Liquid oxygen therapy

Liquid oxygen may be recommended as the most appropriate form of oxygen therapy for ambulatory use dependent upon specific conditions and lifestyle.

Liquid oxygen equipment comprises of two main parts – a container or ‘dewar’ and a refillable portable unit.

Liquid oxygen dewar

The dewar contains liquid oxygen and it should only be used to fill the portable unit when the user wants to leave the house. If oxygen is needed at home, we recommend the concentrator is used.

Users should be familiar with the component parts of a portable oxygen unit before it is used.

To check the level of liquid oxygen in a dewar, press the liquid level switch for at least two seconds and read the liquid level display. Always reorder when it reaches a quarter full.

If the low battery indicator on the liquid level display lights up when the button is pressed, the user should inform the Air Products technician at the next visit.

Technical Data
Weight full	74 kg
Height	99 cm
Diameter	40.6 cm
Capacity	41 litres (liquid), 33,620 litres (gaseous)

Ordering liquid oxygen

A liquid oxygen dewar should last 4-6 weeks with normal use. The Air Products technician will arrange a delivery schedule with the oxygen user taking into account usage and the length of time the dewar will last. However, if any issues arise in the meantime, the user should call Air Products Homecare Helpline on 0800 373580, 8.00am-5.30pm, Monday to Friday.

A portable liquid oxygen unit

A portable liquid oxygen unit is designed to provide a source of oxygen to help a user to get out and about for extended periods of time, and is filled from the liquid oxygen dewar.

Users should be familiar with the component parts of a portable oxygen unit before it is used.

How to fill a portable unit

Only fill a portable liquid oxygen unit from the top of the dewar, following these instructions:

Clean and dry the fill connectors on both the dewar reservoir and the portable unit using a clean, dry, lint-free cloth. They must be dry to stop the two freezing together.
Turn the flow rate control on the portable liquid oxygen unit to the Off (O) position.
Position the portable unit’s fill connector – top fill (L) in an upright position over the reservoir connector on top of the liquid oxygen dewar.
Lower the portable unit onto the dewar reservoir (C) until you feel the connector engage.
Press firmly on the top of the portable unit keeping it in an upright position. The units are now joined together.
Open the vent valve (G) on the portable to begin filling the portable oxygen unit. Hold the portable oxygen unit down in place throughout the filling process.

Note:
Don’t worry if a hissing sound is heard, this is perfectly normal and is the sound of some oxygen escaping. Vapour may also be seen around the connection, this is due to the difference in temperature between the liquid oxygen and the warm air around the portable unit.

The unit is full when the hissing sound changes in tone and some liquid comes out of the vent line. When the liquid oxygen unit is full, close the portable vent valve (G).
After the portable unit is filled, closed the vent valve (G) and push the portable release button (D) on the liquid oxygen dewar until the units separate.

Caution:
If the portable unit does not separate easily, do not use force, the units may be frozen together. Wait until they warm up, they should then separate easily. Never touch any frosted parts. If liquid leaks after separation reattach the portable unit to the dewar immediately, then try again.

If there is excessive leakage to the point that there is a stream of liquid, leave the area and call Air Products on 0800 373580 immediately.

Note:
If refilling the portable unit immediately after a period of use, fill it and then wait 10 minutes with the flow control (K) set at zero. Then operate as normal.

How to use a portable unit

Push the nasal cannula firmly onto the oxygen outlet connector (H)
Put on the cannula
Turn the flow rate control (K) on top of the portable unit until the prescribed flow rate is visible in the flow rate window (N) and it clicks into place.
The oxygen level should be checked frequently, especially when using a portable unit away from home.
To turn the portable unit off, turn the flow control (K) anti-clockwise to the off position

Caution:
Always use a portable unit in the upright position. If it falls over or is laid on its side, the oxygen will vent very rapidly and make a loud chatter. If this happens simply return the portable unit to its upright position.

Never cover the portable unit or carry under clothing.

When using the portable unit in the car:

Always drape the portable shoulder strap over the front seat headrest.
Always open the car windows slightly to keep the car well ventilated
Never keep the portable unit in the boot of the car.

Checking the portable unit batteries (Spirit 600 only)

The green light on top of the portable unit will light up with each breath, showing that the portable unit is delivering oxygen. When the light is red it means the batteries need replacing. The unit will continue to deliver oxygen while the red light shows.

Note:
The green light will show with each breath even if the portable unit is empty

Cleaning the liquid oxygen system

Liquid oxygen systems require very little cleaning. However, if needed, it must be done in a clean environment. Avoid cleaning the equipment after vacuuming, under an open window, or in dusty, dirty or smoky environments.

Cleaning the portable unit

The portable unit may develop frost, this can be removed by tapping the unit and/or wiping any frost off the case.

When the portable unit is empty and has warmed up to room temperature, remove any moisture from the condensation pad.

Unzip the zipper at the base of the unit
Remove the pad and wring out any absorbed moisture. Allow the pad to dry completely.
Replace the pad in the unit and ensure the zipper is completely rezipped

Type of portable unit: Marathon

Technical Data
Weight full	2.5 kg
Height	38.1 cm
Capacity	0.85 litres (liquid) 685 litres (gaseous)
Evaporation rate	Approximately ⅓ in a 12 hour period when not in use

Flow rate (litres per minute)	Duration (Demand flow)	Duration (Continuous flow)
2	17 – 20 hours	5 hours 30 mins

Type of portable unit: Spirit 600

Technical Data
Weight full	2.54 kg
Height	29.2 cm
Capacity	0.63 litres (liquid) 516 litres (gaseous)
Evaporation rate	Approximately ¾ in a 12 hour period when not in use

Flow rate (litres per minute)	Duration (Demand flow)	Duration (Continuous flow)
2	17 hours	4 hours

Type of portable unit: Companion 1000

Technical Data
Weight full	3.7 kg
Height	35.3 cm
Capacity	1.25 litres (liquid) 1058 litres (gaseous)
Evaporation rate	Approximately ⅓ in a 12 hour period when not in use

Flow rate (litres per minute)	Duration (Continuous flow)
2	8 hours 30 mins

Type of portable unit: Companion T

Technical Data
Weight full	3.9 kg
Height	37.2.cm
Capacity	1.25 litres (liquid) 1058 litres (gaseous)
Evaporation rate	Approximately ⅓ in a 12 hour period when not in use

Flow rate (litres per minute)	Duration (Continuous flow)
2	8 hours 30 mins

Important safety instructions for liquid oxygen users

Never smoke while using oxygen. Keep oxygen equipment well away from naked flames such as gas cookers, open fires and candles.
Never touch the frosted connectors. Liquid oxygen is chilled to -34ºC. Skin burns may occur if a frosted part is touched. If contact occurs, flush well with cold water and call the doctor.
Never move the dewar without first consulting your Air Products technician.
Keep the dewar upright at all times. If it falls over on its side a stream of liquid oxygen may spill out of the reservoir. If a spill occurs, open doors and windows to ventilate the area and call us immediately on 0800 373580.
Never use oxygen in a fuel station and never smoke while using oxygen in the car.