Oxygen Tank Regulators (Respiratory Therapy)

The content in Clinical Skills is evidence based and intended to be a guide to clinical practice. Always follow your organization’s practice.

ALERT

To prevent the risk of fire, do not allow the tank to come into contact with oil, grease, or highly flammable liquids.

Use only a wrench with an appropriate-size rectangular opening (Figure 1) to open and close the valve stem. Using a hexagonal wrench (Figure 2) could result in inadvertent loosening of the retaining nut on the stem of the tank, which could cause injury or death.

Never drop a tank or allow it to strike another surface. Make sure all oxygen tanks are secured in an appropriate oxygen stand and never left standing on end unsecured.

OVERVIEW

Oxygen tanks (also called cylinders) are used to provide portable oxygen when no piped oxygen source is available. The different sizes of oxygen tanks include the D cylinder, the E cylinder (Figure 3), the H cylinder, the K cylinder, and the M cylinder. E cylinders are the most common tanks used in the emergency department. D cylinders are commonly used for prehospital emergency medical services transport. M cylinders are used for many home health patients.

The reducing valve (sometimes called the adjustable regulator or control valve) reduces the tank pressure to a working pressure. The combination of a flowmeter with a reducing valve is called a regulator.^{undefined#ref2">2} The flowmeter controls and measures the flow of oxygen to the patient. In most cases, the regulator and flowmeter are coupled into one mechanical fitting for the oxygen tank. A yoke holds the regulator in place.

Another safety feature is the pin index system. Each gas uses a unique combination of pins on the regulator that corresponds to the holes on the valve stem (sometimes called the post valve or cylinder post) of the intended tank. A sealing washer (also called a washer, O-ring, or gasket) helps ensure a tight connection between the regulator and the valve stem (Figure 4).

The valve stem is opened and closed by means of an appropriate-shape wrench (also called a key) (Figure 1) or by turning a regulator knob. On removable regulators, the regulator yoke is tightened or loosened with a T-bar; a wrench may be used to provide extra leverage on the T-bar.

To eliminate the need to apply or replace a regulator on an oxygen tank, integrated oxygen tanks have been developed that can supply a high-pressure oxygen device. These newer systems include a built-in, nonremovable regulator with adjustable flow mechanisms (Figure 5).

SUPPLIES

See Supplies tab at the top of the page.

EDUCATION

Provide developmentally and culturally appropriate education based on the desire for knowledge, readiness to learn, and overall neurologic and psychosocial state.
If the patient is going home with an oxygen tank, teach the patient and family:
- How to change the oxygen regulator or reducing valve
- To store the extra tanks flat
- To never smoke while using oxygen and always keep oxygen tanks away from petroleum products, oil, grease, and flammable products
- To change the oxygen tank out when the gauge reads 500 psi
- To always use medical grade oxygen
Encourage questions and answer them as they arise.

ASSESSMENT AND PREPARATION

Preparation

Read the label on the tank to verify that it contains the desired gas.
Each tank must be labeled with its contents. Always read the label on the tank to confirm that it contains the desired gas.²
Use a portable carrier to move the tank to the point of use.
Do not drag, slide, roll, or drop a tank or allow it to strike another surface.
Obtain the correct tool to loosen and tighten the fittings on the tank.
Use only a wrench with an appropriate-size rectangular opening (Figure 1) to open and close the valve stem. Using a hexagonal wrench (Figure 2) could result in inadvertent loosening of the retaining nut on the stem of the tank, which could cause injury or death.

PROCEDURE

Application of Regulator or Reducing Valve

Perform hand hygiene. Don appropriate personal protective equipment (PPE) based on the patient’s need for isolation precautions or the risk of exposure to bodily fluids.
Alert the patient and nearby health care team members that the procedure is about to begin.
Secure the tank in a support stand or assigned location on the stretcher or transport cart.
Rationale: Using the support stand avoids damage to the tank during transport and storage.

Be aware that pressurized oxygen may turn the tank into a dangerous projectile if the regulator, the tank, or the valve stem is damaged.
Remove the protective seal from the valve stem, taking care not to lose the sealing washer.
Rationale: Misplaced or defective washers may cause leaks if the valve is not properly sealed. Misplaced or defective plastic washers can cause fires.¹
Inspect the opening to ensure that it is free of debris and dirt.
Rationale: Debris and dirt can interrupt flow in the tank.
Turn the valve stem outlet away from health care team members. Warn anyone present that a loud noise is going to occur.
Open the valve stem (by turning it counterclockwise) and close it quickly with the wrench. This will produce a whooshing sound. Remember which direction to turn the wrench by saying "righty tighty, lefty loosey."
Rationale: Opening and closing the valve stem quickly clears (cracks) the valve and eliminates dust or foreign materials.
Place the regulator or reducing valve on the tank, making sure that the fittings are compatible and that the sealing washer (Figure 4) is in place.
Tighten the regulator or reducing valve securely with the T-bar (Figure 6).
1. If the T-bar is too difficult to tighten sufficiently by hand, use a wrench as a lever on the T-bar (Figure 7).
2. Make sure the regulator or reducing valve is turned off.
Slowly open the cylinder valve stem with the wrench (Figure 1) until the pressure-gauge needle stops rising.
After the cylinder is turned on completely, turn the valve stem back one-quarter to one-half turn to prevent "valve freeze."² The pressure gauge on a full E-cylinder oxygen tank should read approximately 2200 psi.²
Assess the system for audible leaks.
1. If a leak is heard, close the valve stem, turn on the flowmeter to bleed all pressure from the regulator, and turn off the flowmeter.
2. Retighten the connections, open the valve stem, and reassess for leaks.
Check the pressure gauge to confirm a sufficient supply of gas. Follow the tank conversion factors (Table 1) to determine the duration. Replace the tank if it does not contain enough oxygen. Cylinders with 500 psi or less are considered at the refill level on bourdon gauges and should not be used if possible.²
1. Cylinder duration calculations: Knowing the tank size, calculate how long it will last.
2. Gas cylinder duration: The equation is (tank factor × psi) ÷ liter flow.
  Example: An E-cylinder oxygen tank pressure is 1000 psi. The patient is receiving oxygen at 4 L/min.
  
  (0.28 × 1000) ÷ 4 = 70 minutes of reliable tank life
Attach the nut and tailpiece (also called a Christmas tree adapter or green nipple connector) to the regulator or reducing valve in a clockwise motion until the connection is finger tight.
Connect the desired form of oxygen delivery device to the flowmeter.
Turn on the flowmeter to register the desired flow rate.
To prevent an accidental readjustment of oxygen flow, never drape anything over the tank or the regulator.
1. If using a ball-type flowmeter (Figure 6), make sure that the middle of the ball is at the desired level.
  Rationale: Ball-type flowmeters are constructed to be used in an upright position. Laying them on their side affects the accuracy of their reading but not the accuracy of the actual flow. An obstruction to the flow (e.g., crimped or pinched tubing) causes the ball to drop to the actual flow reaching the patient.
2. Needle-gauge flowmeters (Figure 8) may be used in any position without affecting the accuracy of their reading. An obstruction to the flow will cause the gauge to register higher than the actual flow being delivered to the patient.
When the tank is not in use, close the valve stem and bleed the system by turning the flowmeter on until all of the gas is evacuated from the regulator.
Rationale: Removing the pressure decreases the danger of the tank becoming a dangerous projectile if it is inadvertently knocked over or dropped with the regulator in place.
Discard supplies, remove PPE, and perform hand hygiene.

Removal of Regulator or Reducing Valve (Removable Regulators or Reducing Valves)

Perform hand hygiene. Don appropriate PPE based on the patient’s need for isolation precautions or the risk of exposure to bodily fluids.
Alert the patient and nearby health care team members that the procedure is about to begin.
Secure the tank in a support stand or assigned location on the stretcher or transport cart.
Rationale: Using the support stand avoids damage to the tank during transport and storage.

Be aware that pressurized oxygen may turn the tank into a dangerous projectile if the regulator, the tank, or the valve stem is damaged.
Close the valve stem with an appropriate wrench.
Turn on the flowmeter to bleed the system until all of the gas is evacuated from the regulator. Turn the flowmeter off.
Loosen the yoke by turning the T-bar (Figure 6) and remove the regulator or reducing valve. If the T-bar is too tight to loosen manually, use a wrench as a lever on the T-bar (Figure 7).
Label the tank “empty” or “in use” and store it in a rack.
Discard supplies, remove PPE, and perform hand hygiene.

MONITORING AND CARE

When the patient is using the oxygen tank, monitor for safety and proper use.

EXPECTED OUTCOMES

Successful application or removal of oxygen tank regulator or reducing valve

UNEXPECTED OUTCOMES

Injury or death of patient, health care team member, or bystander
Loss of oxygen caused by improper seal

DOCUMENTATION

Education
Unexpected outcomes and related interventions

REFERENCES

Anesthesia Patient Safety Foundation (APSF). (2006). FDA and NIOSH issue warning about oxygen regulator fires and incorrect use of seals. Retrieved September 25, 2023, from https://www.apsf.org/article/fda-and-niosh-issue-warning-about-oxygen-regulator-fires-and-incorrect-use-of-seals/ (classic reference)* (Level VII)
Vines, D.L. (2021). Chapter 41: Storage and delivery of medical gases. In R.M. Kacmarek, J.K. Stoller, A.J. Heuer (Eds.), Egan's fundamentals of respiratory care (12th ed., pp. 884-905). St. Louis: Elsevier.

ADDITIONAL READINGS

USA Safety. (n.d.). Gas cylinder safety regulations and guidelines. Retrieved September 25, 2023, from https://www.usasafety.com/regulations.php

*In these skills, a "classic" reference is a widely cited, standard work of established excellence that significantly affects current practice and may also represent the foundational research for practice.

Elsevier Skills Levels of Evidence

Level I - Systematic review of all relevant randomized controlled trials
Level II - At least one well-designed randomized controlled trial
Level III - Well-designed controlled trials without randomization
Level IV - Well-designed case-controlled or cohort studies
Level V - Descriptive or qualitative studies
Level VI - Single descriptive or qualitative study
Level VII - Authority opinion or expert committee reports

Clinical Review: Justin J. Milici, MSN, RN, CEN, CPEN, CPN, TCRN, CCRN, FAEN

Published: November 2023