Commercially available OEUs generally work till an altitude of 8,000 feet above sea level; with an optional plug-in module, CSIR's unit can work up to an altitude of 14,000 feet

An oxygen enrichment unit (OEU) developed indigenously by the Council for Scientific and Industrial Research (CSIR) to treat Covid patients has a spin-off for the defence forces in high-altitude areas as it can be used at heights where such equipment normally does not function.

Commercially available OEUs generally work till an altitude of 8,000 feet above sea level. With an optional plug-in module, CSIR's unit can work up to an altitude of 14,000 feet, thereby making it handy for use during contingencies in high-altitude battlefield areas where rarefied air and extreme climate can cause medical emergencies.

OEU is a device which concentrates oxygen from the surrounding air by selectively removing nitrogen to supply oxygen-enriched air. The concentrated oxygen is delivered to patients with respiratory problems through a mask or a nasal cannula.

Designed by CSIR’s Central Mechanical Engineering Research Institute (CMERI), the device may be used in remote places, homes or hospitals for patients with chronic obstructive pulmonary diseases (COPD), chronic hypoxemia and pulmonary Edema. It can also be used as an adjunct treatment for severe sleep apnoea in conjunction with a continuous positive airway pressure unit.

According to Prof Harish Hirani, director, CMERI, the unit may be very useful for homes and hospitals as well as defence forces, particularly in high-altitude terrain and remote localities, besides being more effective and crucial for treating Covid patients. He said this unit might reduce the demand for oxygen cylinders and ventilators and due to the rise in air pollution its demand is expected to grow rapidly as it is useful in maintaining proper oxygen levels for an optimum healthy environment.

The unit works on the principle of “pressure swing adsorption” to remove nitrogen from the air under certain pressure using a compressor and valves, thereby increasing the oxygen concentration.

CSIR’s unit is capable of delivering up to 30 litre per minute (LPM) of oxygen-enriched air, which is absent in the other commercially available units. It is claimed to give an outflow of 93 per cent oxygen concentration level as compared to 27-35 per cent by other units. The machine can also regulate air flow with accuracy 0.5 LPM, which will help in high-flow oxygen therapy, a better method in treatment and management of Covid patients.

After testing, validation and benchmarking, the technology for manufacturing the OEU has been transferred by CMERI to a private firm for commercial production and a unit costs about Rs 35,000.