Oxygen therapy is playing an increasingly integral role in healthcare and home care.

With the growing number of patients worldwide suffering from COPD, asthma and other respiratory conditions, providing a practical, lightweight and cost-effective oxygen therapy package has never been more important.

In this post, AMS Composite Cylinders Director, James Cooper, explores some of the key benefits of Non-Limited Life (NLL) Composite Cylinders over standard life composite, and aluminium models – to both gas cylinder customers and patients requiring oxygen therapy.

Composite Cylinders vs Aluminium

Patients that require oxygen therapy are often elderly or infirm. Having a lower weight, portable oxygen delivery system that can be used by ambulatory patients can be the difference between maintaining independence and basic freedom, and becoming reliant on external care and family support.

This is why, when it comes to designing valve and cylinder packages for oxygen therapy, every gram saved makes a huge difference. With limited progress on reducing the weight of brass valves, the only way to reduce the weight of packages is through choosing the right medical gas cylinder.

Today, a fully wrapped carbon fibre cylinder typically weighs around 50% of a contemporary aluminium cylinder – something that translates directly into increased portability and improved freedoms for patients requiring oxygen therapy at home. As an added benefit, carbon fibre wrapped cylinders can also handle higher pressures. They can be filled with more oxygen, extending the periods between refills.

NLL vs Standard Life

Traditionally, all refillable gas cylinders have been supplied with a defined maximum lifespan. Previously, with fully wrapped cylinders, the industry standard has been 15 years. After this point, the cylinder can no longer be used, and most be disposed of accordingly. Disposing of cylinders at the end of their life is both costly and an unnecessary waste of resources. NLL cylinders avoid this cost.

In 2013, changes to the ISO standards enabled the introduction of Non-Limited Life (NLL) cylinders for the first time. New fully wrapped carbon fibre cylinders produced to NLL specifications have no maximum lifespan. They require testing every 5 years, and as long as they pass, they can be used indefinitely. In real world applications such as oxygen therapy, NLL cylinders will typically last more than twice as long as standard rated products.

Currently, many manufacturers have been reluctant to embrace the new NLL standard, and are continuing to produce 15 year rated products. At AMS Composite Cylinders, we have introduced a range of NLL carbon composite cylinders – in an effort to reduce costs for both service suppliers and end users alike.

NLL – cutting the cost of carbon composite

Traditionally, one of the biggest drawbacks of carbon composite cylinders was the cost. In the past, they commanded a significant premium over aluminium cylinders.

When combined with the limited lifespan and higher disposal costs, cost-conscious customers simply couldn’t justify investing in composite cylinders, despite the patient benefits.

Over time, the cost of carbon composite cylinders has fallen, and with the introduction of NLL – they have become significantly more competitive, for the benefit of both buyers and oxygen therapy patients. Today, an NLL fully wrapped carbon fibre cylinder from AMS Composite Cylinders costs no more than an equivalent limited life product from many other manufacturers.

Lightweight Oxygen Therapy Cylinders from AMS

AMS Composite Cylinders is the exclusive continental European and UK distributor for an advanced range of lightweight composite gas cylinders from Advanced Material Systems (AMS).

Products include carbon composite cylinders for a wide variety of breathing air and oxygen therapy applications, including healthcare, respiratory, SCBA (Self-Contained Breathing Apparatus), laboratory, emergency and environmental uses.

Our light composite gas cylinders offer high pressure (300 Bar), NLL (Non-Limited Life) performance, and are accredited for use worldwide – holding a wide range of quality assurance accreditations, including: ISO 11119-2, UN-TPED Pi, DOT (USA) and TC (Canada).


Additional information about AMS Composite Cylinders and our products can be found at www.ams-composites.com.