Administration of oxygen

Oxygen (O2) is administered as a corrective treatment for conditions

resulting in hypoxia (low level of oxygen in the blood).

Oxygen is classed as a medication and must be prescribed by a doctor and administered correctly to prevent over- or under-oxygenation.

Remember oxygen is NOT flammable, but it does aid combustion.

Patients and visitors should therefore be educated about the increased risk of fire and the precautions necessary to reduce this risk when supplementary oxygen is in use (see ‘General considerations’ below).

Oxygen must only be administered at the rate and percentage prescribed, as over-oxygenation can be dangerous for some individuals, particularly those with chronic lung disease who are retaining carbon dioxide, and infants, where there is also a risk of retinopathy.


The equipment required consists of a mask or nasal cannula that enables the administration of the prescribed dose (percentage); connection tubing; flow meter; wall or cylinder oxygen supply (oxygen cylinders are black with a white collar); and a humidifier with sterile water if required.


  • Explain procedure, addressing health and safety precautions, and ensure adequate understanding
  • Wash hands following correct procedure
  • Assemble equipment – For rates of 40% and over, humidification (moistening of the oxygen prior to it reaching the client) is essential
  • Set flow meter to prescribed rate, e.g. 2 litres per minute
  • Assist client to position mask (if mouth breathing) or nasal cannula correctly, ensuring a comfortable but not too tight a fit
  • Clients undergoing prolonged oxygen therapy will require monitoring of mucosa and frequent mouth/nasal care (minimum 2 hourly)
  • Encourage client to relieve the pressure of the mask or cannula from the face, nares and ears hourly as appropriate
  • Continue to monitor the client and promptly report any change in condition
  • Update nursing care plan