Introduction

Welding, cutting, and grinding of metal is a common part of Jefferson Lab fabrication and construction activities. Because of the high temperatures involved and the potential for fire and serious personal injury, care must be taken to ensure that work is performed safely.

• This chapter is primarily a guide for workers and supervisors who use welding, cutting, and grinding processes. It applies to all welding, hot cutting, and abrasive grinding on site by employees, users, temporary help, or subcontractors.
• Work which involves an open flame or produces sparks is specially restricted and must be specifically authorized via a Fire Hazard Work Permit or Operational Safety Procedure. The permitting process requires the supervisor of the work to inspect the area to ensure that preparations are complete and safe conditions exist.
• Fire Hazard Work Permits are valid for a specified time not exceeding 14 days. See Appendix 6122-T1 Use of Fire-Hazard Work Permits for more information.
• A permanent welding or cutting area may be established via an approved Operational Safety Procedure. See Chapter 3310 Standard Operating Procedures and Operational Safety Procedures for more information.

Hazard Avoidance

Experience

Approximately 6% of fires on industrial properties are caused by welding and cutting, primarily from sparks produced by portable equipment in areas not specifically designed or approved for such work.

• Electric arcs or oxy-fuel gas flames have rarely caused fire except where they have overheated combustibles in the vicinity of the work.
• At Jefferson Lab, weld spatter caused a minor fire in the North Linac Service Building in 1991.
• A Jefferson Lab employee received a significant "sunburn" from UV exposure while working near an arc welding area in 1993.

If you are not involved with welding and cutting, you can avoid hazards by following these precautions:

• Observe and follow warning signs.
• Do not bring combustibles into an area where welding, cutting or grinding occurs.
• When passing through a fabrication work area, be aware that welding may be in progress, and stay on marked walkways.

Arc welding produces an intense bright light which can quickly cause eye damage and "sunburn".

• When you are in an area with arc welding in progress, do not look at the arc or its reflection off of shiny surfaces.
• If you encounter exposure to a welding arc, correct the situation with the welder, supervisor, and area safety warden.

Responsibilities

Worker

• Do not operate welding, cutting, or brazing equipment without specific authorization by your supervisor.
• Follow all guidance in this chapter and any authorizing Fire Hazard Work Permit or Operational Safety Procedure.
• Take the initiative to work safely.

Fire watch

• Remain present and undistracted during hot work operations.
• Be alert for any condition which could lead to a fire.
• Guard passersby from welding hazards.
• Interrupt the work when a hazardous condition develops, and deal with the situation appropriately.
• Remain on the scene for at least thirty minutes after completion of hot work to detect and report a fire resulting from stored heat.

Supervisor or inspector

Supervisors are responsible for authorizing and ensuring safe welding, or cutting, and grinding operations:

• Physically inspect the area before work begins.
• Ensure that personnel involved are appropriately trained.
• Ensure that the area is appropriately configured and made firesafe.
• Recognize and address potential complications such as environmental or radiological conditions or the effect of operations on other nearby activities.
• Coordinate fire hazards with the area Safety Warden and Building Manager (if applicable.)

Qualifications

Welder

Only personnel who have been properly instructed and qualified by their supervisor may operate welding and cutting equipment at Jefferson Lab.

Fire watch

A fire watch must be trained in the use of the available fire extinguishers and familiar with:

• All exit routes from the building.
• Use of the building fire alarm system (closest pull station).
• Emergency procedures in the event of fire (911 calls, for example).

Refer to the Fire Safety Chapters 6900 for additional information.

Program Summary

Fuel-gas welding and cutting and spark-producing cutting and grinding are restricted activities on the Jefferson Lab site. These activities are permitted only in areas that have been made firesafe.

• Open flame and spark-producing work is authorized only by a current Fire Hazard Work Permit or an Operational Safety Procedure for a specific area.
• Fire Hazard Work Permits are valid for a specified time not exceeding 14 days. See Appendix 6122-T1 Use of Fire-Hazard Work Permits for more information.
• A permanent work area for fire-hazardous operations may be established via an approved Operational Safety Procedure. See Chapter 3310 Standard Operating Procedures and Operational Safety Procedures for more information.
• The procedures in an authorizing OSP must be consistent with those required for a standard Fire Hazard Work Permit.

General Requirements

• Do not cut, weld, or grind inside a building if you have reason to suspect the sprinkler system (if present) is not working properly.
• Do not cut, or weld, in the presence of explosive atmospheres (gases, vapors, or dusts).
• Do not cut, weld, or grind on drums, barrels, tanks, or other containers until they have been thoroughly cleaned and declared free of flammable or combustible materials and gases.
• If the object to be worked cannot readily be moved to a routine welding area, move all combustible material in the vicinity to a safe place.
• If the object to be worked or cut cannot be moved and if all fire hazards cannot be removed, then protect the immovable fire hazards with appropriate guards and covers.
• Check cracks and holes in floors, walls, and ceilings to ensure that no combustible materials will be exposed to sparks should they pass through a crack or hole.
• Ensure that suitable fire extinguishing equipment is available.
• If material capable of causing a Class D fire is present, ensure that the fire extinguishing equipment is suitable for that case.
• Ensure that appropriate shields or welding curtains are in place to protect passersby and nearby workers.
• If in doubt about the safety of a new welding, cutting, or grinding area, inform Plant Services (Extension 7400). Plant Services will inspect the area and assist you in addressing fire hazards and the adequacy of the fire alarm system. They may also need to make temporary adjustments to fire detection systems.
• Do not cut, weld, or grind material which is known or suspected to be radiologically activated. Treat such material in a manner consistent with the Jefferson Lab Radiation Safety Program summarized in 6310 Ionizing Radiation Protection and associated app endices. You can call the Radiological Control staff at Extension 7236 for information, guidance, or assistance.

Inspection

The person responsible for authorizing the cutting and welding operation must physically inspect the area before work can begin.

Fire Watch

Whenever a Fire Hazard Work Permit is required for work, a fire watch must be designated if any of the following conditions exist:

• A significant amount of combustible material is closer than 35 ft (10.7 m) to the point of operations.
• A significant amount of combustible material is more than 35 ft (10.7 m) away, but could be easily ignited by sparks.
• Wall or floor openings within a 35-ft (10.7 m) radius expose combustible materials in adjacent areas, including concealed spaces in walls or floors.
• Combustible materials are adjacent to the opposite side of metal partitions, walls, ceilings, or roofs and could be ignited by conduction or radiation.

More than one fire watch may be required, depending on the situation.

Other safety concerns

• Welders and those performing similar work must wear appropriate personal protective equipment such as face shields, leather gloves, and leather aprons which are designed to prevent burns by protecting skin and clothing from welding slag, sparks, UV radia tion, and radiant heat. For additional information, see Chapter 6620 Personal Protective Equipment.
• Welding, cutting, and grinding may present other safety hazards besides heat and fire. The glare of an arc can cause serious damage to eyes. Chapter 6650 Vision Protection discusses the use of special glasses, goggles, and shields to protect eyes from th e glare of hot work. The Respiratory Protection Program found in Chapter 6630
• Respiratory Protection addresses protection from the hazards of breathing fumes and gases resulting from such activities.
• The Jefferson Lab Lockout/Tagout procedure, Chapter 6110 Lockout/Tagout, provides administrative controls which minimize the possibility of accidentally penetrating a pressurized fluid system or an electrical system while welding, cutting, or brazing.
• Welding, cutting, or grinding in a confined space presents additional hazards which must be addressed in a confined-space entry procedure. Refer to 6160 Confined Space Entry.

More detailed guidance is given in Appendix 6122-T2 Welding Safety Practices for the following:

• Oxygen-Fuel Gas Welding and Cutting
• Arc Welding and Cutting
• Resistance Welding

Appendix 6122-T1 Use of Fire-Hazard Work Permits (November 28, 1993)

Introduction

This appendix provides direction on the use of a Fire-Hazard Work Permit at Jefferson Lab. Work activities which employ an open flame or produce sparks are restricted and require specific written authorization by means of Fire-Hazard Work Permits or Opera tional Safety Procedures (OSPs).

A Fire-Hazard Work Permit

• is issued by the supervisor of the work, or, in the case of subcontracted activities, the Jefferson Lab inspector or COTR of the work,
• is valid for a specific duration, not exceeding 14 days,
• is required for all fuel-gas welding, cutting, and brazing activities as well as spark-producing grinding and cutting operations unless these activities are covered by an approved Operational Safety Procedure.

Exception: pedestal and stationary grinders mounted in permanent machine shop areas do not require a permit.

Below is the Fire-Hazard Work Permit form. (not reproduced here)

Appendix 6122-T2 Welding Safety Practices (November 28, 1993)

Oxygen-Fuel Gas Welding and Cutting

Arc Welding and Cutting

Resistance Welding

General Precautions

• Sweep floors clear of combustible material. If the floor itself is combustible, cover it with noncombustible material, such as sand, or wet it down. In the latter case, welders must be protected from possible shock by such means as standing on fire resis tant, non-conducting mats.
• Do not cut or weld in sprinkled buildings when the sprinkler system is impaired.
• Do not cut or weld in the presence of explosive atmospheres (gases, vapors, or dusts).
• Do not cut or weld on drums, barrels, tanks, or other containers until they have been thoroughly cleaned and declared free of flammable or combustible materials and gases.
• Use appropriate protective clothing such as face shields, leather gloves, and leather aprons which are designed to prevent burns by protecting skin and clothing from welding slag, sparks, and radiative heat. Face shields must have the appropriate opacity for the type of weld being performed.
• Avoid polyester or nylon clothing; cotton or cotton blend fabric is preferred.