Oxygen supply and sensors

Working with UK industry

At the beginning of the COVID pandemic there was concern over an adequate supply of oxygen for hospitals and care homes. The oxygen supply chain is from China and the US, so with restricted exports and increased demands the UK was exploring other sources. Shortfalls could potentially have been met by using other grades of oxygen, subject to appropriate validation which NPL could support, or by investigating the feasibility of other methods of oxygen production, such as electrolysis of water. NPL consulted with key suppliers to offer support and expertise.

There were also challenges getting oxygen to the new, temporary COVID beds within hospitals which were not on the existing network of oxygen supply. This could still be problem in a second wave and in developing countries, and portable devices may be required to provide oxygen.

Ventilators require an oxygen sensor to check that the concentration of oxygen in the oxygen/air gas mixture is correct. During the pandemic the supply chain for conventional sensors was exhausted and alternatives were required. NPL developed the concept of a novel electrochemical sensor based on a miniature fuel cell, which had the advantage of not requiring batteries and could be cheaper and more environmentally friendly than current sensors.

NPL has a longstanding relationship with Bramble Energy, a fuel cell manufacturer who were approached by NPL to produce a miniature oxygen sensor. NPL supported Bramble in its bid for funding from Innovate UK and has offered laboratory space and resource for the project. Bramble are working with NPL’s ventilator team to use this sensor in their novel design. Bramble own the IP for the sensor.