Power Tools Safety – Types, Hazards & Precautions
POWER TOOLS SAFETY
PORTABLE POWER TOOLS
Portable power tools are divided into five primary groups according to their power source, which are electrical, pneumatic, gasoline and hydraulic.
- Portable power tools present hazards similar to stationary machines performing the same
- Power tools have inherent risk because of its extreme mobility. It can easily come in contact with operator’s body. At the same time it is difficult to guard such equipment completely.
- Dropping or rough handling can cause tools to
- Hazards of exposure to repetitive vibration/motion (repetitive strain injury)
- Also there is inherent hazards of the power source.
The following safety precautions apply for all portable power tools- electrical, pneumatic, hydraulic etc which are covered :
- All portable power tools shall be equipped with spring-loaded switch (dead man switch) which will actuate only when pressed. The switch shall be free from any locking
- User shall always disconnect the tool from power source before maintenance & attaching accessories. Put guard back in place before reuse. Isolate power when not in
- User shall secure the tool in elevated places, so that it will not fall if the cord or hose is
- Avoid excessive force to make cutting tools cut faster. Feed material only as fast as the tool is designed to accept to prevent excessive wear and decreased control.
- User shall not wear loose
- The tools should be suspended to avoid falling on the tool operator, when working overhead position with heavy
- Cords(double rubber insulated type) and hoses should be laid safely to avoid damage and tripping hazards. Avoid laying cords or hoses over sharp
- Braided extension cables shall be used for all power tools to reduce the possibility of damage due to site conditions which could lead to electrocution.
- Avoid accidental starting by ensuring the tool is turned off before it is plugged in. Also do not walk around with a plugged-in tool with the finger touching the switch. Whenever power tool is to be kept unattended even for short period its power supply shall be
- Use clamps, a vice or other devices to hold and support the piece being worked on, when practical to do so. This will allow user to use both hands for better control of the tool and will help prevent injuries if a tool jams or binds in a work piece.
- Follow good housekeeping practices – keep the work area free of clutter and debris that could be tripping or slipping
- Never use power tool with malfunctioning switch or part. Remove it from service and repair or discard if not
- Do not walk on or allow vehicles or other moving equipment to pass over unprotected power cords. Cords should be put in conduits or protected by placing planks on each side of
- Connections shall not be taken over water logged
- Do not surprise or touch anyone who is operating a tool. Startling a tool operator could end up causing an accident or
- Only use accessories recommended by the manufactures. Read the tool manufacturer’s manual to understand the tool’s proper applications, limitations, operation and
- Use the right tool for the job. Ensure it is the right size and has sufficient power to do the job safely. When there is a choice, select a tool of a low
- Select low-vibrating tools as far as possible. Choose tools with vibration-absorbing handles, like those covered with cork, rubber, plastic or plastic bonded to steel, to reduce hand-arm
- Choose hand tools that have the center of gravity within or close to the handle.
- Select tools with rounded and smooth handles that can be gripped easily.
- If they are available, choose hand tools with double handles to permit easier holding and better manipulation of the tool.
- Hold the tool close to the body. Do not
- Keep good balance and proper footing at all times. This will help operators to control the tool better, especially in response to unexpected
- Rest the hands by putting the tool down when not using
- Reduce power to the lowest setting that can complete the job safely. This action reduces tool vibration at the
POWER TOOLS SAFETY
PORTABLE ELECTRICAL TOOLS
- The use of ground wire is mandatory for all electrical tools except the double insulated electrical tools. Ground Fault Circuit Interrupter (GFCI) or Earth leakage Circuit Breaker (ELCB) with earth leakage operating current ≤= 30 mA shall be used. Functionality of ELCB shall be ensured before taking into
- Safe Work Practices on Electrical Safety shall be referred for further details on electrical hazards and
- In wet locations such as in tanks and boiler or on wet floors, low voltage hand tools up to 24 volts are recommended. Additional precautions such as rubber mat and rubber gloves shall be
- Double rubber insulated tools shall be marked with Double Insulatedor symbol of two squares as shown. Such tools shall be stamped by reputed certifying agency such as
- User shall check insulation of tools and cord before and after each use.
- Heavy-duty shock resistant type plugs ( twist lock type)shall be used. Proper extension cord shall be used where
- Eliminate octopus connections: if more than one receptacle plug is needed, use a power bar or power distribution strip that has an integral power cord and a built-in overcurrent
- Manufacturer’s original fittings shall not be altered and improper joints (tape connection) are not
- Power cord of tool should not be used for raising, lowering or carrying the tool.
- Plugging or unplugging of electrical hand tools shall be carried out only after switching off the power socket switches. Power cord shall not be pulled to unplug the tools from the power
- Use of electrical tools such as electrical drill, grinder etc in hazardous classified areas shall be permitted only under Hot Work Permit conditions.
- Keep work areas well lighted when using electric
- Store electric tools in a dry place when not in use.
PORTABLE ELECTRIC DRILL
- Selection of drill bit shall be in accordance with the work piece such as steel, concrete etc.
- If bit is long enough to pass through material, protection against damage to property and injury to personnel must be provided at the far end.
- Telescopic or similar guard must be used, when operating a bench
- Use of electric portable drill shall be allowed only under hot work
POWER TOOLS SAFETY
- Grinding wheel should have the same maximum permissible working speed as the grinder or a higher safe
- Wheel guard must be provided at all times
- Tool rest should be used and adjusted correctly. The rest should not be adjusted when grinder is in
- User should never operate grinders without protecting eyes with safety glasses, goggles and a face shield over it. If the material being worked on will produce a lot of dust or other particles, he shall wear a dust mask or filter
- User shall use visors/face shield which can be fixed to their helmets. Use of independent visor which can be worn by removing hard hats shall not be allowed where there is a possibility of objects falling form heights.
- User shall make sure the grinder has guard housing.
- Before starting a portable grinder, user shall look to see where the sparks might fall. Work area shall be cleaned if
- Allow the wheel to reach full speed before stepping into the grinding position.
- Grind on the face of the wheel unless otherwise designed. Use a vise grip plier or clamp to hold small pieces. Move the work piece slowly across the wheel face.
- Do not apply excessive pressure on tool during sharpening/ grinding tool on the
- Power supply to Portable electric grinding machine shall be turned off when not in
- Allow the wheel to stop naturally when turning it off. Do not attempt to stop by applying external
- Periodically check for soundness of grinding wheels. Replace badly worn, cracked or out-of-round wheels.
- Monitor the shelf life of consumables such as cutting disc & grinding wheels, never use expired
- Debris of grinding wheel shall be segregated as hazardous
POWER TOOLS SAFETY
- Pneumatic tools are powered by compressed air and include chippers, drills, hammers, and sanders. There are several dangers associated with the use of pneumatic tools. First and foremost is the danger of getting hit by one of the tool’s attachments or by some kind of fastener the user is using with the
- Pneumatic tools must be checked to see that the tools are fastened securely to the air hose to prevent them from becoming disconnected. A short wire or positive locking device attaching the air hose to the tool must also be used and will serve as an added
- If an air hose is more than 1/2-inch (12.7 millimeters) in diameter, a safety excess flow valve must be installed at the source of the air supply to reduce pressure in case of hose
- Pneumatic tools that shoot nails, rivets, staples, or similar fasteners and operate at pressures more than 100 pounds per square inch(689 kPa), must be equipped with a special device to keep fasteners from being ejected, unless the muzzle is pressed against the work surface.
- Airless spray guns that atomize paints and fluids at pressures of1,000 pounds or more per square inch (6,890 kPa) must be equipped with automatic or visible manual safety devices that will prevent pulling the trigger until the safety device is manually
- In general, the same precautions should be taken with an air hose that are recommended for electric cords, because the hose is subject to the same kind of damage or accidental striking, and because it also presents tripping
- Air hoses shall be coupled, locked and secured from undesired movement before opening air supply valve. A safety clip or retainer must be installed to prevent attachments such as chisels on a chipping hammer from being ejected during tool
- Eye protection is required, and head and face protection shall be worn by employees working with pneumatic tools. A face shield also shall be used in addition to safety
- Screens must also be set up to protect nearby workers from being struck by flying fragments around chippers, riveting guns, staplers, or air
- Noise is another hazard associated with pneumatic tools. Working with noisy tools such as jackhammers requires proper, effective use of appropriate hearing protection. Refer HSE Document “PPE Program” for selection of appropriate
- Good quality air hoses with proper pressure rating and standard coupling with locking arrangement shall be used. Supply air pressure shall not exceed the design pressure of the tool and accessories. Follow procedure on utility station hose care and
- Air hoses shall be inspected for soundness before use. It shall be periodically tested as per manufacturer’s
- Air hose should not be used for cleaning dust on machines or
- Before disconnecting air hose, supply valve shall be
- Make sure that hose connections fit properly and are equipped with a mechanical means of securing the connection (e.g., chain, wire, or positive locking device).
- While working in inert atmosphere nitrogen driven pneumatic tools shall be used.
POWER TOOLS SAFETY
- Always wear proper protective equipment. Safety glasses or shield, hearing protection(shall wear double ear protection – both ear plug and ear muff), and breathing protection shall be
- Check all bits to see that they are sharp. If not, sharpen according to the manufacturer’s recommendations.
- Always disconnect the air supply before inserting or removing
- Be sure all tools are properly locked into the unit before
- Allow the tool to do the work by using a grip light enough to maintain control.
- Maintain a firm grip at all times, but do not squeeze the handles with constant, excessive pressures, take frequent
- If stopping work for a short period of time or for the day, stop the compressor.
- Use of heavy jackhammers can cause fatigue and strains. Heavy rubber grips reduce these effects by providing a secure
- Proper hose NPT fittings to be used for pneumatic jack
POWER TOOLS SAFETY
- Use only suitable fluid that will retain its characteristics at the highest temperatures to which it will be
- Do not exceed the manufacturer’s recommended operating pressure for any
- Hose assemblies must be inspected prior to each use. Worn out fittings, attachment devices, hose and accessory items must be
- All hose assemblies be tested in accordance with the hose manufacturer’s specifications. The application determines the regularity of the re-testing schedule.
- Retaining devices (safety devices) such as clips, cables or chains must be used. Clamps must be checked regularly to the specified
- Under no circumstance should any coupling be disconnected while under pressure unless the coupling is specifically designed to do
- Disconnecting couplings under pressure could result in serious injury or death, and destruction to property and equipment. Hence ensure that the pressure is fully released while disconnecting couplings under pressure.
- Any leaks on a hydraulic circuit shall be rectified immediately as per manufacturer’s recommendation.
- Oil & lubricants shall be stored as per the manufacturer’s instructions. Monitor the shelf life of oil & lubricants, never use expired items.
POWER TOOLS SAFETY
- All jacks – lever and ratchet jacks, screw jacks, and hydraulic jacks – must have a device that stops them from jacking up too high.
- Manufacturer’s load limit must be permanently marked in a prominent place on the jack and should not be exceeded.
- A jack should never be used to support a lifted load. Once the load has been lifted, it must immediately be blocked
- Use wooden blocking under the base if necessary to make the jack
level and secure. If the lift surface is metal, place a 1-inch-thick hardwood block or equivalent between it and the metal jack head to reduce the danger of slippage.
- To set up a jack, make certain of the following:
- the base rests on a firm level surface,
- the jack is correctly centered,
- the jack head bears against a level surface, and
- the lift force is applied
- Proper maintenance of jacks is essential for safety.
- All jacks must be inspected before each use and lubricated
- If a jack is subjected to an abnormal load or shock, it should be thoroughly examined to make sure it has not been
POWER TOOLS SAFETY