1. Introduction to Welding
Mr. Byron
All images acquired from weldingteacher.com

2. Welding
Welding joins two pieces of metal by the use of heat, pressure, or both
Brazing or soldering involves a filler metal which has a lower melting point than the metal pieces to be joined
Metal cutting is done by heating the metal with a flame and directing a stream of pure oxygen along the line to be cut
Coalescence: to cause to unite into one mass

3. Weld A homogeneous bond between 2 pieces of metal
The strength of the welded joint exceeds or equals the strength of the original base metal

4. Types of Welding Arc Welding Shielded Metal Arc Welding (SMAW)
Metal Inert Gas (MIG)
Tungsten Inert Gas (TIG)
Plaza Arc Welding (PAW)
Submerged Arc Welding (SAW)
And Many More…..more than 80 in all

5. The Weldment

13. All information acquired from Sheridan College
Welding Safety
All information acquired from Sheridan College

14. Health Hazards Gases and Fumes…
Welding “Smoke” is a mixture of very fine particles called fumes and gases
Welding “Smoke” contains fumes and gases including…
Chromium, nickel, arsenic, asbestos, manganese, silica, beryllium, cadmium, nitrogen oxides, phosgene, acrolein, fluorine compounds, carbon monoxide, cobalt, copper, lead, ozone, selenium, and zinc

15. Gases and Fumes Generally, gases and fumes come from…
Base material & filler material
Coatings & paints
Shielding gases & chemical reactions
Process & consumables used
Contaminants in the air

16. It is difficult to list all the health effects of welding exposures because the fumes may contain so many different substances that are known to be harmful
The individual components of welding “smoke” can affect just about any part of the body, including the lungs, heart, kidneys, & central nervous system

17. Exposure to welding “smoke” may have…
Short-term effects…
Effects happen at or very soon after exposure
Long-term effects
Effects may happen after repeated overexposures or an extended time after the exposure

18. Short-term Exposures
Exposure to zinc, magnesium, copper and copper oxide can cause Metal Fume Fever
Symptoms of metal fume fever may occur 4 to 12 hours after exposure
Symptoms include…
Chills, thirst, fever, muscle ache, chest soreness, coughing, wheezing, fatigue, nausea, and metallic taste in mouth

19. Short-term Exposures
Welding “smoke” can irritate the eyes, nose, chest and respiratory tract
Welding “smoke” can cause coughing, wheezing, shortness of breath, bronchitis, pulmonary edema, and pneumonitis
Welding “smoke” can cause nausea, loss of appetite, vomiting, cramps, and slow digestion

20. Short-term Exposures Exposure to cadmium can be fatal in a short time
Ultraviolet radiation can react with oxygen and nitrogen to form ozone and nitrogen oxides
These gases are deadly at high concentrations and can also cause irritation of nose and throat and cause serious lung disease

21. Short-term Exposures
Ultraviolet rays given off by welding can react with hydrocarbon solvents such as…
Trichloroethylene; 1,1,1-trichloroethane; methylene chloride; & perchloroethylene to form phosgene gas
Even a very small amount of phosgene gas may be deadly
Early symptoms include dizziness, chills, and cough and usually take 5 – 6 hours to appear

22. Short-term Exposures
Arc welding should never be performed within 200 feet of degreasing equipment or solvents

23. Long-term Exposures
Studies of welders, flame cutters, and burners have shown that welders have an increased risk of lung cancer…
and…possibly cancer of the larynx and urinary tract
Remember… welding “smoke” can include cancer causing agents such as…cadmium, nickel, beryllium, chromium, and arsenic

24. Long-term Exposures
Welders may experience a variety of chronic respiratory problems, including…
Bronchitis, asthma, pneumonia, emphysema, pneumoconiosis, decreased lung capacity, silicosis, and siderosis

25. Long-term Exposures Other health problems…
Heart disease, skin diseases, hearing loss, chronic gastritis, gastroduodentis, and ulcers of the stomach and small intestine
Reproductive risks

26. Other Health Risks Heat exposure…
Heat stress, heat stroke
Burns, eye injuries from hot slag, metal chips, sparks, and hot electrodes

27. Other Health Risks
Visible light, and ultraviolet and infrared radiation
Intense light can cause damage to retina
Infrared radiation may damage the cornea and result in cataracts
Invisible UV light can cause “arc eye” or “welders’ flash”
May include sandy or gritty eye, blurred vision, intense pain, tearing, burning and headache

28. Health Risks cont. Permanent eye damage Skin burns Skin cancer Noise
Can result in stress, increased blood pressure, may contribute to heart disease, tiredness, nervousness, and irritability

29. Musculoskeletal Injuries
Back injuries, shoulder pain, tendonitis, reduced muscle strength, carpal tunnel syndrome, white finger, and knee joint diseases
Injuries may be caused by overhead work, vibration and heavy lifting

30. Electrical Hazards
Even though welding generally uses low voltage, there is still a danger of electric shock
Wet work areas, Cramped work spaces
Falls, fractures and other accidents can result from electrical exposure
Even small shock can cause brain damage
Death can occur from large shocks

31. Electrical Hazards Always use dry gloves
Always wear rubber soled shoes
Always use insulating layers
Protect yourself from surfaces that conduct electricity
When working on electrically powered machinery, make sure the frame is grounded
Keep insulation on all welding equipment and components dry and in good condition
Don’t change electrodes with bare hands, wet gloves or while standing on wet or ungrounded surfaces

32. Fire and Explosion Hazards
Intense heat and sparks can cause fires or explosions if in the vicinity of combustible or flammable materials
Welding and cutting should only be performed in areas free of combustible materials such as trash, wood, paper, textiles, plastics, chemicals, and flammable dusts, liquids and gases

33. Fire and Explosion Hazards
Never weld or cut on containers that have held a flammable or combustible material unless the container is thoroughly cleaned or filled with an inert gas
A fire inspection should be performed prior to leaving a work area and for at least 30 minutes after the operation is completed
Fire extinguishers should be nearby, of proper size, type and number for the hazards involved

34. Dangerous Machinery
All machines in the area with moving parts must be guarded to prevent worker’s contact
Hair, clothing, fingers, etc.
When repairing machinery by brazing and welding, power must be disconnected, locked out, and tagged so the machinery cannot be started up accidently

35. Trips and Falls To prevent trips and falls…
keep work areas clear of equipment, machines, cables, and hoses
Always properly maintain and use handrails
Always use and maintain safety lines, harnesses and lanyards
Always make sure that scaffolds are properly assembled and used

36. Welding Hazards
Never weld or cut in explosive, flammable, combustible or other dangerous environments
Always use all necessary Personal Protective Equipment (PPE), including, harness and lanyard, respiratory protection, eye protection, etc.

37. Compressed Gas Hazards
Gas welding and cutting use a fuel gas and oxygen which are stored in high pressure cylinders
Most fuel gases are explosive
Pure oxygen will increase the flammability of any combustible/flammable material

38. Compressed Gas Hazards
All cylinders should have caps or regulators
Pressure regulators must be designed for gas in use
Check all equipment and components prior to use
Cylinders must be stored upright and secured
Oxygen and fuel gas cylinders must be stored separately
Be aware of flashbacks and backfires
Close cylinder valves when work is completed or left unattended during breaks, etc.

39. Protective Clothing Fire resistant gauntlet gloves Head cap
High top hard toed shoes
Leather apron
Face shield
Flame retardant clothing
Safety Glasses

40. Hearing Protectors
Ear plugs and/or muffs should be worn during noisy operations such as air arcing or grinding

41. Work Cited
Welding Teacher.com. N.p.. Web. 20 Aug WY MSHA State Grant Program, . "Welding Safety.“ Sheridan College. N.p.. Web. 24 Aug 2014.