Welding Safety Level 1 chapter 1 Objectives When

Welding Safety Level 1 – chapter 1

Objectives When we have completed this chapter, you will be able to : Identify common hazards in welding Explain and identify personal protection equipment Identify and explain material safety data sheets Demonstrate proper material handling methods

2. 0. 0 Welding Safety Practices � Many hazards are associated with welding and cutting. � Some of these hazards are: � Electric shock � Infrared rays � Ultraviolet rays (UV) � Hot metal � Slag & sparks � Welding fumes � It is necessary that personnel new to welding understand the hazards of welding and develop the proper attitude toward safety � The welding industry is fortunate to have a well developed standard for safety: ANSI Z 49. 1 -2005, Safety in Welding, Cutting and Allied Process

2. 0. 0 Welding Safety Practices There are many causes of accidents. They can usually be divided into two broad categories: Personal Physical

2. 1. 0 Personal Factors that Cause Accidents can often be traced to personal factors such as: Poor health Lack of experience Improper use of medications Alcohol abuse Mental stress

2. 1. 0 Personal Factors that Cause Accidents �As a worker, you need to be able to recognize when others may not be up to par and take appropriate precautions. �Age and inexperience often play a role in accidents. � In fact, insurance company statistics show that more accidents occur in the under 18 age group than in any other. �Alcohol and drugs affect coordination, alertness, and decision-making ability. �Never use these substances while you are working, and don’t work with people who use them.

2. 2. 0 Physical Factors that Cause Accidents are often caused by conditions at the job site.

2. 2. 0 Physical Factors that Cause Accidents Conditions that affect safety at a work site: Vehicle traffic and foot traffic increases at starting and quitting times. Cleanliness of work site Tools and scrap laying in walk paths Damaged tool and equipment

3. 0. 0 Appropriate Personal Protective Equipment (PPE) Depending on the job and conditions, PPE can include: Body protection Foot protection Hand protection Ear protection Eye, face and head protection

3. 1. 0 Body Protection Basic clothing should offer protection from flying sparks, heat, and ultraviolet radiation from welding. Shirts should be made of a tight weave fabric, have long sleeves and pocket flaps Pants should fit properly and not bunch around the feet Never wear polyester or other synthetic fibers Sparks will melt these materials causing serious burns Wear cotton which is more resistant to sparks Never wear permanent press clothes

3. 1. 0 Body Protection For cutting operations and out-of-position welding, additional protection is needed. Protective coverings made of leather is best because its durability. A full leather jacket offers the most protection but is hot and heavy. A cape is cooler but offers only shoulders , chest and arm protection.

3. 1. 0 Body Protection

3. 2. 0 Foot Protection OSH A requires that protective footwear be worn when working where falling, rolling, or sharp objects pose a danger of a foot injury. High-top safety shoes or boots (steel toe) 8” or taller should be worn Sneakers, tennis shoes or similar types of footwear must never be worn on the job site or weld shop.

3. 3. 0 Hand Protection Gloves are the primary type of hand protection. Gloves must be selected on the basis of the hazards involved in doing the work. Gauntlet-type welding gloves must be worn when welding or cutting to protect against heat and UV rays.

3. 4. 0 Ear Protection If overhead work is being performed, hot sparks can cause burns to the ears and ear canal. Disposable ear plugs are the most common form of hearing protection used in the industry. (on first-aid box in front of shop) For maximum protection, earmuff-type hearing protection should be worn. Plain cotton placed in the ear is not an acceptable hear protection

3. 5. 0 Eye, Face, and Head Protection � The heat and light produced by cutting and welding operations can damage the skin and eyes. � Welding operations involving an electric arc of any kind produce UV radiation which can cause severe burns to the eyes and exposed skin. � Never look directly at the welding arc, this can cause a flash burn. � A flash burn can harm unprotected eyes in just seconds. � The risk of flash burn can be reduced by wearing safety glasses with a properly tinted lens � A flash burn cause permanent damage to the retina.

3. 5. 0 Eye, Face, and Head Protection For electric welding operations wear a welding helmet with a properly tinted lens (shade #9 - #14) must be worn over safety glasses to provide proper protection.

4. 0. 0 Ventilation � Adequate ventilation should be provided to remove fumes that are produced by welding and cutting processes. � There are three methods of ventilation: � Natural ventilation � Mechanical ventilation – fixed or portable fans � Source extraction – uses a mechanical device to capture welding fumes at or near the arc. � The following general rules should be followed in welding areas: � There must be air circulation � Partitions and equipment should not block air circulation

4. 0. 0 Ventilation � Welding or cutting processes create fumes � Fume plum is the term used to describe the fumes, gases, and particles created by the welding process. � Fumes are solid particles consisting of the base metal, electrode or welding wire, and any coatings applied to them. � Some consumables and base metals contain toxic materials that require special ventilation. � These are: � Cadmium � Chromium � Copper � Zinc

4. 2. 0 Respirators Special metals require the use of respirators to protect welders from harmful fumes. Respirators are grouped into three main types: Air-purifying respirators Supplied-air respirators Self-contained breathing apparatus

4. 2. 1 Air-Purifying Respirators Air-purifying respirators provide the lowest level of protection. They are made for use only in atmospheres that have enough oxygen to sustain life (at least 19. 5%). Air-purifying respirators use filters and cartridges to remove gases, vapors, and particles from the air. The cartridges need to be changed when the wearer detects any taste or smell.

4. 2. 2 Supplied-Air Respirators Supplied –air respirators provide a supply of air for extended periods of time via a high pressure hose that is connected to an external source of air, such as a compressed air cylinder or pump. They provide a higher level of protection in atmospheres where air purifying respirators are not adequate. Supplied air respirators are typically used in toxic atmospheres.

4. 2. 2 Supplied-Air Respirators Some supplied air respirators can be used in atmospheres that are immediately dangerous to life and health (IDLH). An atmosphere is considered IDLH if it poses an immediate hazard to life or produces immediate, irreversible and debilitating effects on health. There are two types of supplied air respirators: Continuous-flow Pressure demand

4. 2. 2 Supplied-Air Respirators The continuous flow supplies air respirator provides air to the user in a constant stream. Continuous flow respirators are made with tight fitting half mask or full face pieces. Pressure demand respirators supply air to the user’s face piece via a pressure demand valve , as the user inhales, fresh air is supplied.

4. 2. 3 Self-Contained Breathing Apparatus (SCBA) SCBA provides the highest level of respiratory protection. They can be used in oxygen deficient atmospheres (below 19. 5%), in poorly ventilated or confined spaces, and in IDLH atmospheres. These respirators provide a supply of air for 30 -60 minutes.

Break Time 15 minute break

4. 3. 0 Respiratory Program �A respirator must be properly selected (based on the contaminant present and its concentration level), properly fitted, and used in accordance with the manufacturer’s instructions. �As an employee, you are responsible for wearing respiratory protection when needed. �If, while working in an area that requires a respiratory, your breathing becomes difficult, you become dizzy or nauseated or if you smell or taste the chemical, leave the area immediately. �Go to fresh air and seek medical assistance.

4. 3. 1 Positive and Negative Fit Checks All respirators are useless unless properly fit-tested to each individual. To obtain the best protection from your respirator, you must perform positive and negative fit checks each time you wear it. The fit test steps are on pg. 1. 17.

5. 0. 0 Confined Space Permits � A confined space refers to a relatively small or restricted space, such as a storage tank, or small compartment. � OSHA defines a confined space as a space that: � Is large enough and so configured that an employee can bodily enter and perform assigned work. � Has a limited or restricted means of entry or exit � Is not designed for continuous employee occupancy � For safe working conditions, the oxygen level in a confined space atmosphere must range between 19. 5% and 23. 5%. � Oxygen concentrations below 19. 5% are considered deficient.

6. 0. 0 Area Safety An important factor in area safety is good housekeeping. The work area should be picked up and swept clean. It is important to keep flammable liquids as well as rags , wood, and other combustibles out of the weld area. Have a fire extinguisher nearby.

6. 0. 0 Area Safety If a piece of hot metal must be left unattended, use soapstone to write the word HOT on it before leaving the piece. Whenever welding must be done outside a weld booth, use portable screens to protect other personnel from the arc or reflected glare. The portable screen also prevent drafts of air from interfering with the stability of the arc. The most common welding accident is burned hands and arms.

7. 0. 0 Hot Work Permits and Fire Watch � A hot work permit is an official authorization from the site manager to perform work that may pose a fire hazard. � The permit includes the following: � Time � Location � Type of work being done � A fire watch is required during hot work operations. � A fire watch is a person other than the welder or cutting operator that constantly scans the area for fires. � Cutting operations must never be performed without a fire watch. � When hot work permit rules are violated, severe penalties are imposed, usually termination.

8. 0. 0 Oxyfuel Gas Welding and Cutting Safety Most welding environment fires occur during oxyfuel gas welding and cutting. Welders should be trained in methods for starting, testing for leaks, and shutting down oxyfuel equipment.

9. 0. 0 Cutting Containers must be cleaned by steam cleaning, flushing , or washing with soap. After cleaning the container, fill it with water or an inert gas such as argon or CO 2 to displace the explosive fumes. Never weld or cut on a container that does not have a vent. Welding or cutting on a containers that does not have a vent will cause the container to explode. Never weld on a tire rim with an inflated tire still on it.

10. 0. 0 Cylinder Storage and handling �Oxygen and fuel gas cylinders must be stored separately. �The storage areas must be separated by 20’ or by a wall 5’ high with at least a 30 -minute burn rating. �Inert gas cylinders can be stored with either oxygen or fuel gas cylinders. �Empty cylinders must be stored separately from fulls. �Cylinders must be stored vertically and have protective caps screwed on tightly. �Cylinders must be secured with a chain or other device so they cannot be knocked over accidently.

10. 0. 0 Cylinder Storage and handling

10. 4. 0 General Precautions Any cylinder that leaks , has a bad valve, or has damaged threads must be identified and reported to the supervisor. In its gaseous form, acetylene is extremely unstable and explodes easily. For this reason it must remain at pressures below 15 pounds per square inch (psi).

10. 4. 0 General Precautions � If liquid acetone is withdrawn from a cylinder, it will gum the safety check valves and regulators and decrease the stability of the acetylene stored in the cylinder. � For this reason, acetylene must never be withdrawn at a per-hour rate that exceeds 1/7 th of the volume of the cylinder. � Acetylene cylinders in use should be opened no more than 1 ½ turns. � If a acetylene cylinder is tipped over, stand it upright and wait at least one hour before using it. � Keep cylinders in the upright position and securely chained to an undercarriage or fixed support

11. 0. 0 Power Tool Safety All power tools must be properly grounded to prevent accidental electric shock. If you feel even a slight tingle while using a power tool, stop and have the tool checked by a technician. If an extension cord is used, it should be large enough to carry the proper amount of current for the tool. If the extension cord is too small, the tool and cord will overheat.

12. 0. 0 Electrical Safety Electrical shock from welding and cutting equipment can kill or cause severe burns by coming in contact with bare skin. The amount of current that passes through the human body determines the outcome of an electric shock. The higher the voltage the greater the chance for a fatal shock. Note that the potential for shock increases dramatically if the skin is damp.

12. 0. 0 Electrical Safety The following is a guide to the results of an electric shock by the amps : Greater than 3 milliamps (m. A)- indirect accident Greater than 10 m. A – muscle contraction Greater than 30 m. A – lung paralysis, usually temporary Greater than 50 m. A – possible heart attack 100 m. A – to 4 A – certain heart attack Greater than 4 A – heart paralysis, severe burns

13. 0. 0 Material Safety Data Sheet All manufactures of potentially hazardous material must provide detailed information regarding possible hazards resulting from the use of their product in the form of a material safety data sheet. All MSDS sheets must contain the same basic information on at least nine required sections. The manufacturer must put the company name, address, phone number, chemical name of product, dangers associated with the product, fire hazards, reactivity, and first aid procedures.

14. 1. 0 Lifting When lifting heavy objects, distribute the weight of the object evenly between both hands. Use your legs, not your back. Do not try to lift a large or bulky object without help.

14. 2. 0 Hoists or Cranes Check the capacity of the equipment before trying to lift a load. Keep any load as close to the ground as possible while it is being moved. Pushing a load on a crane is better than pulling a load. When moving or lifting a load with ropes, chains, and cables, stand to one side of the load to prevent injury if the equipment or material should shift or fall.

Summary Safety is everyone’s responsibility. The job site should always be evaluated to revel any hazards. (15. 0. 0 Safety Planning) Proper clothing, footwear, and eye protection are essential for safe welding. Workers who fail to comply with safety rules are subject to dismissal. Review questions 1 – 15 Trade terms quiz 1 -6 (pg. 1. 34)