EN ISO 5359 Low-Pressure Flexible Connection Assemblies (Hose Assemblies) for Use with Medical Gas Systems

EN ISO 5359, Low-pressure flexible connecting assemblies (hose assemblies) for use with medical gas systems, which originated as a European standard and was subsequently published by the International Organization for Standardization (ISO), specifies the specific requirements for high-pressure assemblies for use with conventional gas supply systems for medical applications. This standard includes purchasing instructions for the design, manufacture, specification, and testing of hose assemblies used to deliver the medical gases listed in the table provided in the standard.

The hose assemblies with connectors defined in this standard and shown in the figure are intended for use in the following situations:

• Between a pipeline terminal unit and medical equipment
• Between the fixed pipeline system and the terminal unit of the system where the user performs connection and disconnection operations
• Between a terminal unit at the end of the fixed pipeline system and a second terminal unit or quick-connect socket
• For connection between an emergency source and a fixed pipeline system
• For connection between a medical gas pressure regulator and medical equipment

Some types of equipment include internally mounted hose assemblies that cannot be removed by the user or serviced without disassembling the equipment. For example, overhead rails and some hinged arm booms. These are outside the scope of this standard. Additionally, this standard does not include electrical conductivity requirements.

For the purposes of this standard, the following definitions apply:

• Low-pressure flexible connector assembly (hose assembly): An assembly consisting of a hose with permanently attached gas-specific supply and equipment connectors and designed for delivery of medical gases at pressures between 300 kPa and 1400 kPa and for use with vacuum service at pressures between 40 kPa and 90 kPa below atmospheric pressure.
• Supply connector: A gas-specific part of a hose assembly that allows it to be connected to a gas source.
• Equipment connector: A gas-specific part of a tubing assembly that connects to medical equipment, terminal units, or a fixed pipette.
• Medical gas: Any gas or gas mixture intended to be administered to patients for therapeutic, diagnostic or prophylactic purposes or for surgical instrumentation.
• Medical gas supply system: Refers to either:
  • A non-flammable medical gas pipeline system that includes a central supply system, control equipment, a pipeline distribution system, and terminal units at which non-flammable medical gases or vacuum can be regulated.
  • Any other installation that does not have a permanent pipeline system but uses a medical gas supply source complete with pressure regulators.
• Terminal unit: The outlet device (vacuum inlet) in the medical gas supply system through which the user performs connection and disconnection operations.
• Tubing fitting: It is the part of a connector that is pushed into the hole (lumen) of the tubing and fixed.
• Quick coupler: A pair of threaded, gas-specific components that can be easily and quickly assembled with one or both hands, without the use of tools. This typically consists of a probe and a socket with a control valve.
• Diameter index safety system connector: A range of male and female components intended to maintain gas specificity by allocating a seam of different diameters to the mating connectors for each gas.
• Non-interchangeable screw connector: A range of male and female components intended to maintain gas specificity by allocating a set of different diameters and left or right hand threads to the mating connectors for each specific gas.
• Hose fitting check valve: A valve that is normally closed and allows flow in both directions when opened by insertion of a suitable gas-specific connector.
• Gas specific: Having features that prevent interchangeability, thus allowing assignment to only one gas or vacuum service.
• Maximum working pressure: The maximum pressure at which the hose assembly is intended to be used.

All components and hose assemblies must be supplied clean and free of oil, grease and particulate matter. Precautions must be taken to maintain cleanliness during transport and storage.

Any cleaning and degreasing method that automatically removes all surface dirt and hydrocarbons and leaves no residue of its own can be used. Chemical cleaning methods typically require a bottom wash and drying process to remove residue.

Recommendations for materials used in the construction of general assemblies are included in the annex of the standard.

When testing hoses and hose assemblies to assess compliance with the requirements of this standard, the following rules should be used when performing tests:

• The test environment must be medical air
• All tests must be carried out at a temperature of 23 degrees plus/minus 2 degrees.

The requirements specified in this standard for hoses must be met for each batch of hose supplied, using at least one different sample for each test. When used or stored in rooms with varying temperatures, care must be taken to ensure that the hose has sufficient time to reach the required ambient temperature. Hose assembly users should be aware that certain materials soften at temperatures exceeding 25°C, increasing the likelihood of the hose kinking, deformation, and clogging.

The inner diameter of the hoses must comply with ISO 1307. The nominal inner diameter of the hose must be adjusted to meet national requirements for pressure drop and medical gas flow. Vacuum hoses must have a minimum inner diameter of 6,3 mm.

When tested in accordance with this standard, the minimum burst pressure of hose used in all services other than vacuum, in accordance with ISO 1402, shall be 5000 kPa (50 bar) or four times the design working pressure, whichever is greater.

When tested in accordance with this standard, the hose shall comply with the following requirement: when the pressure is increased from 50 kPa to 1400 kPa, the increase in outside diameter shall not exceed 5 percent of the original diameter.

Unsupported and unpressurized hose must be capable of being shaped to an inside radius of ten times the inside diameter of the hose without visible kinks.

When tested for flexibility in accordance with this standard, the reduction in flow shall not exceed 10 percent and the hose shall not show visible deformation.

When tested as described in the ISO 8033 standard, the adhesion strength should be at least 1,6 kN/m.

When tested using a test pressure of 1400 kPa, as described in the ISO 1402 standard, the change in length at the test pressure should not exceed plus/minus 5 percent.

Our organization, which has been supporting businesses across all sectors for years through a wide range of testing, measurement, analysis, and evaluation activities, has a strong team of employees who closely follow global developments in science and technology and are constantly improving themselves. In this context, we also provide testing services in accordance with the EN ISO 5359 standard for "Low-pressure flexible connection assemblies (hose assemblies) for use with medical gas systems."