CEN/TC 218

Date: 2024-07

prEN 16820:2024

Secretariat: BSI

Rubber and plastics hoses and hose assemblies for use in the pharmaceutical and biotechnological industry — Bonded elastomeric hoses with or without a lining

Gummi- und Kunststoffschläuche und -schlauchleitungen für den Einsatz in der pharmazeutischen und biotechnischen Industrie — Verbundene Schläuche aus Elastomeren mit oder ohne Innenschicht

Tuyaux et flexibles en caoutchouc et en plastique pour utilisation dans l'industrie pharmaceutique et biotechnologique — Tuyaux liés en élastomère avec ou sans tube intérieur

CCMC will prepare and attach the official title page.

Contents Page

European foreword 3

1 Scope 4

2 Normative references 4

3 Terms and definitions 5

4 Classifications and conditions of use 5

4.1 Hose types 5

4.2 Hose grades 7

5 Dimensions 8

5.1 Inside diameter, minimum thickness of the lining, bending radii 8

5.2 Concentricity 9

5.3 Length and tolerances for the hose assemblies 9

5.4 Minimum bending radius 9

6 Materials 9

7 Requirements and tests 11

7.1 Physical properties 11

7.2 Electrical properties 12

8 Designs/types of connection 13

9 Manufacturing of the hose assembly 14

10 Frequency of testing 14

11 Marking 15

11.1 Marking of the hoses 15

11.2 Marking of the fittings 15

11.3 Marking of the hose assemblies 15

12 Installation and user instructions 16

13 Storage and permissible storage time 16

Annex A (normative) Test procedure to determine the electrical resistance through the wall of hoses 17

Annex B (normative) Testing of crushing strength (only for hose type SD) 19

Annex C (normative) Behaviour to fire exposure 21

Annex D (normative) Surface roughness and design of hose couplings 23

Annex E (normative) Test frequencies for type tests and routine tests 24

Bibliography 25

European foreword

This document (prEN 16820:2024) has been prepared by Technical Committee CEN/TC 218 “Rubber and plastics hoses and hose assemblies”, the secretariat of which is held by BSI.

This document is currently submitted to the CEN Enquiry.

This document will supersede EN 16820:2017.

This document includes the following significant technical changes with respect to EN 16820:2017:

— In 4.1, Table 1 the term “design” has been changed to “type”;

— In 4.2, an error in the value for electrical volume resistance has been corrected;

— In 4.3 and 4.4 the term “design” has been changed to “type”;

— In Clause 6 the reference to EU Regulation 1935/2004 has been removed;

— In Clause 8, Figure 1 has been corrected;

This document applies to type D and type SD hose assemblies with hoses made of elastomers and bonded plastics for the transport of gaseous, vaporous, liquid or powdery substances in the pharmaceutical and the biotechnological industries. It specifies the classification, manufacturing and testing of as well as the materials, requirements and quality surveillance for hose assemblies.

These hose assemblies are intended to be used with the relevant substances at temperatures in the range from −30 °C to +100 °C, depending on the medium, and at operating pressures from −0,9 bar (vacuum) to 10 bar (see Table 2 and Table 3). For hoses with a lining made of PTFE and derivatives, temperatures from −30 °C to +140 °C are permissible.

Hose assemblies in accordance with this document are classified into four types, A – D, A – SD. B – D, B – SD.

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.

EN 1092‑1, Flanges and their joints — Circular flanges for pipes, valves, fittings and accessories, PN designated — Part 1: Steel flanges

EN 10204, Metallic products — Types of inspection documents

EN 10244‑2, Steel wire and wire products — Non-ferrous metallic coatings on steel wire — Part 2: Zinc or zinc alloy coatings

EN 10270‑1, Steel wire for mechanical springs — Part 1: Patented cold drawn unalloyed spring steel wire

EN 10270‑2, Steel wire for mechanical springs — Part 2: Oil hardened and tempered spring steel wire

EN 12115, Rubber and thermoplastics hoses and hose assemblies for liquid or gaseous chemicals — Specification

EN 12351, Industrial valves — Protective caps for valves with flanged connections

EN ISO 1402:2021, Rubber and plastics hoses and hose assemblies - Hydrostatic testing (ISO 1402:2021)

EN ISO 4671:2022, Rubber and plastics hoses and hose assemblies - Methods of measurement of the dimensions of hoses and the lengths of hose assemblies (ISO 4671:2022)

EN ISO 5817:2023, Welding - Fusion-welded joints in steel, nickel, titanium and their alloys (beam welding excluded) - Quality levels for imperfections (ISO 5817:2023)

EN ISO 7233:2021, Rubber and plastics hoses and hose assemblies - Determination of resistance to vacuum (ISO 7233:2021)

EN ISO 7326:2016, Rubber and plastics hoses - Assessment of ozone resistance under static conditions (ISO 7326:2016)

EN ISO 8031:2020, Rubber and plastics hoses and hose assemblies - Determination of electrical resistance and conductivity (ISO 8031:2020)

EN ISO 8033:2017, Rubber and plastics hoses - Determination of adhesion between components (ISO 8033:2016)

EN ISO 10619‑1:2018, Rubber and plastics hoses and tubing - Measurement of flexibility and stiffness - Part 1: Bending tests at ambient temperature (ISO 10619-1:2017)

EN ISO 10619‑2:2021, Rubber and plastics hoses and tubing - Measurement of flexibility and stiffness - Part 2: Bending tests at sub-ambient temperatures (ISO 10619-2:2021)

IEC/TS 60079‑32‑1:2018, Explosive atmospheres - Part 32-1: Electrostatic hazards, guidance

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

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

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

No terms and definitions are listed in this document.

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

— ISO Online browsing platform: available at https://www.iso.org/obp

— IEC Electropedia: available at https://www.electropedia.org/

Due to the operational requirements and the manufacturing conditions, the structural design of hose assemblies in accordance with this document can vary considerably. A selection of possible hose/hose assembly types is given in Table 1 and Table 2

Table 1 — Hose types^d

Table 2 —Hose assembly types^{d, e}

Hose assemblies in accordance with this document shall be autoclavable (vapour sterilization) for at least 30 min at 130 °C.

Pressures and temperatures other than those given in the scope can be agreed upon between the manufacturer and the user.

Hoses and hose assemblies for this application shall be classified into five grades:

— grade I: electrically insulated (no electrical bonding AND no static-dissipative layers);

— grade M: electrically bonded without static-dissipative lining or cover;

— grade Ω: electrically conductive;

— grade M/T: electrically bonded and with an electrical volume resistance through the hose wall not exceeding 10⁹ Ω;

— grade Ω/T: electrically conductive and with an electrical volume resistance through the hose wall not exceeding 10⁹ Ω.

Depending on the type, the following shall conform to the values in Table 2 and Table 3:

— the inside diameter of hoses;

— the minimum thickness of the lining;

— the minimum bending radius.

Table 3 — Dimensions and bending radii for hose type A – D / B – D

Table 4 — Dimensions and bending radii for hose type A – SD / B – SD

When determined in accordance with EN ISO 4671 on the basis of all readings of the dial gauge between the inside diameter and the surface of the cover, the concentricity shall be ≤ 1,0 mm for hoses with a nominal size ≤ 50 and ≤ 1,5 mm for hoses with a nominal size > 50.

The length of the hose assembly is considered to be the installation length measured between the sealing surfaces of the end fittings.

The permissible tolerance is mm for hose assemblies with a length of up to and including 1 000 mm.

The permissible tolerance is % for hose assemblies with a length of more than 1 000 mm.

The dimensions given in Table 2 and Table 3 apply to the minimum bending radius of type D and type SD hose assemblies.

Other dimensions will be agreed upon between the user and the manufacturer.

Table 5 lists the commonly used materials.

Table 5 — Materials

Verification of the fitting materials used for parts in contact with the product shall be by inspection documents, e.g. inspection certificate 3.1, in accordance with EN 10204.

The materials need to meet at least the requirements to use for the manufacture of hoses for the transport of gaseous, vaporous, liquid or powdery substances in the pharmaceutical and the biotechnological industries. Further requirements, e.g. in accordance with FDA, USP Class VI or EN ISO 10993‑5 may be agreed upon. Further requirements such as freedom of silicone and of substances of animal origin as well as TSE Compliance (TSE: Transmissible Spongiform. Encephalopathies) shall be agreed upon separately.

The physical properties of the materials used for the lining and cover shall conform to the values given in Table 6, when tested in accordance with the methods listed in Table 6. Tests shall be carried out either on samples taken from the hose or from separately vulcanized sheets (to the same degree as the hose).

The physical properties of the hose assemblies and the associated test methods are specified in Table 7

Table 6 — Physical properties of the lining and the cover

Table 7 — Physical properties of the hose assemblies

As a rule, a differentiation shall be made between electrically conductive and electrically non-conductive or insulating hose assemblies.

For certain applications, insulating hose assemblies are explicitly required. In such cases the electrical resistance, measured between the two hose fittings in accordance with EN ISO 8031:2020, shall not fall below 10⁹ Ω. Such hose assemblies shall be marked with the symbol “I”.

If electrical conductivity of the hose assemblies is required, this can be achieved by two methods:

1) Unless the hoses have a metallic supporting helix and/or (a) pressure carrier(s) designed as metallic braid in accordance with Table 1, two electrically bonding wires of low resistance shall be integrated into the hose design. The wires shall be mounted helically and guided such that they cross each other in regular intervals.

If fittings are mounted onto this hose, the connecting wires, helixes or braids shall be safely connected to the fittings.

When tested in accordance with EN ISO 8031:2020, the resistance shall not exceed 10² Ω over the whole length; the resistance being the one along the connecting wires, helixes or braids for hoses and the one between the fittings for hose assemblies. If electrical conductivity is achieved by this method, the hose shall be marked with the symbol “M”.

2) Integration of electrically dissipative materials into the hose design. If fittings are mounted onto this hose, a connection between the end fittings and the dissipative layer shall be provided for.

When tested in accordance with EN ISO 8031:2020, the resistance shall not exceed 10⁶ Ω over the whole length; the resistance being the one along the dissipative layer for hoses and the one between the fittings for hose assemblies. If electrical conductivity is achieved by this method, the hose shall be marked with the symbol “Ω”.

If hose assemblies in accordance with 1) or 2) are used in potentially explosive atmospheres, the volume resistance through the whole hose wall shall not exceed 10⁹ Ω. Further information is to be found in IEC/TS 60079‑32‑1:2018. In such cases, the hose shall additionally be marked with the symbol “T”, i.e. either “M/T” or “Ω/T”. Exceptions from the requirement for a limitation of the volume resistance valid for small outside hose diameters are listed in EN 12115.

The test method for the determination of the electrical volume resistance through the hose wall is given in Annex A (normative).

Both during and following the hydrostatic test in accordance with EN ISO 1402:2021, the electrical resistance from one end to the other shall be complied with for every hose and the electrical resistance from one end fitting to the next, for every hose assembly.

Electrical conductivity in Type SD shall not be obtained by only connecting the fittings to the helixes.

The following designs/types of connection are specified in this document:

— aseptic couplings;

— clamp couplings.

Other end fittings/couplings, such as flanges, shall be agreed upon between the user and the manufacturer.

The surface roughness and design of hose couplings for contact with the medium shall be specified in accordance with the hygiene classes given in Annex D.

Mounting shall be performed by means of, e.g. high-grade steel ferrules. Other types of assembly shall be agreed upon between the manufacturer and the user.

Hose side fitting transitions shall be designed with as small a gap as possible. The transitions between hose and fitting shall be conical and without beads (see Key 7 in Figure 1).

Any welds shall be made in accordance with EN ISO 5817:2023, quality level B (high), e.g. free of temper colours as well as free of burrs and gaps. Connection side fitting transitions shall be agreed upon between the manufacturer and the user. An example is given in Figure 1.

Key

Figure 1 — Example hose connection

The hose side assembly of the fittings for hoses of types D and SD shall be performed by means of ferrules. The responsibility for the assembly of the hose fittings into the hoses lies with the assembler/manufacturer of the hose assembly. Other types of assembly shall be agreed upon between the manufacturer and the user.

When using loose flanges, these shall be safeguarded against falling back; any element used for safeguarding shall be made of stainless materials.

Type testing and routine testing shall be as specified in Annex E.

Type tests are those tests required to confirm that a particular hose or hose assembly design manufactured by a particular method from particular materials meets all requirements of this document. The tests shall be repeated at a maximum of five-year intervals, or whenever a change in the method of manufacture or materials used occurs.

Routine tests are those tests required to be carried out on each length of finished hose or hose assembly prior to dispatch.

Hoses shall be clearly and durably marked by the manufacturer in an unambiguous and durable manner at intervals of not more than 1,0 m with at least the following information:

a) number of this document and the year of publication;

b) name or trade mark of the manufacturer;

c) hose type (A – D / A – SD / B – D or B – SD);

d) lining material;

e) inside diameter (in mm);

f) maximum working pressure, in bar, (MWP)/vacuum;

g) maximum working temperature range, e.g. −30 °C to +100 °C;

h) symbol for marking of the electrical properties, if relevant (e.g. Ω or Ω/T);

i) date of manufacture (quarter of the year/year);

j) batch number for traceability.

EXAMPLE EN 16820:2024— xxx — A–D —yyy — 19 — 10 bar — −30 °C/+100 °C — Ω — 2Q/2024 —zzz

Fittings shall be marked by the fitting manufacturer in an unambiguous and durable manner with at least the following information:

a) name or trade mark of the manufacturer;

b) material identification number;

c) batch number and hygienic class.

EXAMPLE xxx — X2CrNiMo17—12 —yyy — H3.

Hose assemblies are usually marked on the ferrules.

Data already given on the hose or the fitting is not required to be repeated, provided they correspond with the operational data, are clearly legible as well as unambiguous and durable.

The data of fitting and hose shall be adapted to one another.

Hose assemblies shall be marked by the manufacturer/assembler in an unambiguous and durable manner with at least the following information:

a) number of the standard;

b) name or trade mark of the assembler;

c) hose assembly type (A – D / A – SD / B – D or B – SD)

d) vacuum/maximum working pressure, in bar, (MWP);

e) date of assembly (month and year);

f) registration number (of the hose assembly).

EXAMPLE EN 16820 — xxx — A-D — 0,8/10 bar — 06–2024 — yyy

Deviating markings may be agreed upon between the manufacturer of the hose assembly and the user.

As far as the installation and application of the hose assembly is concerned, the manufacturers' information supplied together with the documentation shall be taken into consideration. In particular, the following information shall be borne in mind in any case:

— Hose assemblies shall be connected torsion-free; their movements within the installations shall not cause any torsional stress.

— Overbending (values lower than the smallest bending radius), external fretting, corrosion or damage shall be prevented by the appropriate positioning and guiding of the hose assembly. Such stresses can also be counteracted by additional protective designs, e.g. wire spiral wrap. Protective designs shall be agreed upon between the user and the manufacturer.

— Kinked hose assemblies shall no longer be used. Repairs may only be carried out by the manufacturer/assembler of the hose assembly.

— Hose assemblies shall be supplied closed and in their outer package, and the fittings shall be protected against damage.

— Hose assemblies shall be cleaned by the user prior to being commissioned.

Recommendations regarding the storage of hoses and hose assemblies are given in EN ISO 8331. The end of the hose shall be protected against damage and contamination during transport and storage.

The sealing surfaces of the hose fittings shall be protected against damage and contamination during transport and storage (e.g. with protective caps in accordance with EN 12351).

1. 
   (normative)
   
   Test procedure to determine the electrical resistance through the wall of hoses
   1. General

This test is usually carried out as a type test only. It is required by some hose product standards for hoses used in an explosive atmosphere. The test is carried out only when required by the hose product standard and only when hoses are specially ordered for use in an explosive atmosphere. It is not considered to be a standard or routine test.

• 1. Test procedure for hoses (without end fittings)
     1. Preparation for the test

Prepare the test pieces by cutting five lengths of hose approximately 300 mm long from samples taken at random from a production run.

Use an ohmmeter with a capacity of at least 10¹⁰ Ω and make the measurement at 500 V d.c.

The instrument shall be sufficiently accurate to determine the resistance between the lining and cover, measured through the hose wall. The measuring equipment shall be according to EN ISO 8031:2009, 4.2.1.4.

• • 1. Electrodes and contacts

For the outer electrode, see EN ISO 8031:2020, 4.2.2.1. For hoses with corrugated covers, a wetted conducting foam strip underneath the electrode is recommended to ensure good contact over the entire electrode surface.

For the use of conductive liquid or conductive silver lacquer or colloidal, see EN ISO 8031:2020, 4.2.2.1.

The inner electrode shall consist of tap water with an electrical conductivity of at least 10⁻⁴ S/m.

• • 1. Preparation and cleaning for test

See EN ISO 8031:2020, 4.3.

The surfaces of the test piece shall be clean. If necessary, they may be cleaned by rubbing with fuller's earth (magnesium aluminium silicate) and water, washing with distilled water and allowing to dry. Do not use organic materials which attack the material of the test piece or cause it to swell, and do not buff or abrade the test surface.

The surface of the test piece shall not become deformed either during the application of the contacts or during the test. Care shall be taken to ensure that the test piece is insulated from any electrical leakage path along its length.

• • 1. Conditioning

See EN ISO 8031:2020, 4.4.

• • 1. Test procedure

The test shall be carried out within 30 min with the test piece in the vertical position on blocks of polyethylene or another insulating material. First seal one end of the test piece with a plug of insulating material and mount the test piece vertically with the plugged end pointing down. Then fill the test piece with tap water (see EN ISO 8031:2020, 4.2.2.2) to a level 20 mm above the outer electrode. Check that there is no leakage.

Apply clean, reliable metal contacts to the outer electrode and the tap water inside. Then connect the ohmmeter to the inner and outer electrodes.

Apply the test voltage and measure the resistance (5 ± 1) s after application of the voltage.

Avoid breathing on the surfaces and thus creating condensation that could lead to inaccuracies. Also, avoid any conductive or semi-conductive connection between the individual hose layers at either end of the test piece.

Calculate the electrical resistance R, in ohms, through the hose by multiplying the measured electrical resistance R_m, in ohms by the conversion factor ID/25 (where ID is the inside hose diameter in millimetres):

(A.1)

NOTE ID/25 is a conversion factor for the standard square surface area.

1. 
   (normative)
   
   Testing of crushing strength (only for hose type SD)

One test specimen (hose) ≥ 350 mm long shall be placed onto a rigid, flat plate such that it is not under tension.

A square pressure plate with a thickness of 10 mm and a side length of 100 mm shall be placed centrally onto the test specimen. The distance d₁ between the two plates shall be measured (see Figure B.1).

The test force F (see Table B.1) shall be applied to the pressure plate for a duration of 3 min.

This can reduce the outside diameter of the hose by ≤ 15 %.

The test force shall be removed; after 5 min the distance d₂ between the two plates shall be measured again.

The reduction, in per cent, shall be calculated as follows:

(B.1)

Table B.1 — Test force

Dimensions in millimetres

Key

Figure B.1 — Set up for testing of crushing strength

1. 
   (normative)
   
   Behaviour to fire exposure
   1. Test specimen

Hose assembly with closed ends.

• 1. Test equipment

— Bunsen burner;

— stopwatch;

— fastening elements suitable for the hose assembly to be tested.

• 1. Test procedure

The hose test specimen shall be bent to form a U with a radius in accordance with Figure C.1.

The test specimen shall be filled with liquid F in accordance with ISO 1817.

The test specimen shall be subjected, for 3 min, to the flame of a Bunsen burner with a tube diameter of 10 mm, with the air supply to the burner being shut off.

The distance between the burner and the test specimen shall conform to Figure C.1.

The hose or hose assembly test specimen shall be considered to be non-flammable if:

— it stops burning after the removal of the Bunsen burner, or

— no points of glowing combustion are visible 2 min after the removal of the Bunsen burner.

Following the completion of the test, the test specimen shall be tight against leakage of the test liquid when subjected to a visual examination.

Dimensions in millimetres

Key

Figure C.1 — Set-up for testing the behaviour to fire exposure

1. 
   (normative)
   
   Surface roughness and design of hose couplings

For the surface roughness and design of hose couplings see Table D.1.

Table D.1 — Internal and external surface roughness

1. 
   (normative)
   
   Test frequencies for type tests and routine tests

The minimum frequency of test for type tests and routine tests shall be as specified in Table E.1.

Table E.1 — Test frequency of type tests and routine tests

Bibliography

[1] EN ISO 8331:2016, Rubber and plastics hoses and hose assemblies - Guidelines for selection, storage, use and maintenance (ISO 8331:2016)

[2] EN ISO 10993‑5:2009, Biological evaluation of medical devices - Part 5: Tests for in vitro cytotoxicity (ISO 10993-5:2009)

[3] EN 10088‑2, Stainless steels — Part 2: Technical delivery conditions for sheet/plate and strip of corrosion resisting steels for general purposes

[4] EN 10088‑3, Stainless steels — Part 3: Technical delivery conditions for semi-finished products, bars, rods, wire, sections and bright products of corrosion resistant steels for general purposes

[5] BS 3592‑1:1986, Steel wire for hose reinforcement — Specification for coated round and flat steel wire for rubber hose reinforcement