1. School Safety Training
Welding, Cutting and Brazing
WAC Part I

2. Notice
This presentation is provided to all Educational Service District 101 (ESD 101) schools at no cost.
This presentation contains copyrighted materials purchased by ESD 101 for the exclusive use of training school personnel within ESD 101.
This presentation may not be reproduced except to print “handouts” or “notes pages” for use during training within ESD 101 school districts.
If the school district does not have Microsoft’s PowerPoint software available, a PowerPoint viewer can be downloaded from the internet at no cost.
Questions may be directed to the ESD 101 Risk Manager.

3. Compressed Gases
Compressed gases are covered in WAC Part K, but are an integral part of welding, cutting, and brazing
Compressed gas hazards
Gases used for cutting, brazing, and “shielding” the weld
Refer to another ESD 101 program titled “Compressed Gases.”
I. Speaker’s Notes:
Many welding operations will use compressed gases, and therefore, companies must comply with these requirements.
The gases are used for cutting, welding, brazing, and “shielding the weld,” which will be discussed later in this session.
Compressed gas hazards include compressed energy, flammability, asphyxiation, and oxidation.
Refer staff to another ESD 101 School Safety Training program titled “Compressed Gases” for additional details relating to safety of compressed gases.

4. Cylinder Inspection
Most compressed gas cylinders must be periodically tested/ recertified (DOT)
All cylinders contain markings/ symbols that indicate certification status
I. Background for the Trainer:
Show attendees an actual cylinder if one is available.
Point out the certification markings.
II. Speaker’s Notes:
Only DOT-approved cylinders may be used for welding. Most welding supply houses carry only approved cylinders.
According to DOT, these cylinders must be periodically tested and recertified.
You can find the last date of certification by looking for the markings on the cylinder.
An old 5 gallon propane tank from your B-B-Q may not be an approved cylinder.

5. Specific Gases Several of the gases have specific WISHA standards
These gases include acetylene, hydrogen, oxygen, nitrous oxide, ammonia, and LPG
I. Speaker’s Notes:
Fire and explosion are not the only hazards associated with these gases. Some gases can cause adverse health effects.
Gases that are very hazardous are covered under separate WISHA standards. Examples of these gases are listed on the slide.

6. Basic Fire Prevention Fire hazards must be removed, or
Guards installed, or
Welding/cutting must NOT take place
Hot work permit should be used to ensure that all fire hazards are controlled
Use of fire watch
1/2 hour after operation ceases
I. Speaker’s Notes:
Inspection of the welding area should be conducted to avoid possible fires.
It is best to perform welding in a designated area when possible to avoid additional hazards.
If the fire hazard cannot be removed, guards will be installed or the welding/cutting must not take place.
Be sure to obtain a hot work permit before performing any welding jobs. This will help ensure that all hazards are controlled. A permit is not usually required for instruction of students in a vocational program. One might be required if a student or staff member is working on a welding project after-hours.
Someone must also be posted as a fire watch from the time welding begins to one-half hour after the job is done. A fire watch is usually not required during the instruction of students in a vocational program (it is assumed that the instructor is the fire watch – and will be on site for 30 minutes after all welding is completed) A fire watch is required if a student or staff member is working on a welding project after-hours.

7. Fire Prevention (cont.)
Fire extinguishers must be charged/available
Never weld in the presence of explosive atmospheres
Do not weld on used drums, barrels, tanks, or other containers
Test potentially explosive containers for flammable atmospheres
Shut off cylinder valves when they are not in use
I. Speaker’s Notes:
This slide describes additional fire prevention techniques associated with welding.
Make sure that anyone who uses a fire extinguisher has been properly trained.
It may be necessary to inert drums or fill them with water to eliminate flammable/explosive vapors prior to welding or cutting.

8. Protection of Personnel
Keep working surfaces clean and unobstructed
Wear eye protection
Use safety glasses under welding hood
Protective clothing must be used per WAC
Welding in confined spaces
Machines located outside of space
Other confined space precautions apply ( )
I. Background for the Trainer:
Show any available PPE for use while welding (i.e., helmets, gloves, aprons, etc.).
II. Speaker’s Notes:
Face and eye protection is imperative to avoid possible welder’s flash, which can permanently damage your eyesight.
Any welding in a confined space must be monitored to quantify the hazard to the welder and any other space entrants.

9. Oxygen-Fuel Welding WAC 296-24-68221 Acetylene Flammable Unstable
Cannot be piped above 15 psi
I. Speaker’s Notes:
Acetylene is extremely dangerous because of its flammability range.
Oxyacetylene torch cutting is very common throughout the industry as it has a wide flammable range.
Acetylene is extremely unstable.
Acetylene is generated in the cylinder from a reaction of acetone and calcium silicate.
Acetylene must not be piped above 15 psi.

10. Basic Rules for Oxyacetylene Welding
Blow out cylinder valve
Release regulator
Stand to one side of regulator
Open cylinder valve slowly
Not more than 15 psi
I. Speaker’s Notes:
This slide lists basic rules to follow when welding with oxyacetylene.
Before connecting to the regulator, always blow out the cylinder valve.
Release the regulator by adjusting the screw before opening the cylinder valve.
Always stand to the side of the regulator while opening the cylinder in case of accidental pressure release.
Open the valve cautiously and slowly.
Never use acetylene at pressures above 15 pounds per square inch.

11. Basic Rules (cont.) Purge oxygen and acetylene passages
Light the acetylene
Never use oil or grease
Do not use oxygen
Keep your work area clean
I. Speaker’s Notes:
Before lighting the torch, remember to purge acetylene and oxygen passages.
Before opening the oxygen on the torch, light the acetylene.
Never use oil or grease on regulators, tips, or any part that may come into contact with oxygen.
Do not use oxygen as a substitute for air.
Always keep your work area free of items that could ignite.

12. Storage of Fuel Cylinders
Storage area must be well ventilated
Cylinders must be at least 20 feet from combustibles
Valves must be closed
Valve protection must be in place
Inside storage must be limited to 2,000 cubic feet.
Cylinders must be stored in upright position
Oxygen must be at least 20 feet from fuel gas or 5 feet with a 1/2 hour fire barrier
I. Speaker’s Notes:
Valve protection caps are designed to take a blow should the cylinder fall, thus preventing the cylinder from becoming a rocket.
Never lay the cylinder down; store it upright and always secure it during storage.
Regulators should be only on cylinders in use, not on those that are stored.

13. Gas Cylinder Precautions
Never lift cylinders by the service valve or valve protection (use slings, net, etc.)
Keys, handles, hand wheels must be present
Use proper regulator
Open acetylene valve no more than 11/2 turns
I. Speaker’s Notes:
Handling cylinders properly is important because of the extreme pressure they are under. Use these precautions at all times.

14. Protective Devices Pressure relief valves Backflow preventer
Fuel gas hose—red (sometimes black)
Oxygen hose—green
Hose protection required
Pressure-reducing regulators
I. Background for the Trainer:
Show some typical valves, a backflow preventer, and welding hoses to the class.
II. Speaker’s Notes:
These types of safety devices are important to prevent potential fires and/or explosions.
Make sure the system that has been approved remains intact and that high-pressure regulators, etc., are not substituted for approved regulators.

15. Arc Welding Electric current fuses parent metal and welding rod
Indispensable in metal working
Used for carbon and alloy steels and non-ferrous metals
I. Speaker’s Notes:
Arc welding is very common. A high percentage of industrial welding is arc or “stick” welding.

16. Shielding Air must be kept away from weld area
Shielding protects the integrity of the weld joint
Flux or gas mixture is used as a “shield”
I. Speaker’s Notes:
Shielding gases help create a more perfect weld and protect the weld area during the process.
When contaminants enter the weld area, they can create defects, and shielded welding helps prevent this.
“Shielding” is a way to keep air away from the weld.

17. Common Arc Welding Processes
Shielded metal arc welding (stick welding)
Gas metal arc welding (MIG welding)
Gas tungsten arc welding (TIG welding)
Flux cored arc welding
Submerged arc welding
Arc cutting
Plasma arc cutting
I. Background for the Trainer:
As the instructor of this class you ought to be able to explain these various types of welding - at least on a basic level.
II. Speaker’s Notes:
These are the various types of arc welding.
Arc welding such as TIG and MIG use a shielding gas.

18. Installation and Maintenance
Welding machine must be grounded
Work area must be dry and free of hazards
Connections must be tightly made
Splices within 10 feet of holder are prohibited
Cables must be maintained and conductors well insulated
I. Speaker’s Notes:
Follow these straightforward rules for maintaining safe welding equipment.

19. Welding Health Hazards
Zinc
Cadmium
Beryllium
Iron Oxide
Mercury
Lead
Fluorides
Chlorinated hydrocarbon solvents
Phosgene
Carbon monoxide
Ozone
Nitrogen Oxides
I. Speaker’s Notes:
These materials can be liberated during the welding process.
Welding operations should be monitored to see what concentration of these contaminants may be reaching the welder’s breathing zone.
An industrial hygienist should be familiar with the appropriate monitoring techniques for welding fume.

20. Welding Physical Hazards
Ultraviolet radiation
Infrared radiation
Intense visible light
I. Speaker’s Notes:
These hazards are usually handled with eye and face protection as well as welder’s clothing such as aprons and chaps.
Eye and face protection must have certain shades to prevent exposure to welding radiation.

21. Lens Shades for Typical Welding
Welding Process
Shielded metal arc
Gas metal arc
Gas Tungsten arc
Torch brazing
Gas welding
Lens Shade Number
10-14
11-12 12
3 or 4
4-8
I. Background for the Trainer:
Show any welding helmets, glasses, or goggles that may be available.
II. Speaker’s Notes:
Because the shades vary for the different types of welding, it is important that routine inspections be conducted to ensure that the proper shades are used on the various welding operations.
In vocational instruction shops where large screens are placed around the welding area, the proper shade of material must be provided in the screen for the type of welding being performed.

22. Quiz
Fuel cylinders must be stored at least ____ feet from combustibles.
Shielding is a process used to protect the eyes from welding fume. True or False
Three physical welding hazards are ___________ radiation, infrared radiation and intense visible light.
You should not use oxygen as a substitute for air. True or False
As long as they are secure, fuel cylinders can be stored on their side. True or False
I. Background for the Trainer:
Hand out the quiz copies. Go over the questions verbally and have the employees write their answers on their quiz sheets.

23. Quiz (cont.)
Gas Metal Arc Welding is also known as _____________ welding.
Exposure to zinc fumes may cause metal fume fever. True or False
Cylinder inspection requirements are regulated by the Department of__________.
Acetylene has a very narrow flammable range. True or False
Backflow prevention should be provided for oxygen cylinders. True or False

24. Quiz Answers
Fuel cylinders must be stored at least 20 feet from combustibles.
False. Shielding is a process used to keep air away from the weld.
Three physical welding hazards are ultraviolet radiation, infrared radiation, and intense visible light.
True. You should not use oxygen as a substitute for air.
False. Fuel cylinders must always be stored upright.

25. Quiz Answers (cont.)
Gas Metal Arc Welding is also known as MIG welding.
True. Exposure to zinc fumes may cause metal fume fever.
Cylinder inspection requirements are regulated by the Department of Transportation.
False. Acetylene has a very wide flammable range.
True. Backflow prevention should be provided for all oxygen cylinders.