Burning, welding, and brazing or cutting are collectively referred to as hot work. Hot work is any work which may generate heat, flame, or sparks (Welding, Cutting, Brazing, Grinding). Hot work presents many dangers and hazards if it is not undertaken with great care and good safety practices.

The purpose of this training is to advise you of the hazards and safety practices of hot work so that you can work safely.

Definitions

• Who is a welder?

According to OSHA, a welder is anyone who operates welding and cutting equipment whether gas or electric.

• What are the types of welding?

Gas Welding, Arc Welding, and Oxygen and Arc Cutting.

• What is approved welding equipment?

Only standard electric arc welding equipment such as generators, motor generator units, transformers, etc., conforming to the requirements of the National Electrical Manufacturers Association or the Underwriters Laboratory, Inc., or both, should be used.

• Permit Authorizing Individual(s) (PAI): In conjunction with management, responsible for the safe operation of Hot Work activities. There shall be two PAIs established per complex. PAIs on the SUU campus are the Campus Fire Marshals.

• Hot Work Operator (HWO): This includes outside contractors: The individual responsible for completing the hot work, under the direction of the PAI(s). 

• Fire Watch: Individual assigned to watch the area for sparks, or any other unsafe conditions. The person doing the hot work should never be the fire watch. The only focus of this person shall be fire watch.

• Designated Area: An area where hot work may be performed without the need for a permit to be assigned. All designated areas must be designated by and pass a quarterly review by the campus Permit Authorizing Individual.

Hazards

Hot work presents many risks and hazards. These include:

• High Temperatures and sparks that can cause fires and burns

• Chemicals and fumes that may contribute to fires, explosions, and poisoning

• Intense radiation which can lead to burns and eye damage

• Electrical exposure that can shock, burn, and even kill

• Loud sounds that could cause hearing damage

• Mechanical failures that may cause various injuries

• etc.

Because there are so many dangers involved, it is important for you to know and understand SUU’s welding safety policies and procedures.

The Campus Fire Marshal is part of Facilities Management. This position is concerned with issues related to fire safety and acts as liaison with state and local fire officials. The Fire Marshal must be consulted before beginning any work or activity that may trigger the fire alarms unnecessarily. This way the Fire Marshal can enact an appropriate Fire Alarm Shutdown Procedure. To contact the Fire Marshal, or for more information about fire safety, see https://www.suu.edu/erm/fire-marshal.html.

Given direction from the Department of Facilities and Construction Management and State Risk Management, Southern Utah University has established a new (2023) hot work permit on campus. The following must be considered prior to beginning any hot work on campus.

Please note that hot work permit requirements are subject to change per campus fire marshal and state regulations.

Other considerations:

Hot Work Checklist

1. Has the area been approved for hot work by the campus Fire Marshal?

2. Has equipment been inspected and found to be serviceable prior to use?

3. Are sprinklers in service, where provided?

4. Have flammable liquids been removed from the work area?

5. Have combustible or hazardous materials been relocated at least 35 feet from the operation? Have combustible materials that cannot be removed been covered with fire-resistive tarpaulins?

6. Have floor and wall openings within 35 feet of the operation been tightly covered?

7. Have screens or shields been erected to protect pedestrians from the welder’s arc?

8. Has the atmosphere been tested for the presence of flammable gasses or vapors?

9. Do all workers have personal protective equipment (PPE) appropriate for their tasks?

10. Are ample fire extinguishers available?

11. Has a fire watch been provided during work, breaks, and for at least 30 minutes after work is complete?

Preparing the Work Area

Areas where hot work is done should be properly designated and prepared. Combustible and flammable materials within the work area should be protected against fire hazards and the operation should not pose a hazard to others in nearby areas. To help achieve this, the following controls should be used:

• Welding and brazing operations are performed only by authorized, properly trained individuals;

• If possible, hot work must be performed in a properly designed shop area equipped with all necessary controls and adequate ventilation;

• Move combustible materials at least 35 feet from the work site. If this is not possible, protect combustible materials with metal guards or by flameproof curtains or covers (other than ordinary tarpaulins);

• Cover floor and wall openings within 35 feet of the work site to prevent hot sparks from entering walls or falling beneath floors or to a lower level;

• Fire resistant curtains and/or tinted shields must be used to prevent fire, employee burns, and ultraviolet light exposure.

PPE

Eye, face, hand/arm, head and body protection (leather gloves, leather apron, gauntlets, safety glasses with side shields, welders helmet or welders goggles) appropriate to the potential hazards encountered during welding, cutting, brazing, soldering, grinding or other spark producing operations are required by SUU and state regulations

A table for choosing the right eye protection can be found on the ERM website under Welding & Brazing PPE.

Chemical Hazards

Welding is a job that requires working with many metals and the dangerous chemicals that they can produce. For example, Zinc is a metal used as a coating on some products to protect from damage. Inhalation of zinc oxide fumes can occur while welding and causes metal fume fever. While the symptoms tend to last no longer than 24hrs, this is one example of a common chemical hazard. Other harmful metals frequently used by welders include:

1. Cadmium

2. Beryllium

3. Fluorides

4. Phosgene (must be well away from any operation in which ultraviolet radiation or intense heat is generated)

Physical Hazards

There are some physical hazards that accompany hot work that can cause injury that you may not notice until after work. These include:

1. Ultraviolet radiation - Can cause burns and eye damage

2. Infrared radiation - Can cause burns

3. Intense visible light - Can cause eye damage

Once you have finished hot work, you still have work to do. Your project and equipment may still be hot, so don't let your guard down.

Keep a fire watch for at least half an hour afterward. This will prevent fires, accidents, and burns.

When it has cooled to a safe temperature, put away welding equipment to prevent accidents and to keep the equipment in good condition.

Acetylene Gas Welding

An oxyacetylene welding outfit is basically made up of: cylinders of oxygen and acetylene, regulators, hoses, and a torch.

Oxygen and Acetylene are stored in separate cylinders in a high pressure, which is controlled by the regulators.

Hoses carry the gasses from the cylinders to the torch. The green hose carries Oxygen. The red Hose carries Acetylene.

The gasses are mixed inside the torch. When burned they produce a very hot flame. The flame is regulated by interchangeable torch tips and by the torch valves. 

Under no condition shall acetylene be generated or utilized at a pressure in excess of 15 psig.

Using acetylene at a pressure in excess of 15 psig is a hazardous practice. Free gaseous acetylene is potentially unstable at pressure above 15 psig and could decompose with explosive violence. 

The decomposition characteristics of acetylene gas are avoided by keeping the gas in liquid solution and storing it in cylinders of unique construction.

Arc Welding

1. Arc rays produce intense visible and invisible (UV and IR) rays that can burn eyes and skin.

2. Any exposed skin can be burned quickly by these rays (Flame resistant clothing).

3. Approved safety helmet with a proper filter shade should be used.

4. Shields and barriers to protect others.

5. Operators should never store matches or lighters in their pockets.

6. The use of chlorinated solvents shall be kept at a distance of at least 200 feet, unless shielded.

7. Wet working conditions must be avoided because water is an excellent conductor and electricity will always follow the path of least resistance.

Ventilation

Mechanical ventilation is required in any of the following conditions: 

1. When working with metals that can produce toxic gasses

2. When working in spaces less than 10,000 cubic feet or 284 cubic meters

3. When ceiling height is less than 16 feet or 5 meters.

In any of these conditions the minimum ventilation rate is 2000 cubic feet or 57 cubic meters per minute per welder.

Things to Remember

1. Be sure the welder is properly installed and grounded.

2. Never weld without adequate mechanical ventilation. 

3. Take proper precautions to prevent fires.

4. Protect your entire body with fire-retardant clothing, shoes, and gloves.

5. Wear eye protection at all times.

6. Weld only in fire-safe areas.

7. Never do any welding, cutting, or hot work on used drum barrels, tanks, or other containers.