TITLE:	ES&H Manual
DOCUMENT ID:	6150 Appendix T1 Gas[1] Hazard Classes and Safety Requirements

Jefferson Lab has determined that working with gas(es) carries an unmitigated Risk Code >2. At a minimum all tasks requiring gases are discussed with the supervisor prior to commencement. An Operational Safety Procedure (OSP) is written for work considered to be Risk Code >2 in accordance with ES&H Manual Chapter 3210 Work Planning, Control, and Authorization Process.

1.0 Purpose

Gases are divided into hazard classes according to their characteristics and likely reactions to other materials. Correct identification of a gas’ hazard class is essential to providing appropriate safeguards. Jefferson Lab complies with hazard classes recognized by the industry standards outlined in ES&H Manual Chapter 2410 Appendix T1 Hazard Issues List.

2.0 Scope

It is recognized that listing the requirements for every gas used at Jefferson Lab would be prohibitive, it is therefore required that Qualified Gas Workers read the gas’ material safety data sheet (MSDS) and follow the recommendations provided. This appendix defines Jefferson Lab’s requirements in additional to those listed on the MSDS.

All gas cylinders are to be secured at all times. Cylinders not in use are to be capped.

This document is produced in coordination with ES&H Manual Chapter 6150 Compressed, Liquefied, and Solidified Gas Program.

3.0 Responsibilities

NOTE: Management authority may be delegated at the discretion of the responsible manager.

3.1 Anyone at Jefferson Lab

· Contact Industrial Hygiene to perform a hazard evaluation if gas cylinders, signs/labels, or other issues do not meet with the requirements of this appendix.

3.2 Industrial Hygiene

· Perform hazard evaluations and approve areas for specific gas use and storage, as requested.

· Provide safety labels and signs, as required/requested.

4.0 Gas Hazard Classes and Minimum Safety Requirements

A gas’ MSDS lists its hazard class and associated safety requirements (see ES&H Manual Chapter 6610 Appendix T2 Material Safety Data Sheets). All gases are classified by their primary hazards, but may have one or more secondary hazards. Jefferson Lab implements administrative and engineering control measures to protect workers from all associated hazards. Hazard classes of gases used at Jefferson Lab include:

Flammables	Oxidizer	Corrosive
Non-Flammable	Toxic/Poison	Cryogenics

(These are example of typical signage/labels developed by the US Department of Transportation Pipeline and Hazardous Materials Safety Administration. Variations are acceptable.)

4.1 Flammables

Gas that, at ambient temperature and pressure, forms a flammable mixture with air at a concentration of thirteen (13) percent by volume or less; or a gas that, at ambient temperature and pressure, forms a range of flammable mixtures with air wider than twelve (12) percent by volume, regardless of the lower limit;

4.1.1 Primary Hazard

· Fire/explosion

4.1.2 Secondary Hazard

· Oxygen displacement (see ES&H Manual Chapter 6540 Oxygen Deficiency Hazard Control Program)

· Toxic

· Highly reactive

· Sudden release of pressure

4.1.3 Safety Requirements

· Signage, posted in areas where gas is used and stored (e.g., “Danger – Flammable Gas,” “No Ignition Sources,” “No Smoking or Open Flames”). (Request appropriate (new or replacement signs) from Industrial Hygiene).

· A posted list of responsible persons and their contact numbers.

· Cylinders are stored a minimum of 20-feet away from any source of oxygen (or other oxidizer); or separated by a 5-foot, half-hour, fire-rated wall.

· Fire extinguishers available in storage and work areas.

· Any source of spark or flame is controlled by a work control document.

· Cylinders, lines, and equipment are bonded and grounded.

· Ventilation of one or more air changes per hour. (This is not applicable to outdoor Jefferson Lab storage.)

4.2 Non-Flammable

Non-flammable gas is gas that does not burn. It is used during chemical synthesis, chemical analysis, or preservation of reactive materials.

4.2.1 Primary Hazard

· Oxygen displacement (except oxygen) (see ES&H Manual Chapter 6540 Oxygen Deficiency Hazard Control Program)

4.2.2 Secondary Hazard

· Sudden release of pressure

4.2.3 Safety Requirements

· At a minimum it requires an ODH Safety Review (see ES&H Manual Chapter 6540 Oxygen Deficiency Hazard Control Program)

· Signage, posted in areas where gas is used and stored (e.g., “Danger – Non-Flammable Gas”). (Request appropriate (new or replacement signs) from Industrial Hygiene).

· Continuous ventilation of the area during use.

4.3 Oxidizer

A gas that initiates or promotes combustion in other materials, thereby causing fire either of itself or through the release of oxygen or other gases.

4.3.1 Primary Hazard

· Supports combustion.

4.3.2 Secondary Hazard

· Oxygen displacement (except oxygen) (see ES&H Manual Chapter 6540 Oxygen Deficiency Hazard Control Program)

· Fire/explosion

· Toxic

· Highly reactive

· Sudden release of pressure

4.3.3 Safety Requirements

· Signage in areas where gas is used and stored (e.g., “No Smoking or Open Flames”). (Request appropriate (new or replacement signs) from Industrial Hygiene).

· Cylinders are stored 20 feet away from flammables; or separated by a 5-foot, half-hour, fire-rated wall.

· Oil, grease, or other easily combustible materials are prohibited in or around cylinders.

· Any source of spark or flame is controlled by a work control document.

4.4 Toxic/Poison

Toxic or poisonous gas causes damage to living tissue, endangers life, or brings about death. Those that do so at low concentrations are “highly toxic.”

4.4.1 Primary Hazard

· Lethal or harmful to humans.

4.4.2 Secondary Hazard

· Fire/explosion

· Highly reactive

· Sudden release of pressure

4.4.3 Safety Requirements

· Strict adherence to the MSDS’ safety requirements for Threshold Limit Values (TLV) and ventilation requirements.

· Minimize exposure - don specialized personal protective equipment (PPE).

4.5 Corrosive

A gas that causes visible destruction of, or irreversible alterations in, living tissue by chemical action at the site of contact.

4.5.1 Primary Hazard

· Damage to living tissue or material.

4.5.2 Secondary Hazard

· Fire/explosion

· Oxidation

· Toxic

· Highly reactive

· Sudden release of pressure

4.5.3 Safety Requirements

· Strict adherence to the MSDS’ safety requirements for TLVs and ventilation requirements.

· Minimum exposure - don specialized PPE.

· Inspect cylinder and valve for corrosion prior to use.

· If the valve or delivery system does not release the gas contact the supplier.

4.6 Cryogenics (see ES&H Manual Chapter 6540 Oxygen Deficiency Hazard Control Program for further details.)

Cryogenic liquids/gases are extremely cold and can rapidly freeze tissue and other materials.

4.6.1 Primary Hazard

· Damage to tissue or material.

· Oxygen displacement (except oxygen) (see ES&H Manual Chapter 6540 Oxygen Deficiency Hazard Control Program)

4.6.2 Secondary Hazard

· Fire/explosion

· Toxic

· Oxidation

· Sudden release of pressure

4.6.3 Safety Requirements

· Strict adherence to the MSDS’ safety requirements for TLVs and ventilation requirements.

· Minimum exposure - don specialized personal protective equipment (PPE).

5.0 Commonly Used Gases

The gases most commonly used at Jefferson Lab and their primary hazards classes are listed in the table below.

Gas	Primary Hazard Class
Acetylene Deuterium Dimethyl Ether Ethane Isobutane Hydrogen Methane Propane	Flammables
Argon Carbon Dioxide Helium Nitrogen Refrigerant (R-12, R-22, and other halogenated hydrocarbons) Sulfur Hexaflouride	Non-Flammables
Oxygen Air Clorine Fluorine Nitric Oxide Nitrogen Dioxide	Oxidizer
Chlorine	Toxic/Poison

6.0 References

Occupational Safety and Health Administration Standard 1910.1200 Hazard Communication (c) Definitions

7.0 Revision Summary

Revision 1 – 06/15/11 – Updated to reflect current laboratory operations.

ISSUING AUTHORITY	TECHNICAL POINT-OF-CONTACT	APPROVAL DATE	EXPIRATION DATE	REV.
ESH&Q Division	Tim Minga	06/15/2011	06/16/2016	1

This document is controlled as an on line file. It may be printed but the print copy is not a controlled document. It is the user’s responsibility to ensure that the document is the same revision as the current on line file. This copy was printed on 7/25/2012.

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[1] For the purpose of this appendix the term “gas” is used, in its singular or plural form, to mean compressed, liquefied, and/or solidified gas.