Medical Gases

Medical Gases, with their associated equipment, are widely used for treating patients.

Medical gases are classified as a medicine and, as such, within a medical environment they shall always be managed and controlled by an appropriately qualified healthcare professional. In a hospital this will be the Pharmacist. Information on managing medical gases by Pharmacists is provided by the Specialist Pharmacy Service.

Medical gases are administered by healthcare professionals in hospitals, clinics and care homes, by para-medics within the emergency services or are self-administered by the patient at home (having received appropriate training).

All medical gases and much of the associated equipment is regulated by UK legislation. UK and European legislation are generally aligned. The gases are classified as medicinal products for administration to a patient and the associated equipment is classified as a medical device when used to administer the gas. Some gases used for medical purposes can also be classified as medical device gases where they do not have a specific therapeutic outcome for the patient.

Medical gases, like other medicinal products, are required to have a Marketing Authorisation (product licence) in order to be sold. The Marketing Authorisation defines the quality specification, when a gas can be used and how it should be administered to a patient. For patient treatment, all medical gases must be supplied with an appropriate Marketing Authorisation.

Although medical gases are similar to non-medical gases, medical gases are not to be used for non-medical purposes. Equally, non-medical gases must not be used as a medical gas.

The UK Regulator for medical gases is the Medicines and Healthcare products Regulatory Agency (MHRA), who are an Executive Agency of the Department of Health and Social Care (DHSC).

The MHRA protects and promotes public health and patient safety by ensuring that medicines, healthcare products and medical equipment meet appropriate standards of safety, quality, performance and effectiveness, and are used safely.

Any organisation that wishes to manufacture medical gases must have a Manufacturer's Authorisation issued by the MHRA for the manufacture of medical gases. The organisation is required to operate a quality management system which complies with the basic principles and practices of Good Manufacturing Practice (GMP) for medicinal products and specifically for medical gases.

Any organisation that wishes to supply and / or distribute medical gases must have a Wholesale Dealer's Authorisation issued by the MHRA. The organisation is required to comply with the basic principles and practices of Good Distribution Practice (GDP). BCGA GN 32 was developed with the MHRA to ensure compliance with good distribution practice for medical gases.

Some equipment, such as medical gas regulators, demand valves and medical gas flow meters, that are associated with the administration of medical gases, are classified as medical devices. Medical devices must carry an appropriate certification mark. This can be either the UK CA mark or the European CE mark, this is a declaration by the manufacturer that the equipment complies with the relevant Medical Devices Regulations.        

Any organisation that wishes to manufacture medical devices (including medical gases classified as medical device gases) must conform to the requirements laid down in the relevant Medical Device Regulations and must be registered with the MHRA.

Every site where medical gases are routinely used must have a suitable storage area with appropriate security provision. All personnel required to handle, move or use medical gases must have received appropriate information, instruction, training and, as required, be under supervision. The appropriately qualified health care professional / Pharmacist must provide written policies and Standard Operating Procedures for the management and safe use of all aspects of medical gas supply and administration.

As with all medicines, medical gases have a defined shelf life which is specified within the relevant Marketing Authorisation. Where the medical gas is supplied in a gas cylinder it will have a label that will show the expiry date as well as the batch number of the medicinal product. Do not use medical gases once this shelf life has expired; upon expiry the gas cylinder should be returned back to the owner (normally the gas supplier).

Within medical facilities the primary method of supply for a medical gas is for it to be supplied into a bulk storage tank(s), from where it is delivered through a medical gas pipeline system (MGPS) into the facility. The MGPS can include vacuum systems, dental systems and dental air vacuum systems (DAVS). These MGPS have to be compliant with various standards, including those required by the Department of Health and Social Care (DHSC). Compliance is required, for example, with:

Health Technical Memorandum (HTM) 02 - Medical Gas Pipeline Systems

  1. Part A, Design, Installation, Validation and Verification.
  2. Part B. Operational Management

HTM - 2022 Supplements:

  1. Dental Compressed Air and Vacuum.

Copies are available here.

Within medical facilities an alternative method of supply is through the use of transportable medical gas cylinders. Where a MGPS is in use, gas cylinders are a secondary source of supply.
Some medical facilities may utilise on-site gas generation systems. Where these systems are in use they must meet the requirements for the manufacture of medical gases, including compliance with GMP and the site quality management system.  

Gas cylinder storage

Gas cylinders contain dangerous substances. Individual gases have hazardous properties and the gas is contained under pressure. Gas cylinders must always be stored and handled with care. When not in immediate use all gas cylinders must be kept:

  • in a designated store, being appropriately marked with safety signs and warning notices;
  • in a well ventilated store, away from any sources of ignition, excessive temperatures, flammable materials and from any incompatible products;
  • in a secure location where access is controlled;
  • under cover, in a clean condition suitable for use in a medical environment.

When choosing a cylinder for use, good stock management principles should be applied, for example, by selecting those with the shortest life remaining first, 'first-expired, first-out' (FEFO).

NOTE: Gas cylinders are attractive to thieves and are frequently stolen, both for the value of the materials they are made from and for their contents. This is particularly true of medical gases. Each store must incorporate appropriate security features and be included within the site security plan.

For more information, refer to BCGA CP 44, The storage of gas cylinders.

The use of medical gases

Only medical gases, which are connected to suitable medical devices, shall be used to administer medical gases to a patient.

Each person who administers a medical gas to a patient must be trained and be competent to administer the gas, as well as being trained and competent in the use of medical gas cylinders and their associated medical gas devices.

All personnel who store, handle or use medical gases shall be competent to do so, including being appropriately trained in manual handling, local security measures, general gases safety, as well as the safe management of any associated medical devices.

The gas suppliers will provide information on the safe and appropriate use of their medical products.

Equipment manufacturers / suppliers will provide information on the safe and appropriate use of their medical devices. This information will include ‘Instructions for use (IFU)'.

WARNING: Do not smoke or use naked flames close to gas containers or any areas where medical gases are in use. When oxygen is in use there is the potential for localised oxygen enrichment, leading to an increased risk of fire. Always carry out local risk assessment and implement suitable and sufficient controls, in particular for the management of electrical equipment. Refer to BCGA Leaflet 16.

Domiciliary use of medical gases

Medical oxygen is supplied to patients in their home, care home or other domiciliary facility.

Medical oxygen is provided by a Homecare Service Provider along with the associated therapy equipment. The medical oxygen may be supplied from cylinders, cryogenic containers or oxygen
concentrators. There is a range of associated therapy equipment available, including Continuous Positive Airway Pressure (CPAP) machines, dependant on the patient's needs. The Homecare Service Provider will work with the patient and, as appropriate, with those providing care for the patient, to install the oxygen equipment and to provide literature and training for safe management and use. Refer to BCGA GN 29, Medical gases. The management of medical oxygen in domiciliary use.

Cryogenic gases

Gases at cryogenic temperatures are used by and for the treatment of patients.

As examples, liquid nitrogen is used within cryotherapy to treat skin conditions and for some specialist medical procedures. Storage of oxygen as a liquid provides a bulk source which converts to a large quantity of gas, this can be beneficial for patients who are travelling or who require larger quantities for domiciliary use.

Cryogenic liquids are at extreme cold temperatures and require to be kept and used from specialist containers. All those handling and using cryogenic gases need specific training and competence.

For liquid nitrogen, refer to BCGA CP 30, The safe use of liquid nitrogen dewars.

For liquid oxygen, refer to BCGA GN 29, Medical gases. The management of medical oxygen in domiciliary use, and BCGA Leaflet 13, Medical gases. Medical oxygen in a vehicle.


Several BCGA member companies are licensed by the Regulatory Authorities to manufacture and distribute the medical gases used within the UK, they also provide a range of associated equipment and services. Within BCGA, all aspects of medical gases are managed by Technical Sub-Committee (TSC) 7.

The primary objective of BCGA TSC7 is to safeguard patients by ensuring that all products provided by BCGA member companies are safe to use and fit for their intended purpose. This is achieved by promoting safety, producing best practice guidance, liaising with the MHRA and other government departments and participating in relevant standards work.


  • BCGA CP 30 - The safe use of liquid nitrogen dewars
  • BCGA CP 36Cryogenic liquid storage at users' premises
  • BCGA CP 44 - The storage of gas cylinders.
  • BCGA GN 26 - Medical gases. Selection and maintenance of seals used on high pressure cylinders. 
  • BCGA GN 29Medical gases. The management of medical oxygen in domiciliary use.
  • BCGA GN 31 - Medical gases. The use of valves incorporating residual pressure devices.
  • BCGA GN 32 - Medical gases. Good distribution practice.
  • BCGA GN 37 - Medical gases. Data integrity
  • BCGA GN 39 - Medical Gases. Responsible person
  • BCGA GN 40 - Medical gases. Quality management systems. Corrective and preventative actions
  • BCGA GN 42 - Medical gases. Incident reporting
  • BCGA L 7 - The dangers of industrial gas abuse.
  • BCGA L 13 - Medical gases. Medical oxygen in a vehicle.
  • BCGA L 16 - The safe use of electronic cigarettes and other electronic devices used near medical oxygen.
  • BCGA TIS 6 - Gas cylinder identification. Label and colour coding requirements.
  • BCGA TIS 20 - Medical gases. BCGA policy on colour coding.
  • BCGA TIS 21 - Medical gases. BCGA policy on valve outlets.
  • BCGA TIS 36 - Medical gases. The safe handling and use of gas cylinders fitted with valves with integrated pressure regulators. 
  • BCGA TIS 37 - Medical gases. Gas cylinder cleanliness standards.
  • BCGA TIS 39 - Medical gases. Quality control and QP batch certification of bulk medical liquid oxygen.
  • BCGA TIS 42 - Medical gases. Data integrity policy

EIGA held an oxygen safety workshop in January 2012. The following presentations may be of interest:

  1. The safe use and prescription of medical oxygen.
  2. Oxygen fires in healthcare facilities.
  3. What oxygen safety means to a healthcare facility.

Medical gas service providers

Many BCGA member companies can provide services related to medical gases. See full list here.

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