Medical gas cylinders are an essential part of modern healthcare.

Whether it’s gas cylinders for medical oxygen therapy to treat respiratory conditions, those used for anaesthesia and surgical use, or speciality gas cylinders for medical equipment calibration – medical gases are used across healthcare and homecare settings to treat millions of patients every day.

Learn more about medical gas cylinders and applications in our ultimate A to Z guide.

A – Ambulatory Oxygen

Ambulatory oxygen therapy refers to providing oxygen to a patient (often suffering from COPD) during exercise and everyday activities. Ambulatory oxygen systems need to be small and light enough to carry, while providing the capacity a patient needs when on the go. The best gas cylinders for ambulatory oxygen applications tend to be lightweight Type 3 carbon composite, with a high pressure (300 Bar).

B – Bar

Bar is a metric unit of pressure. 1 bar is equal to 100,000 pascal (pa) and is slightly less than the average atmospheric pressure on Earth at sea level (0.987 atmospheres). Typically, medical gas cylinders can be filled to pressures of 200 – 300 bar. All medical gas cylinders from AMS Carbon Composite Cylinders are available as high pressure (300 bar).

C – Carbon fibre

Carbon fibre (also known as CF and graphite fibre) is an advanced material made from small fibres of carbon (5 to 10 micron). Its properties include high tensile strength, high strength to weight ratio, high chemical resistance, high temperature tolerance and low expansion – making it ideal for applications that require high strength and durability and low weights.

Carbon fibre is combined with other materials, including resin and glass fibre to form the composite used in Type 2 and Type 3 gas cylinders.


Chronic Obstructive Pulmonary Disease (COPD) refers to a group of lung conditions that cause breathing difficulties. COPD is now the third biggest killer after heart disease and cancer. There is no cure, and the number of people dying from COPD is rising steadily – in 2016, the condition took the lives of more than 3 million people worldwide. COPD patients typically require oxygen therapy to manage their condition.


DOT refers to the U.S. Department of Transportation (DOT) safety standards for portable cylinders used to transport non-flammable, flammable, and poisonous materials. AMS Composite Cylinders produce cylinders to a range of global standards, including DOT – so they are approved for medical use in the USA.

E – Emergency Oxygen

Emergency oxygen therapy is administered to stabilise patients who are critically ill. The goal of emergency oxygen therapy is usually to reduce hypoxaemia and improve tissue perfusion to prevent or limit organ damage. Patients are usually given high concentration oxygen to maintain sats (oxygen saturation) of 90% or above until they reach hospital. Ambulances and paramedics carry lightweight, high pressure emergency oxygen cylinders as part of their standard loadouts.

F – Fibre (as in glass fibre and carbon fibre)

Glass fibre and carbon fibre (see C) are materials used as part of the composites found in both Type 2 and Type 3 cylinders – they are lighter than aluminium and steel, and serve to reduce the weights of the cylinders, while maintaining high levels of strength and durability.

G – (Medical) Gases

In addition to medical oxygen, there are a number of pure gases and blends in widespread use across healthcare and homecare applications. These include nitric oxide, nitrous oxide, carbon dioxide, medical air, medical helium and oxygen mixtures, and a range of specialist gases for medical equipment calibration. At AMS Composite Cylinders, we produce standard and customised solutions for a full range of medical gases.

H – Home Oxygen

Home oxygen is used by a growing number of patients worldwide – primarily for the treatment of respiratory diseases including COPD and asthma. Patients may use either oxygen concentrators or home oxygen cylinders for their oxygen therapy.

I – ISO 11119-2

ISO 11119-2 is the international standard covering gas cylinders — Design, construction and testing of refillable composite gas cylinders and tubes — Part 2: Fully wrapped fibre reinforced composite gas cylinders and tubes up to 450 l with load-sharing metal liners. Additional information about ISO 11119-2 can be found at

J – Just in Time

“Just in Time” (also known as Lean Manufacturing) is a production method used to reduce timescales, waste and response times for the delivery of products. At AMS Composite Cylinders, we manufacture using efficient Just In Time principles, making cylinders to order and delivering them to tight schedules.

K – Kilograms

(See also W – Weight) For portable, emergency and ambulatory medical oxygen applications, weight matters, and every KG saved translates into real practical benefits for medical professionals and patients in terms of increased capacity, improved portability, better range and greater independence.

L – Lightweight

(See also K – Kilograms) Type 3 carbon composite cylinders offer significant weight savings over Type 1 and Type 2 cylinders. They can be up to 50% lighter than traditional Type 1 aluminium gas cylinders. AMS ultra-lightweight medical gas cylinders are some of the lightest Type 3 cylinders available on the market today

M – Medical Equipment Calibration

Gas mixtures are used to calibrate a range of medical equipment and monitors, including anaesthesia monitors, blood gas instruments, pulmonary testing equipment, lab environmental monitors, and diagnosis equipment. AMS provides a full range of carbon composite speciality gas cylinders and disposable aluminium canisters for calibration gases.

N – Non-Limited Life

Traditionally, all refillable gas cylinders have been supplied with a defined maximum lifespan (usually 15 years for Type 3 cylinders). Cylinders produced to NLL (Non-Limited Life) specifications have no maximum lifespan. They require testing every 5 years, and as long as they pass, they can be used indefinitely.

O – Oxygen

Medical oxygen is an essential part of modern healthcare and medicine – used in healthcare and homecare settings for a huge range of applications. From anaesthetic, life support and resuscitation, to oxygen therapy for conditions including COPD, asthma, Covid-19, cyanosis, shock, haemorrhage, carbon monoxide poisoning, trauma and cardiac/respiratory arrest. Medical oxygen can be delivered in a number of different ways, including medical oxygen cylinders, concentrators and centralised liquid oxygen systems in hospitals.

P – Portable oxygen

Medical oxygen cylinders come in a wide range of sizes, from large 50kg cylinders used in hospital settings, down to small, portable units for home oxygen therapy use. Portable oxygen cylinders are ideal for out of home use.

Q – Quality

The quality of medical oxygen can be critical – especially for patients requiring high flow rates, where a higher level of purity or quality can be essential to their continuing care. The purity of oxygen derived from oxygen concentrators may be as low as 90% depending on the flow rate. Oxygen supplied from medical oxygen cylinders will never drop below 99.6% regardless of the flow rate.

The quality of AMS Composite Cylinders is of paramount importance. Production takes place in a ISO9001:2015 compliant environment and all cylinders are produced to international standards such as ISO11119.

R – Range

One of the biggest challenges facing patients who require medical oxygen therapy is ‘range anxiety’ – making sure they have enough oxygen with them to complete everyday tasks and activities outside the home. Small and lightweight Type 3 oxygen cylinders can hold several hours of oxygen, helping to facilitate a more independent life for patients.

S – Sats

Oxygen saturation, or “O2 sats,” indicates the amount of oxygen traveling through your body with your red blood cells. Normal oxygen saturation is usually between 95% and 100% for most healthy adults. If the oxygen level is below this, it can be an indicator of a respiratory illness or a lung problem. People with low oxygen levels may need oxygen therapy or emergency oxygen.

T – Type

There are four cylinder types available on the market today. Type 1 – all metal cylinders (usually aluminium or steel), Type 2 – made from aluminium, hoop wrapped with carbon fibre, Type 3 – a thin aluminium liner, fully wrapped with carbon composite, and Type 4 – carbon composite with a polymer liner.

You’ll find a full rundown of the different cylinder types, and choosing the right Type of cylinder for your medical gas requirements at



UN/ISO is a worldwide, harmonised regulation for compressed gas cylinders. In the EU, cylinders must be manufactured in a way that complies with the Transportable Pressure Equipment Directive (TPED). The Pi mark is marked on cylinders to show that it meets the requirements of the EU TPED.

V – Valve

Gas cylinder shells are open-ended. Valves are fitted to gas cylinders at the neck to contain gases within the cylinders, and to provide a port for the controlled filling and release of gas during use. The valve can accommodate and incorporate a range of other safety devices, regulators and gauges to enable the safe and effective use of gas cylinders in a range of medical applications.

V – Volume

Volume refers to the size/capacity of gas within the medical gas cylinder. Using a carbon composite lightweight cylinder filled to 300 Bar can provide significantly more oxygen than older technologies filled to 200 Bar.

W – Weight

For ambulatory patients and for the emergency services, the weight of an oxygen cylinder can be crucial in being able to maintain quality of life, or in the case of the emergency services, maintaining life itself. AMS Composite Cylinders are among the lightest available on the market.

X – X-rays

Chest X-rays can be used in the diagnosis of several respiratory conditions that may require oxygen therapy, including COPD, pneumonia and lung cancer.

Y – Years

(See also – Non Limited Life) In healthcare applications, medical gas cylinders can be either rated to a defined maximum lifespan (usually 15 years), or Non-Limited Life (NLL) of service. Non-Limited Life cylinders can be used indefinitely, as long as they pass periodic testing requirements. In real world use, AMS carbon composite cylinders certified for NLL can last 30 years or more.

Z – Zoom!

With state of the art manufacturing facilities and best in class supply chain, AMS Composite Cylinders are obsessed with providing the best possible customer service and your cylinders will be zoomed to your door!


Medical Oxygen Cylinders from AMS Composite Cylinders

At AMS Composite Cylinders, we specialise in supplying high quality medical gas cylinders and medical oxygen cylinders to customers around the world – with Type 1, Type 2 and Type 3 cylinders available in standard and custom sizes for a full range of healthcare and homecare applications.

Supplying clients across the UK, Europe, the Middle East and Latin America, the company produces cylinders to a wide range of recognised global standards, holding accreditations in all major markets worldwide.

AMS Composite Cylinders Manufactures to ISO and EN Standards (including ISO-11119-2, ISO 11119-1, EN 12245, EN 12257, ISO 7666, and ISO 11118) and to the requirements of UN PED/TPED, DOT (USA) and TC (Canada).

For additional information about AMS Composite Cylinders or to order, please contact us today.