Health and safety in engineering workshop

HEALTH AND SAFETY IN ENGINEERING WORKSHOP

Oleh : Bayu Nurwinanto

Working In and Moving Around The Workshop

About two thirds of all accidents is small engineering workshop happen during the movement of vehicles, people and goods. A safe, well-lit, clean workplace can help prevent many of these.

*Particulary on the the flat roofs of offices provided in small industrial units, which are often used for stroge; proper stairs should be provided for frequent access to these areas.

Maintenance

Maintaining the workshop and the equipment in it may pose different hazards from those encountered in the normal run of production work. Contractors as well as your own employees may be at increased risk, particularly during the repair and cleaning of plant containing toxic, flammable or hazardous materials, machinery and during work at heights or in confined spaces.

Lifting Equipment

Although lifting, Supporting dan handling equipment can lighten the load of manual handling when properly used, many accidents happen when loads are dropped from lifting equipment, either because of poor slinging, or equipment failure or overloading.

The Law On Lifting Equipment Outlined

The same regulations now apply to all lifting equipment, which includes any equipment, which includes any equipment used at work for lifting or lowering load, and lifting accessories such as chains, slings, eyebolts etc.

You should ensure that :

• Lifting equipment is sufficiently strong, stable and suitable for the proposed use, and marked to indicate its safe working load.
• Lifting eguipment is positioned or installed to minimise the risk of injury, eg from the eguipment or the load falling or striking people;
• Every part of a load (including, for example, pallets and stillage) and anything attached to the load and used in lifting (including for example the lifting points on skips) is of adequate strength;
• Lifting operation are planned, supervised and carried out in a safe manner by people who are competent;
• Lifting equipment (including accessories) is thoroughly examined for any defect it is put into service for the first time ( unless it is new and is covered by an EC declaration of conformity which is less than 12 month old ). Where the safety of lifting equipment depends on installation conditions, it must be thoroughly examined after installation and before being put into use for the first time. Periodic thorough examinations are also required at six- monthly intervals for accessories and equipment used for lifting people, and at least annually for all other equipment; or at intervals laid down in an examination scheme drawn up by a competent person.

Moving Good Safely By Hand

The unsafe movement of goods by hand, either by lifting or handling causes more accidents and ill health in small engineering workshops than any other single activity, especially to those most at risk, including the younger more inexperienced employees, the older and/or less physically fit, and those who may make an existing injury worse.

Back injuries are very common as are hand, arm, shoulder and neck injuries, particularly from unsafe, highly repetitive work. Cuts and abrasions from sharp edges are also very numerous.

Manual Handling Operations Regulations Outlined :

Employers must :

• Avoid the need for hazardous manual lifting and handling if reasonably practicable.
• Assess the risk of injury from any hazardous manual lifting and handling which cannot be avoided; and
• Reduce the risk of injury accordingly.
• Follow safe system of work laid down by their employers.
• Use mechanical aids provided by their employers properly.
• Remember to use the training provided on lifting.

Sharp Edges

These cause as many as a third of all accidents in some engineering workshops, resulting in cuts, abrasions, infected wounds, dermatitis, amputations and occasionally fractures.

Those working with sheet metal, either flat or coiled, heavy sharp items, such as tools and cutters, and scrap metal and swarf are most at risk.

Consider how to avoid handling sharp edges, and if this is not reasonably practicable, reduce exposure to them.

Reducing The Risks

• Ask your supplier to remove or protect sharp edges, eg by machining out sharp edges or
• fitting plastic covers or padding.
• Remove sharp edges or protect them before handling.
• Avoid handling by using, for example trays, jigs, holders or baskets.
• Minimise handling by automating processes by using, for example conveyors, feed anddischarge chutes.
• Strore articles correctly so that they are retrieved easily.
• Use personal protective equipment such as gloves, gauntlets and aprons, but only where these do not add to other risks from machinery, such as entanglement.

How To Lift Safely

Here are some important points, using a basic lifting operation as an example. Plan the lift. Where is the load to be placed? Use appropriate handling aids if possible. Do you need help with the load? Remove obstructions such as discarded wrapping materials. For a long lift, such as floor-to-shoulder height, consider resting the load mid-way on a table or bench in order to change grip.

Position the feet

Feet apart, giving a balanced and stable base for lifting (tight skirts and unsuitable footwear make this difficult). Leading leg as far forward as is comfortable.

Adopt a good posture

When lifting from a low level, bend the knees. But do not kneel or overflex the knees. Keep the back straight (tucking in the chin helps).

Lean forward a little over the load if necessary to get a good grip. Keep the shoulders level and facing in the same direction as the hips.

Try to keep the arms within the boundary formed by the legs. The best position and type of grip depends on the circumstances and individual preference; but it must be secure. A hook grip is less tiring than keeping the fingers straight. If you need to vary the grip as the lift progresses, do it as smoothly as possible.

Keep close to the load

Keep the load close to the trunk for as long as possible. Keep the heaviest side of the load next to the trunk. If a close approach to the load is not possible, slide it towards you before trying to lift.

Lift smoothly, keeping control of the load. Don't twist the trunk when turning to the side. If precise positioning of the load is necessary, put it down first, then slide it into the desired position.

Training For Lifting And Handling

This should cover :

• How to recognise harmful manual handling.
• Appropriate systems of work.
• Use of mechanical aids.
• Good handling technique.

Controlling Hazardous Substances

Exposure to hazardous substances most frequently occurs when :

• Machining.
• Welding.
• Painting.
• Cleaning and degreasing.

The control of dust, fume, spray and vapour-and the prevention of skin contact by adequate personal protection -will minimise risks of adverse health effects, but pay particular attention to precautions when machining, welding, polishing or grinding :

• Nickel-copper and nickel-chrome alloys (found in coins, magnets, chemical and food process equipment and in the aerospace industry).
• Stainless steel and nickel alloys; stainless steel and chromium alloys.
• lead and lead alloys.
• Copper alloys containing beryllium (commonly found in the electrical industry and in high definition tools and dies -used, for example, in plastic injection moulding machines).
• Cadmium-plated articles.

The Health And Safety At Work Etc Act 1974, Section 6 In Relation To The Supply Of Substances For Use At Work Outlined:

Suppliers must :

• Ensure so far as is reasonably practicable that the substance will be safe and without risks to health.
• Provide adequate information about any risks to health or safety to which the inherent properties of the substance may give rise.

Labels and safety data sheets supplied with hazardous chemicals contain important information about hazards to help you use them safely.

The most common health effects from hazardous substances are :

• Skin diseases such as dermatitis from metalworking fluids and oils.
• Lung problems, such as asthma, from isocyanate paints and glues.
• Poisonings, such as lead poisoning, and
• very rarely cancer, such as skin cancer from certain mineral oils.

A hazard may be defined as something that can cause harm -such as the chemicals in a tin of paint -while a risk may be seen as the chance of harm actually being done -which can vary with how the paint is actually used; spraying in an uncontrolled environment without personal protection could pose high levels of risk.

Local Exhaust Ventilation (Lev)

Selection and use:

LEV is a frequently used way of controlling exposure to hazardous substances by drawing them away from the breathing zones of workers into a hood and ductwork connected to an extract fan.

In many circumstances LEV may be cheaper and more effective than dilution ventilation. (Dilution ventilation works by introducing fresh air into the workplace to lower the general level of the hazardous substances in the air).

Heat losses from LEV may be minimised by heat recovery systems or recirculation of filtered air, but the latter only after specialist advice to prevent the recirculation of hazardous materials in harmful quantities.

The Law On Maintenance, Examination And Testing Of Lev Outlined :

In most small engineering workshops, employers must ensure that thorough examinations and tests are carried out :

• Every 14 months for most processes.
• Every six months where metal articles are abraded or polished for more than 12 hours a week.

Employers must also keep appropriate records for at least five years.

Someone with sufficient training, knowledge, skills and experience is required for the maintenance, examination and testing of LEV, and insurance companies frequently have the competence required.

To Make The Most Of LEV:

• Get an expert to design and install the most appropriate system, with the right hoods/enclosures, ductwork, air velocities and cleaning and filtration systems.
• Make sure the fan draws air away from the operator.
• Make sure partial enclosures are large enough to contain the work and that sprayers do not stand between the workpiece and point of extraction; consider a turntable for heavy items.
• Check and maintain the system regularly particularly flexible ductwork.
• Provide sufficient lighting (suitably protected) within the enclosure to encourage work to be done within the extracted area.

Common causes of LEV failure, which you can check easily and frequently yourself to keep it working properly include :

• Physical damage to and poor positioning of hood and booths.
• Damaged and/or blocked ductwork.
• Blocked, damaged, unsuitable or incorrectly intalled filters.
• Too high/low water levels in wet collectors.
• Wear or corrosion of fan blades leading to build up of contaminant on blades.
• Slipping drive belts to fan.
• Poor lubrication of fan bearings.

LEV used to help draw welding fume from the breathing zone of a welder and 
Spraying in the direction of exhaust ventilation air movement; a turntable can
help a sprayer avoid standing between the item being sprayed and the point of air
 extraction from the booth

Electricity

How Most Accidents Happen

Most accidents arise from contact with live conductors or equipment made live by faulty wiring and connections. Equipment using 240v AC may be as dangerous as that using 415v AC, depending on circumstances. Each year, the use of electricity causes fatal and other injuries (eg burns) from electric shock and fire.

The Law On "Live"Electrical Work Outlined :

No electrical work should be carried out `live' where there is a possibility of contact with a potentially dangerous live conductor unless :

• It is unreasonable in all the circumstances for the equipment to be dead; and
• it is reasonable in all the circumstances for the work to be carried out on or near it while it is live; and
• Suitable precautions (including, where necessary, suitable protective equipment) have been taken to prevent injury, such as proper work planning and the use of adequately trained and supervised staff.

PRECAUTIONS necessary to prevent accidents require everyone in the workshop (including the self-employed) to use equipment safely and co-operate with the employer where necessary.

Employers in particular need to:

Develop a suitable system of maintenance for both fixed installations and portable equipment -advice from a competent person may be required.

Ensure that electrical contractors are competent for the work they are expected to do; for example, are they registered with such organisations as the National Inspection Council for Electrical Installation Contracting or equivalent?

select equipment which is suitable for the job (using reduced low-voltage equipment lowers the risk of serious injury).

Check that wiring and equipment is sound and properly installed, especially so that protection equipment such as fuse and switchgear will operate adequately in the case of faults. Universally accepted standards are described in BS 7671 Requirements for electrical installations.

Ensure any electricians working for you are competent. Levels of qualification established by the Electrical Joint Industries Board may be of help here, but check that qualifications are relevant; a fully qualified TV technician may not be competent to re-wire a building.

Pressurised Plant And Systems

The Law On Pressurised Plant and Systems Ountlined :

• All plant and systems must be designed, constructed and installed to prevent danger.
• Systems must be properly maintained.
• Modifications or repairs must not cause danger.
• There must be a written scheme for examination of certain pressure vessels, such as air receivers, steam boilers, fittings and pipework, drawn up by a competent person.
• Examinations as set out in the written scheme must be carried out by a competent person.
• Records must be kept in most cases.

Pressure Testing

• Accidents, some fatal, occur during pressure testing when the energy contained in the vessel under test is released with explosive force.
• Wherever practicable, avoid using compressed air, steam or gas (which contains more than 200 times the energy of water of the same volume).
• Use hydraulic (liquid) pressure with suitable precautions and always, if possible, before leak testing (using air, steam or inert gas) components not intended as pressure vessels, eg vehicle fuel tanks, radiators, small castings, storage tanks and oil drums.

Injection Injuries

• Injuries, occasionally fatal, may be caused by accidental or deliberate injection of material and/or compressed air either through the skin or into a body orifice.
• Ordinary working clothes do not significantly resist the penetration of compressed air into the body.
• High-pressure fluid guns may inject material at 3-7000psi and cause serious injuries. Care should be taken to avoid accidental injections.
• Horseplay' should be strictly forbidden.
• Because the degree of injury may not always be immediately apparent, medical advice should always be sought after compressed air penetration occurs or is suspected.

Noise

Too much loud noise damages hearing by causing :

• Deafness, or
• Permanent tinnitus (ringing in the ear).

If you cannot hear clearly what someone is saying (in a normal voice) 2 m away, the noise level is likely to be 85dB(A) or higher:

Typical Minimum Noise Levels Next To Operations Where No Steps Have Been Taken To Reduce Noise	dB (A)
Air Exhauting from pneumatic equipment.	85-95
Grinding on pedestal grinder	90-95
Discharging metal objects into metal tins/chutes	85-95
General noise level in fabrication shop	85-95
Using vibratory bowl feeders	90-100
Hammering steel	95-100
Guillotining	95-100
Multi-Spindle automatic turning	95-105
Circular sawing - metal	95-105
Pressing -Blanking -Punch Pressing	95-110 110-120
Riveting	100-110

Actual noise levels can be higher than those shown above.

Measuring Noise

Exposure to noise is measured in decibels -usually written as dB(A). The noise level (loudness) is measured as a scale from a silent zero dB(A) to 140dB(A) for the noisiest situations. For most jobs risk depends not only on noise levels but how long people are exposed to them. The total amount of noise exposure over the whole working day is called the daily personal noise exposure (usually shortened to LEP,d).

Many engineering workshops may need to have their noise levels measured. This should be

done by people who understand and can apply HSE's guidance on how to measure noise.

Welding And Flamecutting

Common causes of ILL Health are :

• Inhalation of harmful welding fume.
• Unsafe handling of workpieces and welding equipment, particularly gas cylinders.
• Noise, particularly from plasma arc cutting, gouging operations and weld preparation.
• Burn from ultra violet radiation, including ‘arc eye'.
• Vibration during grinding for weld preparation.
• Discomfort from heat and uncomfortable postures.

Key Safety Measures

for arc welding :

• Extraction equipment.
• Provide appropriate protective clothing and ensure it is worn, eg overalls, protective apron, gloves, safety boots, respiratory protection (if necessary).
• Use welding screens and eye protection (to BS 679) to prevent arc eye.
• Local isolation switch.
• Welding set transformer.
• Workpiece earth when required.
• Insulated electrode holder.
• Insulated box for electrode holder.
• Proper cable connections.
• Suitable fire extinguisher easily accessible.
• Welding leads should be insulated, robustly constructed and big enough carry the current safely.
• Residual current devices may enhance safety.
• Work in confined spaces and on large structures supported on manipulating devices needs special precautions.

Common Causes Of Accidents Are :

As a result of :

• Falling gas cylinders.
• Particles entering unprotected eyes during chipping after welding.
• Electric shocks from arc welding equipment.
• Fires started by flames, sparks and hot material from welding and cutting processes.
• Fingers being crushed between the electrodes of fixed resistance welding machines.

Control Of Fume And Gases At Welding, Flamecutting and Similar Processes Such As Brazing And Soldering

Fume from welding, flamecutting, brazing and soldering varies greatly in composition and Concentration. Different jobs lead to different levels of exposure to different susbtances. Fume from welding and flame cutting may cause.

• Dryness of the throat. Tickling, coughing tightness of the chest and difficulty in breathing.
• An acute flu-like illness (metal fume fever).
• Long-term changes in the lung.

Welding or cutting processes releasing the greatest quantities of harmful fume include :

• Work on metallic coating such as cadmium or zinc plating and chromium, manganese, cobalt and/or nickel hard surface.
• Work on pained surfaces which contain lead, zinc, chromium or cadmium pigments.
• Mechanised flame cutting.
• Flame gouging.
• Frequent and regular manual metal arc welding.
• Flux cored electrode welding.
• Higher current metal inert gas shielded welding particularly on sainless steel and aluminium, copper, nickel and their alloys.
• Oxygen arc welding and gouging.
• Using cadmium-containing solder.

Minimise Risks :

• Avoiding welding and flamecutting, using other bonding and cutting techniques where reasonably practicable.
• Using safer filler materials, such as cadmium free silver solder.
• Controlling exhaust fume by providing local exhaust ventilation unless a detailed and thorough risk assessment shows that harmful fume is not being generated or that it may be controlled by general ventilation.
• Providing respiratory protective equpment, but only if control measures are unable to reduce fumes to safe levels.
• Ensuring workshops have enough low-level inlets and high-level outets for air changes.
• Not welding near (10 m for most welding; 20 m for aluminium) cleaning processes using chlorinated solvents; the heat and arc from welding may break down the solvents info more harful subtances.

RADIOGRAPHY

X-rays, gamma rays and other forms of radiation used for non-destructive testing (NDT) may injure by causing burns, dermatitis, cancer, cell damage, blood changes or cataracts.

The Ionising Radiation Regulations 1999 Outlined :

If radiography is carried out in your workshop you (or, if a contractor is doing the work, they) must :

• Notify HSE before starting work.
• Consult a suitable radiation protection adviser.
• Carry out a prior risk assessment.
• Arrange for medical examinations/reviews and routine dose assessments of employees whom you designate as "classified persons".
• Appoint one or more of your employees to supervise radiation work.
• Provide local rules and training.
• Make arrangements to deal with stuck radioactive sources, x-ray exposures failing to terminate, etc and rehearse them. Get authorisation for the use, storage and safe disposal of radioactive substances from the Environment Agency/SEPA, as appropriate.

Other non-destructive testing techniques, such as magnetic particle and dye penetrant techniques may involve the spraying of harmful solvents. Exposure to harmful levels of such solvents needs to be assessed in line with COSHH and prevented or controlled.

To Minimise Risks :

• Always carry out routine radiography of readily moveable articles inside a permanent shielded enclosure, sufficient to limit dose rates outside the enclosure to less than 7.5 microsieverts an hour.
• Make sure there are no people near open-topped enclosures (in offices, or overhead crane cabs, for example) who may be affected.
• If you change your generator or source you may have to upgrade the enclosure.
• Have to hand an emergency plan and the equipment necessary to put the plan into effect (for radioactive sources to include bags of lead shot, a shielded pot and long-handled tools) and rehearse the plan.
• Wear your dosemeter when required and make sure it is not damaged or exposed to radiation when not being worn.
• Use a maintained and tested radiation dose rate meter to check radiation levels around the controlled area and always use the monitor when approaching the source container to check the that the sealed source has fully retracted or x-ray generator is no longer producing x-rays.
• Maintain radiography controls, for example windouts and guide tubes for sealed source equipment, and warning devices.

If You Can't Do The Work In A Shielded Enclosure, You Must :

• Notify HSE at least seven days in advance of each occasion on which you propose to work.
• Plan the work to ensure radiation exposures are suitably restricted by use of collimation and localised shielding, barriers, warning signals, lighting and other means to demarcate the controlled area.