: Sampling schemes indexed by acceptance quality limit (AQL) for lot-by-lot inspection

ISO 3384-1:2024, Rubber, vulcanized or thermoplastic — Determination of stress relaxation in compression — Part 1: Testing at constant temperature

ISO 3951-1, Sampling procedures for inspection by variables — Part 1: Specification for single sampling plans indexed by acceptance quality limit (AQL) for lot-by-lot inspection for a single quality characteristic and a single AQL

ISO 15105-1:2007, Plastics — Film and sheeting — Determination of gas-transmission rate — Part 1: Differential-pressure methods

ISO 37, Rubber, vulcanized or thermoplastic — Determination of tensile stress-strain properties

ISO 48-2, Rubber, vulcanized or thermoplastic — Determination of hardness — Part 2: Hardness between 10 IRHD and 100 IRHD

ISO 815-1, Rubber, vulcanized or thermoplastic — Determination of compression set — Part 1: At ambient or elevated temperatures

ISO 815-2, Rubber, vulcanized or thermoplastic — Determination of compression set — Part 2: At low temperatures

ISO 1431-1, Rubber, vulcanized or thermoplastic — Resistance to ozone cracking — Part 1: Static and dynamic strain testing

ISO 1817, Rubber, vulcanized or thermoplastic — Determination of the effect of liquids

ISO 3302-1, Rubber — Tolerances for products — Part 1: Dimensional tolerances

ISO 9691:1992, Rubber — Recommendations for the workmanship of pipe joint rings — Description and classification of imperfections

ISO 23529, Rubber — General procedures for preparing and conditioning test pieces for physical test methods

No terms and definitions are listed in this document.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

• ISO Online browsing platform: available at https://www.iso.org/obp
• IEC Electropedia: available at http://www.electropedia.org/

Five classes of material for pipe seals are specified in Table 2 and Table 3.

A nominal hardness shall be specified within the ranges in Table 1.

Table 1 — Hardness classification

The materials shall be free of any substances which may have a deleterious effect on the life of the seals, or on the pipe or fittings.

Tolerances shall be specified from the appropriate classes in ISO 3302-1.

The seals shall be free of defects or irregularities which could affect their function. Classification of imperfections shall be in accordance with ISO 9691:1992, as follows:

• surface imperfections in zones involved in the sealing function as described in 4.1.1 of ISO 9691:1992 shall be considered as defects;
• minor surface imperfections in zones not involved in the sealing function as described in 4.1.2.1 b) of ISO 9691:1992 shall not be considered as defects.

Major surface imperfections in zones not involved in the sealing function as described in 4.1.2.1 a) of ISO 9691:1992 can be considered as defects. This shall be agreed between the interested parties; the acceptance criteria will depend upon the seal type or design.

Internal imperfections as described in 4.2 of ISO 9691:1992 could be considered as defects. The compressive force can be determined in accordance with ISO 7743. The acceptable limiting values of the compressive force shall be agreed between the interested parties; they will depend upon the seal type or design.

When determined by the micro-test specified in ISO 48-2, the hardness shall comply with the requirements given in Table 2 or Table 3.

NOTE If the dimensions of a seal are appropriate, the normal test method specified in ISO 48-2 can be used, provided that the micro-test method is used for referee purposes.

For the same seal, the difference between the minimum and maximum hardness values shall not be more than 4 IRHD. Each value shall be within the specified tolerances.

Tensile strength and elongation at break shall be determined by the method specified in ISO 37. Dumb-bell shaped test pieces of type 1, 2, 3 or 4 shall be used. Type 2 is the preferred type. The test report shall state the dumb-bell type whenever type 2 is not used.

The tensile strength and the elongation at break shall comply with the requirements given in Table 2 or Table 3.

General

If the test piece is taken from a seal, then the measurement shall be carried out as far as possible in the direction of compression of the seal in service.

Compression set at 23 °C and 70 °C

When determined by the method specified in ISO 815-1, at 23 °C and 70 °C using the small type B test piece, the compression set shall comply with the requirements given in Table 2 or Table 3.

If the cross-section of a seal is too small to obtain suitable test pieces, a type B test piece can be prepared either by cutting from a test slab or by moulding a disc (see 5.1).

Low-temperature compression set at –5 °C

When determined by the method specified in ISO 815-2using the small type B test piece and a recovery time of (30 ± 3) min, the compression set after 72 h at –5 °C, when measured at –5 °C, shall comply with the requirements given in Table 2 or Table 3.

Test pieces prepared for the determination of hardness (see 5.2.3) and for the determination of tensile strength and elongation at break (see 5.2.4) shall be aged in air at 70 °C for 7 days by the normal oven method specified in ISO 188:2023 (method A).

The changes in hardness, tensile strength and elongation at break shall comply with the requirements given in Table 2 or Table 3.

The stress relaxation shall be determined by method A of ISO 3384-1:2024, after applying mechanical and thermal conditioning. Measurements shall be taken after 3 h, 1 day, 3 days and 7 days for the 7-day test and after 3 h, 1 day, 3 days, 7 days, 30 days and 90 days for the 90-day test. The best-fit straight line shall be determined by regression analysis using a logarithmic time scale, and the correlation coefficients derived from this analysis shall not be lower than 0,93 for the 7-day test and 0,83 for the 90-day test. The 7-day and 90-day requirements in Table 2 and Table 3 are those derived from these straight lines.

For continuous measurement using an apparatus as described in ISO 3384-1:2024, the 7-day and 90‑day requirements in Table 2 and Table 3 are those derived from the measurements at 7 days and 90 days.

The stress relaxation in compression shall comply with the requirements given in Table 2 or Table 3 at the following temperatures and times:

• 7 days at (23 ± 2) °C;
• 90 days at (23 ± 2) °C.

The test temperature shall be maintained within the specified tolerance during the whole period of the test and verified by suitable recording equipment on a continuous basis.

The 90-day test shall be considered as a type approval test.

If the test piece is taken from a seal, then the measurement shall be carried out as far as possible in the direction of compression of the seal in service.

When determined by the method specified in ISO 1817, the volume change after 7 days immersion at 23 °C in liquid B and, in addition, followed by drying in air for 4 days at 70 °C, shall comply with the requirements given in Table 2 or Table 3.

When determined by the method specified in ISO 1817, after 7 days immersion at 70 °C in standard oil No. 3, the volume change shall comply with the requirements given in Table 2 or Table 3.

Materials intended to be used in contact with DME shall, when determined by the methods specified in Annex A, comply with the requirements given in Table A.1 or Table A.2 of Annex A.

The test piece shall comply with the requirements given in Table 2 or Table 3, when determined by the method specified in ISO 1431-1, under the conditions set out below:

Sealing elements which are protected by packaging, whether packaged separately or not, up to the time of installation shall meet the same requirement but using an ozone concentration of (25 ± 5) pphm.

When determined by the method specified in ISO 815-2 using the small type B test piece and a recovery time of (30 ± 3) min, the compression set of elastomeric materials which are intended to be used at temperatures below –5 °C and down to –15 °C shall after 72 h at –15 °C, when measured at –15 °C, comply with the requirements given in Table 2.

Materials intended to be used in contact with hydrogen shall be designated one of the permeability classes listed in Table B.1, using the method described in Annex B.

Unless otherwise specified, test pieces shall be cut from the finished product by the method specified in ISO 23529. If satisfactory test pieces cannot be prepared in accordance with the instructions given for the appropriate test method, they shall be taken from test slabs or sheets of suitable dimensions or shall be moulded in a suitable cavity. They shall be made from the same batch of the elastomer mix as used to make the seals and moulded under conditions which are comparable with those used in production.

For tests in which different sizes of test piece are permissible, the same size of test piece shall be used for each batch and for any comparative purposes.

Unless otherwise specified, tests shall be carried out at a standard temperature in accordance with ISO 23529.

Two standard laboratory temperatures are given in ISO 23529, but the recommended test temperature (if not already specified) in this document is 23 °C.

Table 2 — Requirements for materials used for seals suitable for carrying gaseous fuel and hydrocarbon fluids with an aromatic content of up to 30 % (by volume) (see Table 4, type G series)

Table 3 — Requirements for materials used for seals suitable for carrying gaseous fuels containing gas condensates and hydrocarbon fluids of unrestricted aromatic content (see Table 4, type H)

Quality assurance testing is not an integral part of this document, but guidance can be obtained from Annex C, which recommends appropriate test frequencies, product control tests and sampling techniques.

Quality assurance should preferably be in accordance with a standard such as ISO 9001 or equivalent.

See Annex D.

Elastomeric seals for pipelines, fittings, ancillaries and valves are designated according to their intended application as described in Table 4. The following information shall be used for a full designation of the seals:

EXAMPLE SEAL/ISO 16010/DN 150/GB/NBR/Tradename

Table 4 — Designation of elastomeric seals by type, application and operating temperature

Each seal, or parcel of seals where the marking of individual seals is not practicable, shall be marked clearly and durably, as listed below, such that the sealing capability is not impaired.

1. the manufacturer's identification;
2. the number of this document followed by the seal type and the hardness class, e.g. ISO 16010/GB/60;
3. the nominal size;
4. the quarter and year of manufacture, e.g. 3Q05;
5. the abbreviation for the rubber, e.g. NBR;
6. in the case of a product made out of a material resistant to a lower concentration of ozone (see 5.2.11), this shall be clearly indicated on the packaging.

EXAMPLE MAN/ISO 16010/GB/60/DN 150/3Q05/NBR

1. 
   (normative)
   
   Materials in contact with dimethylether
   1. General

Rubber materials used in gas installations, gas equipment and gas appliances that are intended to be used in contact with dimethylether (DME) or blends of DME and LPG shall fullfill the requirements in Clauses 4 to 10 and the requirements in this Annex. In this Annex two methods are given:

• method using liquids for testing (A.2.1): This methods makes testing easier and better repeatable and will be sufficient in most cases. The liquids used are proven to give a good indication what will happen during use with (liquefied) gases.
• method using liquefied gases for testing (A.2.2): This method is difficult and can only be performed in specialist laboratories. Because the real gases are used the result is closer to what really will happen during use.
  1. Requirements
     1. Using liquids for testing

When tested in accordance with the methods detailed in A.3.1 circular test pieces having a diameter between 30 mm and 40 mm and a thickness of (2 ± 0,2) mm shall be used. The material shall comply with the requirements given in Table A.1.

Table A.1 — Requirements on the materials change in contact with DME volume when immersed into liquid and it's change in mass after drying

In case the change in volume is larger then 40 %, the test in A.2.2 can be used for further examination whether the material still can be used in contact with DME or not.

• • 1. Using liquefied gases for testing

When tested in accordance with the methods detailed in A.3.2 circular test pieces having a diameter between 30 mm and 40 mm and a thickness of (2 ± 0,2) mm shall be used. The material shall comply with the requirements given in Table A.2

Table A.2 — Requirements on the materials change in volume when immersed into liquefied gas and it's change in mass after drying

• 1. Test methods
     1. Using liquids for testing

Three test pieces shall be tested in accordance with ISO 1817, using the following conditions:

1. determine the initial mass and volume of the test pieces;
2. immerse for 72 h at (23 ± 2) °C in n-butyl-acetate and pentane having a composition as given in Table A.3;
3. after removal from the liquid, wipe dry rapidly and weigh immediately in air and in water;
4. determine the change in volume with reference to the initial volume of the test pieces;
5. dry the test specimens for a period of 96 h in a normal air oven at (70 ± 2) °C;
6. determine the change in mass with reference to the initial mass of the test pieces.

Calculate the arithmetic mean values of the three results both after immersion and after drying.

Table A.3 — Composition of the liquid used for the test

• • 1. Using liquefied gases for testing

Three test pieces shall be tested in accordance with ISO 1817, using the following conditions:

1. determine the initial mass and volume of the test pieces
2. immerse for 72 h at (23 ± 2) °C in blend of DME and propane under pressure, such that it is assured the test pieces are totally immersed into the liquefied gas. The mixture of liquefied gases should have a composition as given in Table A.4;
3. after removal from the liquid, directly determine the change in volume using the photographic method.
4. determine the change in volume with reference to the initial volume of the test pieces;
5. dry the test specimens for a period of 96 h in a normal air oven at (40 ± 2) °C;
6. determine the change in mass with reference to the initial mass of the test pieces.

Calculate the arithmetic mean values of the three results both after immersion and after drying.

Table A.4 — Composition of the liquefied gas used for the test

1. 
   (normative)
   
   Materials in contact with hydrogen
   1. General

This annex describes the classes and tests to characterize elastomer materials for seals for the use with up to 100 % by volume hydrogen (H₂) with respect to permeation of hydrogen (H₂).

The method described in this annex leads to an additional material property regarding hydrogen (H2) permeability. This technical parameter can be used to compare different materials regarding the permeation of hydrogen (H₂). To support the selection of elastomer materials regarding their specific behaviour for hydrogen (H₂) applications a limit value for hydrogen (H₂) permeation is not specified but a classification is given. The technically relevant hydrogen (H₂) permeation on material samples with standardized dimensions is considered.

• 1. Requirements

The additional material property is determined without specifying a limit value. Based on the results gained in testing according to Clause A.3 materials shall be classified according to hydrogen permeability as given in Table B.1

Table B.1 — Hydrogen (H₂) permeability classes

• 1. Test methods
     1. General

Test pieces shall be cut from a sheet of material of (2 ± 0,2) mm.

The material shall be from the same compound formulation used to make the component, vulcanized under conditions which are comparable to those used in production.

Punch at least 2 test specimen from a slab with a thickness of (2 ± 0,2) mm.

NOTE The most common size is diameter 110 mm.

• • 1. Measurement of the thickness of the specimen

The thickness of the specimen shall be measured according to ISO 23529. Measure the thickness at minimum 10 measuring points spread all over the specimen. The deviation in between minimum and maximum shall be ≤ 0,2 mm.

• • 1. Preconditioning

The specimen shall be degassed at < 15 mbar_abs at (23 ± 5) °C for minimum 48 h.

• • 1. Assembly of specimen

Immediately after preconditioning install the specimen in the permeation test device according to ISO 15105-1:2007, Annex A (manometric method) and continue degassing of specimen in test device at < 15 mbar_abs at test temperature (23 ± 2) °C for minimum 5 h, vacuum on both sides applied.

• • 1. Measurement of the permeation rate

The test conditions shall be in accordance to ISO 15105-1:2007.

The measurement shall be carried out in accordance to Annex A (manometric method) of ISO 15105-1:2007.

To measure the permeation rate, set the gas flow rate at feed-side to minimum 50 cm³/min. The purity of the medium hydrogen H₂ shall be at least 99,9% by volume.

The pressure at the permeate-side shall be adjusted less than 15 mbar_abs.

The partial pressure difference shall be adjusted to (1 ± 0,1) bar.

NOTE 1 (1 atmosphere = 1,01325 bar)

The test volume shall be approximately 0,8 cm³.

NOTE 2 When using the typical specimen diameter of 110 mm, the surface area results in round about 78,4 cm².

The test shall be carried out at a temperature of (23 ± 2) °C. Additional permeation tests at deviating temperatures are possible.

• • 1. Determination of the gas transmission rate (GTR) and gas permeability (P)

The gas transmission rate (GTR) shall be determined according to ISO 15105-1:2007.

For reasons of practicability, the GTR shall be specified in the unit [cm³/ (m² (24 h) bar)].

The gas permeation (P) is determined by consideration of the specimen thickness d using Formula (B.1).

(B.1)

Accordingly, the gas permeability (P) as the relevant material parameter shall also be specified in the unit [cm³ mm/ (m² (24 h) bar)].

If the variation of the two specimen tested exceeds the limit of the corresponding permeability class, as given in Table B.2, two additional specimens shall be tested. In this case the overall mean permeability shall be calculated.

Table B.2 — Mean permeability and deviation

1. 
   (informative)
   
   Quality assurance
   1. Type tests

All tests, except those having a duration in excess of 28 days, should be carried out at least annually and whenever the manufacturing technique is changed significantly. Those tests having a duration in excess of 28 days should be repeated at five-year intervals. All tests, without exception, should also be carried out initially and whenever the elastomer formulation is changed significantly.

• 1. Product-control testing

The tests in accordance with 5.2.1 and 5.2.2 and the following tests in accordance with the methods listed in Table 2 should be carried out using test pieces in accordance with 5.1.

1. hardness;
2. tensile strength;
3. elongation at break;
4. compression set for 24 h at 70 °C.
   1. Sampling for product-control testing

The product-control tests should be carried out on lots of finished components using sampling procedures in accordance with

1. either ISO 2859-1 with a specified inspection level of, for instance, S2 and an AQL of, for instance, 2,5 % for attributes;
2. or ISO 3951-1 with a specified inspection level of, for instance, S3 and an AQL of, for instance, 2,5 % for variables.

These examples do not preclude the use by the manufacturer of more stringent combinations of inspection levels and AQL values from ISO 2859-1 or ISO 3951-1.

NOTE Having regard to the hazards associated with the transportation of flammable and explosive fluids, attention is particularly drawn to the need for stringent quality-control procedures.

1. 
   (informative)
   
   Guidance on storage of seals

At all stages between manufacture and use, the seals should be stored in accordance with the recommendations given in ISO 2230 .

The following points should be noted:

1. the storage temperature should be below 25 °C and preferably below 15 °C;
2. the seals should be protected from light, in particular strong sunlight and artificial light with a high ultraviolet content;
3. the seals should not be stored in a room with any equipment capable of generating ozone (e.g. mercury vapour lamps) or any high-voltage electrical equipment which may give rise to electric sparks or silent electrical discharges;
4. the seals should be stored in a relaxed condition free from tension, compression or other deformation (for instance, they should not be suspended from any part of the circumference);
5. the seals should be maintained in a clean condition.

Bibliography

[1] ISO 7743, Rubber, vulcanized or thermoplastic — Determination of compression stress-strain properties

[2] ISO 9001, Quality management systems — Requirements

[3] ISO 2230, Rubber products — Guidelines for storage