WELDING AND CUTTING SAFETY PROCEDURE

WELDING AND CUTTING SAFETY PROCEDURE

PURPOSE

This Procedure provides safety and health instructions regarding gas and electric welding, cutting, brazing, or similar flame or spark-producing operations to protect personnel and property against heat, evolved gases and fumes, electrical shock, and radiation.

SCOPE

This procedure shall apply to all employees responsible for planning, supervising, and conducting welding and cutting operations.

GENERAL INFORMATION

A.        Supervisors and workers performing welding, cutting, and/or brazing operations shall be trained in hazard recognition, evaluation, and control; fire protection; and safe work practices; and shall adhere to requirements in this procedure.

B.        Welding/Cutting Areas: Whenever possible, welding and/or cutting operations should be performed in areas that are isolated and designated for such uses.  Welding or cutting must not be performed in the following areas:

1.         In the presence of explosive atmospheres;

2.         In areas near the storage of quantities of exposed, ignitable materials;

3.         In sprinklered buildings while such protection is impaired; or,

4.         In areas not authorized by management or by a hot work permit.

C.        Whenever welding operations are interrupted for a substantial period of time (e.g., lunch or overnight) or completed, "hot" metal areas must be identified, and the equipment must be shut off with any valves closed.

D.        Equipment:  Personnel are required to use approved welding, cutting, and grinding equipment and follow the manufacturer’s instructions.  Such equipment shall be maintained in safe working order at all times.  Personnel shall report any equipment defect or safety hazard to a supervisor, and the use of such equipment must be discontinued until it is repaired by qualified personnel.

E.        Site Preparation:  Prior to beginning welding or cutting operations, workers must:

1.         Check the work area (35' radius) to ensure that no fire hazards including oily or greasy materials are present;

2.         Remove all combustible materials within 35’ not necessary for the operation.  Any combustible material that cannot be removed, such as wood platforms, should be covered with a flame-resistant material;

3.         Check that all equipment is in good working condition;

4.         Inform workers in the immediate area and display warning signs at the worksite to alert others of the potential hazards;

5.         Install welding shields/curtains to protect other workers from the sparks and intense light associated with welding/cutting operations; and

6.         When performing welding, cutting, and/or brazing operations in areas on or around Acutely Hazardous Materials which are included in a Process Safety Management (PSM) Program, a hot work permit is required.

F.         Ventilation: Cutting or welding operations must be performed in areas with adequate ventilation to keep fumes and gases within safe limits. 

1.         Local exhaust ventilation must be used when potentially hazardous materials are being worked on.  (Examples of potentially hazardous materials include, but are not limited to, chromium, fluorides, zinc, beryllium, cadmium, lead, and mercury).

2.         Adequate exhaust ventilation must be used when using inert-gas welding, plasma-arc cutting or carbon-arc cutting. 

3.         The metal surface shall be free of all chlorinated solvents during any welding or cutting operations.

G.        Personal Protective Equipment: Approved personal protective equipment (PPE) shall be worn by all employees performing or assisting in welding and/or cutting operations. 

1.         Examples of PPE include eye protection, helmets and hand shields, flame resistant gloves, limb/body protection, and respiratory protection. 

2.         While performing overhead or vertical welding, personnel must wear leather personal protective equipment (shoulder, head, and ear covers). 

3.         All welders should wear flame-resistant aprons, coveralls, gauntlet gloves and shirts with sleeves of sufficient length and construction to protect the arms from heat, UV radiation, and sparks.

4.         Wool and leather clothing are preferred because they are more resistant to deterioration and flame than cotton or synthetics.  Synthetic fiber clothing should not be worn unless it is specifically manufactured to be fire retardant.

5.         Clothing should be kept reasonably free of oil or grease. 

6.         Front pockets and upturned sleeves or cuffs should be prohibited.  Sleeves and collars should be kept buttoned and high boots should be worn under pant legs (or leggings worn) to prevent hot metal slag or sparks from contacting the shin.

7.         Personnel must wear respiratory protection when ventilation is not sufficient to prevent exposure above permissible limits.  (When performing cutting or welding operations involving coatings which generate toxic substances upon heating, or working with materials that contain beryllium, cadmium, lead, or mercury, personnel must wear supplied-air respirators). 

8.         Workers welding on metal alloys should wear work uniforms, coveralls, or similar full-body coverings that are laundered each day.  Lockers or other closed areas should be provided to store work and street clothing separately.

9.         Other personnel in welding/cutting areas not protected by noncombustible or flameproof screens or shields must wear appropriate goggles. 

H.        Confined Space Operations: Proper precautions must be taken by personnel who are required to perform welding or cutting operations in a confined space area.  Refer to the Confined Space Pre-Entry Procedure, and contact the Entry Supervisor prior to performing welding or cutting operations in a confined space.

I.          Prior to welding tanks, cylinders, or other containers, supervisory personnel must complete a hot work permit and shall verify that such containers do not contain, or have not contained, any flammable, toxic, or explosive materials.  If containers have contained flammable, toxic, or explosive materials, they must be emptied, flushed, or otherwise purged and sampled prior to welding. 

J.         Fire Protection: Fire protection equipment must be maintained ready for use at all times that welding or cutting operations are being performed. 

1.         Utility trucks supporting welding/cutting operations must be equipped with fire fighting and fire protection equipment, including a fire extinguisher of at least 10 A:B:C rating. 

2.         If welding is to be performed in areas where a fire hazard may exist, fire watch practices must be established and implemented.  (See Appendix A Hot Work Permit.)

3.         When performing welding or cutting operations on coated surfaces that are highly flammable (determined by a flammability test), the coating must be stripped from the area to prevent ignition.

K.        All surfaces covered with toxic preservatives, including coatings which generate toxic substances upon heating, must be stripped for a distance of at least 4 inches from the area of heat application.

L.         Contractors performing welding and cutting operations must be made aware of the risks involved in the operations, and shall obtain approval from District prior to performing such operations. 

FIRE SUPPRESSION & PROTECTION

A.        Suitable fire protection equipment must be maintained ready for use at all times that welding or cutting operations are being performed.  If welding is to be performed in non-approved areas, supervisory personnel must complete a hot work permit.

B.        A Fire watch and a hot work permit are required when welding or cutting is performed where:

1.         Combustibles are closer than 35' to the point of operation, or where there are appreciable combustibles easily ignited by sparks;

2.         Wall, floor, or other openings within 35' radius that expose combustible materials; or

3.         Combustible materials are adjacent to the opposite side of metal walls, partitions, ceilings, or roofs and are likely to be ignited by conduction or radiation.

C.        If required, duties of the Fire Watch include:

1.         Using fire extinguishing equipment to extinguish fires within the capacity of equipment available;

2.         Sounding an alarm in the event of a fire;

3.         Watching for fires in all exposed areas;

4.         Maintaining a fire watch for at least 1/2 hour (30 minutes) after completion of welding or cutting operations; and

5.         Reporting any injury, including suspected flash burns, to their supervisor.

HOT WORK PERMIT

Prior to performing welding/cutting operations in the following circumstances, a hot work permit must be completed and approved by the appropriate supervisor.

A.        In locations that have not been designated as welding locations.

B.        In confined spaces.

C.        Welding or cutting tanks, cylinders, or other containers.

D.        In areas where a fire hazard may exist (example: weeds, wood products, fabrics, etc).

E.        In areas included in the Process Safety Management Program (if applicable).

F.         In areas where combustibles are closer than 35' to the point of operation.

G.        In areas where combustible materials are adjacent to the opposite side of metal walls, partitions, ceilings, or roofs and areas likely to be ignited by conduction or radiation.

Copies of open permits must be maintained at the job site and in the supervisor’s office. Upon job completion, closed permits should be maintained for three (3) years.

OXY-FUEL WELDING & CUTTING

A.        Prior to beginning welding or cutting operations, workers must check that the cylinders, regulators, backflow prevention device, flame arrestors, hoses, clamps, and torches are in good working condition.

B.        Oil or grease must not come into contact with oxygen cylinders, valves, regulators or other fittings.  Do not handle oxygen cylinders or apparatus with oily hands or gloves, or greasy materials.  Do not let oxygen contact oily or greasy surfaces or clothes, or enter a fuel oil or other storage tank.

C.        Fuel gas and oxidizers must pass through a pressure-reducing regulator prior to being used.  Pressure reducing regulators must only be used at or below the rated pressures and must be specific to the type of gas being used.  Prior to connecting a pressure regulator, cylinder valves should be "cracked" to clear the dust or dirt that might otherwise enter the regulator.  This procedure shall be performed away from other welding work or sparks.

D.        Prior to removing a regulator from a cylinder, personnel must close all cylinder valves, and release the gas from the regulator.

E.        Personnel must follow the manufacturer's operating procedures for lighting the torch.  Generally accepted practices for startup and shut down follow:

1.         Start Up

(a)       Open the oxygen valve on the torch handle and adjust the oxygen regulator to the desired delivery range.

(b)       Close the torch handle oxygen valve.

(c)        Open the fuel valve on the torch handle and adjust the fuel regulator to the required delivery range.

(d)       Close the torch fuel control valve.

(e)       Hold the torch in one hand and the spark lighter in the other.  Open the torch fuel valve approximately one-half turn and ignite the gas.

(f)        Point the torch away from people and combustible materials.

(g)       Keep opening the fuel valve until the flame stops smoking and bring the flame back to the tip.

(h)       Open the torch oxygen valve until a bright neutral flame is reached.

2.         Shut Down

When shutting down the system, first shut off the oxygen, then the fuel gas.  Drain the gas pressures from the system.

F.         Cylinders must be kept far enough away from the actual welding or cutting operation so that sparks, hot slag, or flame will not reach them, or fire-resistant shields must be provided.

CARE OF COMPRESSED GAS CYLINDERS

A.        Compressed gas cylinders shall be legibly marked identifying the contents.

B.        Compressed gas cylinders shall be stored and transported in the following manner:

1.         Valve end must be up.

2.         Outside storage areas must be protected from direct sunlight, external heat sources, electric arcs, or high temperatures.

3.         Inside storage areas must be well-protected, well-ventilated, and in a dry location at least 20 feet from highly combustible materials.

4.         Cylinders containing flammable gases will be stored at least 20 feet from oxygen cylinders.

5.         Cylinders shall not be kept in unventilated enclosures such as lockers and cupboards, or inside the cabs or passenger areas of vehicles.

6.         Valve protection devices must be in place when cylinders are not in use, and during storage and transport.  Valve protection devices must not be used for lifting cylinders.

7.         Cylinders must be prevented from tipping, falling, or rolling.

8.         All empty cylinders will be handled and stored as if they were still pressurized.

C.        If cylinders are found to have leaky valves or fittings which cannot be stopped by closing the valve, the cylinders shall be taken outdoors, away from sources of ignition, and slowly emptied.  Never put other workers at risk.  If the leak is large, do not attempt to move the cylinder, evacuate all personnel from the area and notify your supervisor.

D.        Pressurized cylinders must not be taken into confined spaces.

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Emergency Preparedness

Emergency Preparedness:

“Emergency Preparedness is the discipline of dealing with and avoiding both natural and manmade disasters." It involves mitigation, preparedness, response and recovery in order to lessen the impact of disasters.

Emergency Exit:

A doorway out of a building, which is designated for use in an emergency.

Emergency Evacuation:

Emergency evacuation is the immediate and urgent movement of people away from the threat or actual occurrence of a hazard.

·         Campus Evacuation Procedure

o    When the building fire alarm goes off

ü Evacuate the building immediately

ü Guide any guests and visitors

ü Evacuate through the nearest emergency exit

ü Assemble at the nearest assembly point for headcount

ü Listen to instructions given by Emergency Response Team (ERT) members.

ü Wait until “ALL CLEAR” is given by an ERT member before re-entering the building

ü Site conducts evacuation drills periodically – Be prepared

·         If You Discover a Fire:

ª  Pull down the nearest manual call point, or

ª  Call the Site Emergency Number (----)

ª  Alert other employees in the vicinity

ª  Evacuate the area immediately

ª  Follow the Site Emergency Evacuation Procedures

ª  Roles of Emergency Response Team (ERT) and Floor wardens:

§  Receive training from the ERT Leader, Coordinators and Alternates concerning fire drills, the use of fire extinguishers, the operation of fire alarms, CPR training and other skills or knowledge that may be required in event of an emergency.

§  Assist the ERT Leader, Coordinator and Alternates in responding to an emergency.

§  Acts to respond to emergencies within the limits of their training. The first ERT member to arrive on the scene will be the Emergency Response Coordinator, until relieved by someone of a higher authority.

§  Floor wardens need to maintain a list of disabled persons located in their assigned area and share it with the HSE & HRG team (to ensure proper emergency assistance).

§  Show new staff members the location of fire exits and brief them on emergency evacuation procedures in the event of an emergency evacuation.

§  Ensure all members of assigned area/department are accounted for after evacuation.

§  Communicate with Emergency Response Team Leader/coordinator during an emergency.

Do’s & Don’ts:

Do’s:

ü  Be familiar with emergency evacuation procedure, with the location of area floor plan including emergency exits and stairwell locations.

ü  Know at least two evacuation routes from your office and the nearest assembly point to each;

ü  Get to know your ERT member and follow his/her advice during emergencies;

ü  Identify personnel with special needs or disabilities who may need help for evacuating;

ü  Know where the manual call points are located and how to use them; and

ü  Listen carefully for instructions over the building’s public address system.

Don’ts:

ª  Don’t block fire exits, fire extinguishers or block doorways, or stairways.

ª  Don’t use elevators when evacuating building.

ª  Don’t re-enter the building until directed by authorities.

If trapped during an emergency:

ü  Stay calm and take steps to protect yourself.

ü  Go to a room with an outside window, and telephone for help if possible.

ü  Stay where rescuers can see you and wave a light-colored cloth to attract attention.

ü  Open windows if possible, but be ready to shut them if smoke rushes in.

ü  Stuff clothing, towels, or newspapers around the cracks in doors to prevent smoke from entering your room.

Posted by Department of Occupational Safety & Health Training Institute

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USE OF AIR WINCH PROCESS

 USE OF AIR WINCH PROCESS

What is an Air Winch?

An air winch, also known as an air tugger or air hoist, is a powerful, air-powered machine used for the lifting, pulling, suspension, and tensioning of materials. When properly rated, they can also move personnel between decks, floors, and other areas. In the oil and gas, construction, and maritime industries, air winches are frequently preferred to electric, diesel, and hydraulic winches because of their durability, versatility, and safety.

When Should I Use an Air Winch?

Air winches can fit into spaces and move materials in areas that are unreachable by crane. They are also suitable for areas where fire hazards exist. They have no electrical parts to cause a shock risk, and are fueled by air instead of flammable fuel. Air motors cannot burn out, and can be stalled for long periods without damage. This makes air winches ideal for suspending and tensioning materials. Despite these inherent safety features, they can still pose hazards if safety procedures are not followed properly.

How Do I Choose an Air Winch?

In selecting a specific type of air winch, you should consider job location, the weight and type of load to be moved, mounting site, and wire rope. Follow jurisdictional and company regulations for every particular jobsite. Consider the load as each air winch has a maximum load capacity, known as a maximum rated capacity, which can never be exceeded.

Air winches are categorized as utility, personnel, or dual-rated. Utility winches are rated to move material. Personnel winches, also known as man-riders, are rated to lift, lower, or suspend personnel. Dual-rated winches are rated for both material and personnel, but once used for one of these applications, must exclusively handle that type of load.

What are the Characteristics of a Wire Rope?

The wire rope used by an air winch is comprised of three basic components. First, steel wires form the strands of the wire. Second are the strands themselves, which spiral around the core. Third is the core, which serves as a foundation for the strands.

There are also six characteristics of wire rope:

Size refers to the diameter of the rope, and is always measured at the rope's widest point.

Classification is given as two numbers, representing the strand and wire count. An example would be 6x37, which refers to a rope with 6 strands each made up of 37 wires. Higher wire and strand counts produce more flexible, but less durable ropes.

Rope Lay describes the direction that the wires and strands spiral around the core.

The Grade of Steel of a wire rope will be one of three types: Improved Plow Steel (IPS), Extra Improved Plow Steel (EIPS or XPIS), which is the most commonly used and manufactured grade, or Extra Extra Improved Plow Steel (EEIPS or XXIPS).

There are also three different options for the Type of Core. Fiber core (FC) is made of synthetic material, is the most flexible and elastic, but is susceptible to crushing. Wire strand core (WSC) is made up of an additional strand of wire, is used in smaller ropes, and is ideal for suspension and tensioning. Independent Wire Rope Core (IWRC) contains a smaller wire rope to serve as the core, is highly durable in all environments, and is preferred in offshore and construction environments.

Finally, the nominal strength describes the minimum breaking strength of a new, unused rope.

How Do Air Winches Operate?

Air winches operate using compressed air, usually measured in pounds per square inch gauge, or PSIG. When choosing an air compressor, ensure that its output is compatible with the requirements of the winch. The air compressor's output must equal the winch's air consumption for continuous winch operations.

Most air winches are rated for 90 PSIG inlet pressure when the winch is running. The volume of air required for winch operation is expressed in cubic feet per minute (CFM) or cubic meters per minute (m³/min).

All hoses and fittings must also be compatible with the winch.

How do you Mount / Install an Air Winch?

The mounting site for the winch must be a firm foundation, such as steel support beams, that can withstand five times the maximum load rating of the winch. The mounting site should be as level as possible.

The winch should have a support frame that can be secured to the foundation with heavy bolts or welds. If not, a frame must be attached. Always use the mounting bolts designed for the winch. Never use screws to hold a winch in place. If welding a winch in place, ensure all hot work is done by a qualified welder.

Position the winch so that the operator will have easy access to the hand controls, is always facing the load, and will never be positioned between the load and the winch.

Winch operations should never interfere with other jobs, or be stationed in areas where objects could fall and either injure the operator or damage the winch. Plan the load path so that the load does not travel over, or near, other personnel, workstations, or walkways. In situations where the load must travel over these areas, barricade the load path and post a watch to prevent entry until operations conclude.

Position the airline so that it does not create a tripping hazard, and also label the line so that it is not accidentally disconnected during use.

What is the D/d Ratio and How is it Calculated?

Normal wear occurs each time the rope is used as the wire rope bends around the winch drum or a sheave. The D-to-d ratio accounts for this wear and indicates if a wire rope will be excessively worn or damaged during normal operations. This ratio simply compares the winch drum diameter to the rope diameter.

The D-to-d ratio is calculated by adding the winch drum diameter (D) to the wire rope's size (d) and then dividing the sum by the wire rope size (d).

(D + d)

------

d

For example, if a winch has a 24 inch (D) drum diameter and a 1 inch (d) wire rope is used, the ratio is 25:1.

Higher D-to-d ratios put less stress on the rope. D-to-d ratios which are too low will over-stress and put excessive wear on the rope.

The minimum D-to-d ratio for lifting or lowering a load is 18:1, and the minimum recommended D-to-d ratio for moving personnel is 22:1.

What Are The Steps to Safe Winch Operation?

Safe winch operation helps protect not only those directly involved, but all those at the worksite. Safely operating an air winch can be summarized by completing four simple steps.

The first step of safe winch operation is performing a job safety analysis, or JSA, and obtaining a work permit, if necessary, before the job. A JSA identifies the potential hazards of each winch operation, and then introduces steps to eliminate or reduce these hazards to an acceptable risk level.

The second step of safe winch operation is inspecting the winch and wire rope at the correct intervals. If the winch or wire rope fail any aspect of an inspection, they should not be used.

The third step of safe winch operation is following safe operating guidelines before, during, and after each operation.

The fourth step in safe winch operation is proper winch maintenance performed by authorized personnel. Maintenance helps prolong the life of the winch and helps prevent accidents from occurring.

What are Common Safe Operation Winch Guidelines?

Always ensure that all safe operation guidelines are observed during winch operations.

Common safety rules include:

·         Winch operators must always be qualified and trained

·         Before operations begin, verify that the signal person is visible at all times

·         The operator must focus on the environment and load

·         Ensuring the load never passes near or over personnel or workstations

·         All personnel must stay clear of moving loads at all times

·         Use barricades or designated personnel to prevent entry into the area

·         Only the signal person may relay commands to the operator

·         Anyone may give the emergency stop signal to the operator

How Do You Inspect a Winch?

Performing and documenting regular inspections can uncover problems before a serious accident occurs. If the winch or wire rope fails any aspect of an inspection, they must not be used.

Examine all control mechanisms for any indications of damage or excessive wear.

Inspect all limit switches or limiting devices each shift to ensure they are working properly.

Check for any deterioration or leakage in the compressed air system, including all connections and fittings.

The frequency with which wire ropes should be inspected also depends on the work environment, manner, and how often they are used.

Wire ropes in continuous service must be inspected before the first use, before each shift, or more frequently, depending on work conditions and past experience. To properly inspect wire rope it must be un-reeled.

Check all load attaching equipment and rigging for damage, and ensure the work area is clear and free of debris.

Once all components have passed the inspection, carefully re-spool the rope around the drum. Winch operations can now begin.

Post by Indian Safety Association 

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