Gas Cylinders


Article Author:
Derek King


Article Editor:
Michael Decker


Editors In Chief:
Russell McAllister
Jason Widrich
Daniel Sizemore


Managing Editors:
Avais Raja
Orawan Chaigasame
Carrie Smith
Abdul Waheed
Khalid Alsayouri
Trevor Nezwek
Radia Jamil
Patrick Le
Anoosh Zafar Gondal
Saad Nazir
William Gossman
Hassam Zulfiqar
Hussain Sajjad
Steve Bhimji
Muhammad Hashmi
John Shell
Matthew Varacallo
Heba Mahdy
Ahmad Malik
Sarosh Vaqar
Mark Pellegrini
James Hughes
Beata Beatty
Beenish Sohail
Nazia Sadiq
Hajira Basit
Phillip Hynes


Updated:
6/18/2019 4:51:28 AM

Introduction

A gas cylinder is a containment apparatus that will store a gaseous compound under pressure for use in medical settings. The physical form of the stored compound can be gas and/or liquid, with the ultimate output from the apparatus being gaseous. Gas cylinders allow for portable and safe storage of compounds needed in a medical setting. The sizing of gas cylinders has been attributed to a nationally recognized letter, with the more commonly used medical sizes listed below. Gas cylinders are labeled from A to M, with increasing volume as the letters of the alphabet proceeds. E sized cylinders are the most commonly used size in medical settings. E cylinders have a service pressure of 1900 psig, however, and may be filled up to 10% more to 2200 psi. This will allow for expansion at higher temperatures (greater than 70 degrees Fahrenheit).[1][2][3]

Container Sizes

The following are standard container sizes and the volume of oxygen contained at 2200 psig (maximum).

  • B: 200 L
  • D: 425 L
  • E: 660 L
  • F: 1360 L
  • G: 3400 L
  • M: 3450 L

Color System for Compounds

A standardized color system identifies the compound in the container. The United States color system for oxygen and air differs from the colors used internationally:

  • Oxygen - Green (*White)
  • Carbon Dioxide - Gray
  • Nitrous Oxide - Blue
  • Nitrogen - Black
  • Helium - Brown
  • Air - Yellow (*White & Black)

*International color

In order to prevent connecting the wrong gas cylinders, a safety system is in place. This system, called the Pin Index Safety System, provides a standardized, unique pin configuration system that acts as a lock and key system to prevent the mismatching of gas cylinders with their corresponding connections in medical settings.

Function

Pressure Release Device

The release of pressurized gas can be hazardous, and extreme caution should be exercised. Gas pressure levels should be reduced from stored high pressure to a workable, usable level. A pressure regulator should be used in this situation and any time contents are being removed or used from the cylinder. Do not tamper with pressure release devices. Do not use any cylinders with visibly defective pressure release devices. Pressure release devices and gas outlets should never be pointed in any direction that could cause harm.

While attached to an anesthesia machine, the cylinder valves should be in the off position while not in use. This is to prevent leakage and so that the provider will be notified via an alarm of failure of the pipeline supply of gas. If the cylinder were to be left open and a pipeline gas supply failure occurred, the anesthesia machine would consume the oxygen in the cylinder, and the provider would not be notified until the cylinder was depleted.[4][5]

Issues of Concern

Safe Usage

A cylinder should be inspected for malfunctions and defects before use. Full cylinders are usually placed with a tamper-evident seal. This is generally a tear-off seal on the outlet of the valve and is removed before use. Proper inspection of a cylinder includes the outlet, pin index safety system, and especially, the pressure relief device. The valve outlet should be clean before use. Only use cylinders marked with DOT (Department of Transportation) or ICC (Interstate Commerce Commission). In Canada, cylinders may be marked with BTC (Board of Transportation Commissioners) or CTC (Canadian Transport Commission). A cylinder should be connected to a regulator to bring the compressed, stored pressure down to a working, usable pressure. Inspect the regulator for signs of damage or foreign materials.[6]

Safe Storage and Transportation

Cylinders must be stored safely; they should not be stored upright and unsecured. Cylinders can fall over when unsecured. If a cylinder cannot be stored upright, it is safer to store it on its side. However, caution should be exercised so that people do not trip over or damage a cylinder. Always transport cylinders using a cart or carrier. Never drag, roll or slide cylinders, even for a short distance. Do not drop or hit cylinders. Only qualified personnel should refill cylinders. While using cylinders, avoid flammable substances, smoking, open flame, or any other incendiary sources. Store cylinders in dry, cool, well-ventilated areas and away from exposure to weather. Cylinder valves should be stored in temperatures less than 125 degrees Fahrenheit/52 degrees Centigrade. Separate full and empty cylinders to prevent the accidental usage of an empty cylinder during an emergency situation.

Clinical Significance

Use Boyle's law to calculate how much oxygen time is remaining in an E-sized cylinder. Boyle's law states that at a fixed temperature (room temperature) of an ideal gas, pressure is inversely proportional to volume. Boyle's law can be further rearranged to state that pressure times volume is equal to a constant. The following is the formula:

  • P1 * V1 = P2 * V2.

One could compare a cylinder of gas at filled volume (V1 = 660L) and pressure (P1 = 2200psig) to the current pressure (P2) read on the cylinder. This would provide the information needed to solve for the current volume (V2) remaining in the tank in liters. The following is the formula:

  • P2/P1 * V1 = V2, or

(Measured pressure remaining using the integrated pressure gauge in psi/2200psi) *660L = Liters of oxygen remaining in the tank.

This Volume (V2) can be used to determine the amount of unit time remaining left on the cylinder, given a current flow rate of the gas.

  • V2/Flow rate = unit time remaining, or
  • Liters of oxygen remaining in the tank/oxygen setting in liters/minute = Minutes of oxygen remaining

The same formulas can be used in cylinders with pure gaseous form. To calculate for nitrous oxide, however, is only applicable once the pressure drops below 745 psi. This is due to having the liquid and gaseous form within the tank. The pressure will remain constant until 75% of the 1590 L gas is consumed, which is approximately equal to 400 L remaining within the cylinder. From this point until empty, the above formulas apply. Prior to this point, the cylinder must be weighed to determine the amount of gas remaining within the cylinder.

Other Issues

The transportation of gas cylinders is highly regulated by both local, state and federal agencies in most countries. In the UD, the Department of Transportation is the governing authority. Further, there are guidelines for the manufacturer to ensure that the cylinders have been tested and are safe. Some of the tests that cylinders undergo include tensile strength, hydrostatic test, impact testing, burst testing and pressure cycling. Once the cylinder is manufactured, it must have all the vital information permanently etched on to the cylinder.[7]


Interested in Participating?

We are looking for contributors to author, edit, and peer review our vast library of review articles and multiple choice questions. In as little as 2-3 hours you can make a significant contribution to your specialty. In return for a small amount of your time, you will receive free access to all content and you will be published as an author or editor in eBooks, apps, online CME/CE activities, and an online Learning Management System for students, teachers, and program directors that allows access to review materials in over 500 specialties.

Improve Content - Become an Author or Editor

This is an academic project designed to provide inexpensive peer-reviewed Apps, eBooks, and very soon an online CME/CE system to help students identify weaknesses and improve knowledge. We would like you to consider being an author or editor. Please click here to learn more. Thank you for you for your interest, the StatPearls Publishing Editorial Team.

Gas Cylinders - Questions

Take a quiz of the questions on this article.

Take Quiz
Which following gas tank has the highest volume?



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up
Medical gas cylinders are color-coded to allow healthcare professionals to quickly identify what gas is being used. What cylinders have a different color in Canada compared to the United States?



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up
How many liters of oxygen does an E cylinder of oxygen contain when its gauge is reading 950 psi.



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up
If a patient has a nasal cannula on and it is set at 5 L/min, how long will an E cylinder of oxygen last before depletion if its gauge is reading 1000 psi?



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up
At what volume of gas does a nitrous oxide (N2O) E cylinder start to show a pressure below 745 psi?



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up
Which color tank and gaseous pairing are correct in the choices below using US standard color system?



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up

Gas Cylinders - References

References

Kim B,Oh S,Jung J,Lee JH, Investigation of adsorption characteristics of four toxic gases (nitric oxide, nitrogen dioxide, sulfur dioxide, and hydrogen chloride) on the inner surface of nickel-coated manganese steel cylinders and aluminum cylinders. Journal of the Air     [PubMed]
Srivastava U, Anaesthesia gas supply: gas cylinders. Indian journal of anaesthesia. 2013 Sep;     [PubMed]
Das S,Chattopadhyay S,Bose P, The anaesthesia gas supply system. Indian journal of anaesthesia. 2013 Sep;     [PubMed]
Blakeman TC,Branson RD, Oxygen supplies in disaster management. Respiratory care. 2013 Jan;     [PubMed]
Feldman JM,Kalli I, Equipment and environmental issues for nonoperating room anesthesia. Current opinion in anaesthesiology. 2006 Aug;     [PubMed]
Tawhai MH,Lin CL, Airway gas flow. Comprehensive Physiology. 2011 Jul;     [PubMed]
Stoller JK,Stefanak M,Orens D,Burkhart J, The hospital oxygen supply: an     [PubMed]

Disclaimer

The intent of StatPearls is to provide practice questions and explanations to assist you in identifying and resolving knowledge deficits. These questions and explanations are not intended to be a source of the knowledge base of all of medicine, nor is it intended to be a board or certification review of Anesthesiology. The authors or editors do not warrant the information is complete or accurate. The reader is encouraged to verify each answer and explanation in several references. All drug indications and dosages should be verified before administration.

StatPearls offers the most comprehensive database of free multiple-choice questions with explanations and short review chapters ever developed. This system helps physicians, medical students, dentists, nurses, pharmacists, and allied health professionals identify education deficits and learn new concepts. StatPearls is not a board or certification review system for Anesthesiology, it is a learning system that you can use to help improve your knowledge base of medicine for life-long learning. StatPearls will help you identify your weaknesses so that when you are ready to study for a board or certification exam in Anesthesiology, you will already be prepared.

Our content is updated continuously through a multi-step peer review process that will help you be prepared and review for a thorough knowledge of Anesthesiology. When it is time for the Anesthesiology board and certification exam, you will already be ready. Besides online study quizzes, we also publish our peer-reviewed content in eBooks and mobile Apps. We also offer inexpensive CME/CE, so our content can be used to attain education credits while you study Anesthesiology.