CGA’s P-63 Publication Recommends Safe, Environmentally Responsible Disposal Methods for Compressed Gases & Mixtures
July 15, 2021
When the need arises for disposal of compressed gases and their mixtures, it’s imperative that standards of health, safety, and environmental quality be maintained. In February 2021, the Compressed Gas Association (CGA) issued the 2nd edition of CGA P-63, Disposal of Gases. This recently revised safety standard recommends disposal methods for more than 140 gases and their mixtures, while also providing safe practices for the disposal of these gases’ containers, when such equipment is rendered unserviceable. Only environmentally acceptable methods are proposed in this publication.
The principles, recommendations, and requirements in CGA P-63 may be applied to both routine and emergency disposal operations. However, emergency disposal operations may dictate special or one of a kind procedures.
Dealing with damaged and/or unidentifiable containers (gas cylinders, drum tanks, and similar transportable and pressurized vessels) is often an integral part of the gas disposal operation. For this reason, guidance on the subject is included in this safety publication. However, such work is potentially dangerous and should only be performed by experienced and competent personnel following a risk assessment.
Steps to Dispose of Compressed Gases
Key operations for the safe remediation and/or disposal of contents and/or their containers may include:
- Identify container contents
- Select disposal method
- Safely dispose of container contents
- Evacuate and/or purge container
- Devalve container
- Remove any noxious residues from the container
- Render container unserviceable and scrap
NOTE: If doubt exists at any stage in the procedure, specialist advice should be obtained.
Gas Disposal Training & Safety
It is essential that all personnel engaged in the disposal of gases be properly trained and equipped and their practical competence established before they engage in disposal work. In specific cases, local certification may be required.
All operators undertaking gas disposal work should:
- be properly trained in practice and theory
- have written instructions/checklists
- be properly equipped with personal protective equipment (PPE)
- be provided with correctly designed disposal plant and equipment, and, if expected to deal with emergency situations, be trained to assemble emergency rigs from readily available materials
This publication may be used as an aid in the training of operators involved in the disposal of gases. The sections of CGA P-63 have been written with this goal in mind, and in particular, summary checklists have been added for use as training modules.
Selecting a Gas Disposal Method
There are many methods available for the disposal of compressed gases. Individuals should select an appropriate method for specific conditions. In the absence of a specific procedure, an appropriate method should be selected based on a risk assessment.
There are four principal methods of disposal, listed below in order of preference:
- burning or incineration
- venting to the atmosphere
Appendix A of CGA P-63 provides recommended disposal methods for all listed gases. When selecting a method of disposal for a particular gas or gas mixture, there are three important factors to consider:
- characteristics of the gas being treated
- local conditions, regulatory requirements, and operational constraints
- quantity of gas to be disposed
When disposing of a gas, personnel should exercise caution to avoid inadvertently creating new safety and/or environmental problems. For example, it is of little value to dispose of a gas by burning if the products of combustion released to the atmosphere will be just as toxic, if not more so, than the original gas being treated.
What’s New in This Edition
The 2nd edition of safety publication CGA P-63, Disposal of Gases, incorporates a number of significant updates, including:
- Updated and expanded training section
- Updated and expanded safety checklists
- Guidance on performing risk assessment before selecting and undertaking a particular disposal method
- Updated drawings and descriptions of various disposal methods
- Guidance for remediating and disposal of gas mixtures
- New section with extensive references of valve outlets, pressure relief devices, and valve types
- New section on specific hazards for remediation and disposal of diborane, diborane mixtures, and pentaborane
- Appendix A “Gas characteristics and recommended disposal methods”: tables updated and revised, with cautionary notes added about need for access to SDSs (safety data sheets) for all listed gases
For more details about this safety standard, the full Table of Contents may be downloaded for free from the CGA P-63 publication details page on the CGA portal.
CGA P-63, Disposal of Gases, is issued as part of a program of harmonization of industry standards, jointly produced by members of the International Harmonization Council.