Section 7: Precautions with Work Equipment
Great care should be taken when using any machinery to avoid both personal injury and damage to equipment. School codes of workshop practice, establishing who may use any particular equipment, the times of such use and the conditions governing such use, must be strictly observed.
Only trained and authorised persons should be allowed to use hazardous equipment and adequate arrangements should be made to prevent their use by unauthorised persons.
The Provision and Use of Work Equipment Regulations 1998 apply to work equipment, the definition of work equipment being any machinery appliance, apparatus or tool, or any assembly of components which in order to achieve a common end are arranged and controlled so that they function as a whole. This definition is very wide and examples would include power press, guillotine, air compressor, lifting sling, microbiological safety cabinet, portable drill and overhead projector.
The regulations cover two aspects of safety in relation to work equipment:
- Management issues - selection and suitability, maintenance, information, instruction and training and compliance with Product Safety Regulations.
- Physical characteristics - machinery guarding, other specified hazards, extremes of temperature, controls, isolation, stability, lighting, markings and warnings.
Suppliers of work equipment have a duty to design work equipment in line with these regulations and Schools should be aware of the requirements when introducing new work equipment.
The Supply of Machinery (Safety) Regulations 1992 are one example of product safety regulations. These regulations give essential health and safety requirements which equipment should be designed in accordance with, prior to supply in EC countries. The CE mark should indicate that relevant product safety regulations have been complied with.
For further details, please refer to Safety Office Circular, Safe Use of Work Equipment, P5/95C. The sections below deal with specific issues and certain types of equipment.
Certain types of equipment can contain a radioactive source even though the equipment might not be considered as being used for radioactive purposes. An example is the use of a small source as part of a monitor or detector (e.g. electron capture detectors used with some gas chromatographs and some types of static eliminators). The information provided by the manufacturer or supplier should indicate if a radioactive source is present. The Safety Office must be notified in advance of the equipment coming onto site as these sources are strictly regulated.
Loose clothing must not be worn near moving machinery. Particular attention should be paid to ties and other forms of neckwear. Suitable footwear must be worn in workshops and laboratories. Long hair must be protected from contact with machinery by wearing suitable headgear. Goggles must be worn when using grinding wheels or any other process where there are flying particles. The use of dust masks is recommended where there is prolonged exposure to dust or particles. Rings should not be worn when using machinery.
Hazardous machinery must always be guarded. The British Standards Institute has published a document, PD5304:2000, “Safe Use of Machinery” which gives practical guidance on complying with the relevant BSEN Standards (which are also listed). This document can be accessed through the Safety Office website.
Do not use machinery without the appropriate guards and be sure that guards are replaced after a machine has been re- set. Guard interlocking devices must never be defeated. Report any defects in guards or interlocks immediately.
Suitable guards should be provided for destructive testing machines to prevent injury from any flying particles.
It is the aim of the University to minimise the risk of noise induced hearing damage to all who may be affected by keeping exposure to noise as low as is reasonably practicable and where the Upper Action Value is likely to be exceeded, control measures will be put in place to reduce it. Heads of Schools must ensure that appropriate measures are taken to deal with noise from machinery.
The Noise at Work Regulations require that assessment of noise levels must be made wherever there is a noisy environment. In any cases of excessive
noise, steps must be taken to reduce this at source. If this is not practicable then ear protection must be made available to employees, who must wear it in any prescribed areas of high noise level.
The lower exposure level (first action level) is 80dB(A) as an 8-hour time-weighted average (8-hour TWA). This is the level at which hearing protection must be made available.
The upper exposure level (second action level) is 85dB(A) (8-hour TWA). This is the level above which engineering controls should be used as far as is reasonably practicable to reduce the noise exposure, for example by noise enclosure of equipment, silencers, sound refuges etc. Where noise levels remain above this the area will become a compulsory hearing protection area.
There is also an Exposure Limit Value of 87dB(A) (8-hour TWA). This is the level of noise above which a person may not be exposed having taken into account the noise controls to be used and the pattern of exposure.
The peak sound pressure level is 137dB(C) - i.e. from instantaneous or percussive operations.
Audiometry is required for those exposed to noise above 85dB(A) and is carried out by Occupational Health. This should be done initially and every 3 years although in some circumstances Occupational Health might consider that shorter intervals of 1 or 2 years are appropriate. Individuals can also request a check in between if they have any concerns.
Further more detailed guidance is published on the Safety Office website.
Only authorised persons who have received an approved course of instruction are allowed to change or dress abrasive wheels. The maximum spindle speed should be marked on the equipment.
The grinding of aluminium and magnesium requires special care and the appropriate literature should be consulted.
Electric welding is a powerful source of light with a high ultra violet light content which is very dangerous to the eyes (see section on electromagnetic radiations). Any areas where welding is taking place must be suitably screened and ventilated.
Manual electric arc welding involves the operator working in close proximity to the live electrode and the workpiece with the consequent danger of receiving an electric shock. Although relatively low voltages are involved whilst welding, higher open circuit no-load voltages are required to strike the arc. These can be up to 80V ac or 100V dc and can be dangerous in confined conducting locations or wet surroundings. Earthing of the workpiece and of any metalwork in contact with it is important. The welding return lead should be placed as close as possible to the point of welding. The welding leads should be fully insulated. In the case of the return lead poor positioning or damaged insulation can result in stray currents which could damage safety critical parts of other equipment.
Hot Work is defined as work involving the application or generation of heat such as cutting, welding, brazing, soldering and the use of blowlamps. Hot work involving the application of heat, either directly to, or adjacent to plant, tanks, vessels and pipes that have contained or do contain explosive, flammable or toxic substances can create the following hazards:
- Explosion as a result of flammable vapours under pressure being ignited within a confined space.
- Fire from sparks and heat generated in areas containing combustible and flammable materials
- Eye injury including ultra-violet damage, burns, heat exhaustion
- Asphyxiation by gases or vapours or poisoning by toxic fumes
For routine hotwork, such as that carried out in designated facilities, a standard operating procedure must be drawn up which can be followed each time the hotwork is carried out.
For non-routine hotwork, a risk assessment must be carried out by a competent person and a Permit to Work issued for each job taking into account the specific hazards involved. This applies to hotwork carried out by contractors as well as University staff.
Further guidance is available in Safety Office Circular P7/00A.
The main hazards from compressed gases are
- Explosion of the cylinder due to mechanical damage, weakness or over-pressurisation
- Exposure to released gas or fluid, which may have harmful properties [asphyxiant, toxic, corrosive]. Oxygen is particularly dangerous as it can promote fires and explosion and sustains combustion.
- Fire due to escape of flammable gas/fluid.
- Over-pressurisation in the event of fire
- Impact from falling cylinders
- Manual handling injuries
The following standard precautions should be observed.
- No person should use a gas cylinder or change the cylinder regulator unless they have received appropriate training and are authorised to do so by their supervisor or line manager.
- Ensure the regulator and pipework is appropriate for the type of gas and pressure regime.
- Wear a suitable face visor or safety glasses [to protect against impact] when changing/fitting regulators.
- Do not use grease or PTFE tape on threads - this can present an explosion risk and indicates unsatisfactory seal being made which could leak.
- Check for leaks using leak detection fluid - proprietary sprays are recommended. [Tepol/water can be used as vegetable based but soapy water must not be used as it is oil-based].
- Use only brass spanners (these do not create sparks) when fitting regulators to cylinders of highly flammable gas.
- Ensure the cylinder is secured in a trolley or securely chained/strapped to the wall or bench.
- Transport cylinders in suitable trolleys with dust cowls in place.
- Wear suitable safety shoes when transporting cylinders.
- Store in a safe place outside or in a room that has adequate ventilation.
- Do not store flammable gases near any source of ignition.
Gas cylinders should be handled gently and used only with the correct fittings. In particular the materials from which any components of the system are made should be compatible with the gas being used. Detailed information on this is contained in British Compressed Gases Association publications (CP4 and CP5 are particularly relevant and can be accessed via the safety Office web-site). They should always be secured to prevent them being knocked over accidentally. Cylinder valves must not be lubricated.
Cylinders of compressed gases can be a hazard if fire breaks out. Wherever practicable all cylinders containing gas should be kept outside a building in a well-ventilated area.
Oxygen is particularly dangerous since it is more likely to promote fires or explosions than is air. Compressed air should be used with caution and never in the context of practical jokes.
Acetylene used at > 9p.s.i. is subject to specific regulation and special notification to the appropriate agency is required. Contact Safety Office for details.
Inspection & maintenance.
Schools/departments where compressed gases are used/stored should ensure that regulators and their associated pipe-work are inspected visually and tested for correct function and leaks by a competent trained person at least annually.
Regulators used with flammable/toxic/corrosive gases should be refurbished or replaced every five years. Those used with inert gases should be kept on annual review based on inspection.
Further practical guidance is contained in the BOC publication ‘Safe Under Pressure [also available on video] and in HSE Guidance note INDG 308 [May 2000] ‘The safe use of gas cylinders’.
Paint spraying must only be carried out in a suitably ventilated area or booth complying with the appropriate regulations. Particular care must be taken when using isocyanate containing (“2-pack”) paints since this material is a potent respiratory sensitiser. Additional precautions include total protective clothing, airline-fed breathing apparatus and health surveillance by the Occupational Health Unit (see http://www.nottingham.ac.uk/safety/respiratory.htm)
7.9 Woodworking Machinery
Woodworking machines are particularly dangerous and difficult to guard and it is essential that only adequately trained persons should operate them. Access by other persons must be prevented. The Woodworking Machines Regulations 1974 have been revoked and superseded by the Provision and Use of Work Equipment Regulations 1998. In addition there is HSE guidance and an approved code of practice specifically concerning the safety of Woodworking Machinery.
Large quantities of energy are stored in the rotor of a centrifuge when in operation and it is necessary for users to have adequate instruction in the correct method of operation of these machines.
Centrifuges should conform to British Standard 4402: 1982. Guidance on the requirements of this standard is contained in the attachment to Safety Office Circular 4/89F.
Work should not be done from ladders if it is reasonably practicable to use other forms of access equipment - see Section 6.3 for guidance on work at height.
Ladders and other forms of access equipment should be inspected regularly, including before and after use, and if any defect is found immediate action should be taken. Wooden ladders and steps must not be painted. They should be checked for rot, decay or mechanical damage such as warped stiles, excessive cracks, splintering and wear and tear at the head and foot of the stiles. Rungs should be checked for looseness, excessive wear, or decay where the rung enters the stile. Metal ladders should be checked for twisting, distortion, oxidation, corrosion and excessive wear, especially on the treads.
In use a ladder must always stand level and firm footing and be placed at an angle of 75 degrees (1 foot horizontal for each 4 feet vertical).
For ladders less than 10 feet long it is sufficient to ensure that the ladder is securely placed so as to prevent it from slipping of falling. Longer ladders should be securely fixed at the upper end or if this is not practicable, at or near the lower end. If neither of these is practicable then a person must be stationed at the foot of the ladder when in use to prevent it slipping, but this concession can only be applied when the ladder is less than 20 feet long.
Arrangements should always be made to support the ladder to prevent undue swaying or sagging. When in use over- reaching and the carrying of loads should be avoided.
Each School/Department owning lifting equipment will have appointed a Responsible Person to co-ordinate maintenance and examination of such equipment. All new items of lifting equipment must be notified at the time of installation or purchase to the Responsible Person who will arrange for them to be insured and regularly inspected in line with the Lifting Operations and Lifting Equipment Regulations 1998. The procedure for this can be found on the Procurement Website (follow the links to Insurance; Engineering and Statutory Inspections; Standard Inspections for Pressure Vessels and Lifting Equipment).
Equipment such as lifts, cranes, chairs, ropes and slings must not be loaded beyond the safe working loads specified for each one. Safe loads must be clearly marked on each piece of equipment and the appliances should be tested periodically, as advised by the insurance inspector.
Forklifts must be operated by authorised persons only. The standard to which operators should be trained is specified in the Approved Code of Practice “Rider Operated Lift Trucks - Operator Training”.
The Pressure Safety Systems Regulations 2000 require that all pressure vessels and associated pipework must be assessed initially to determine the appropriate regime of regular inspection and testing ("written scheme of examination"). Thereafter arrangements must be made for this inspection and testing to be undertaken at the correct intervals.
Therefore the details of all systems, including for example autoclaves and air receivers, must be notified at the time of installation or purchase to the Department or School's Responsible Person, who will arrange for them to be assessed, insured and regularly inspected. The procedure for this can be found on the Procurement Website (follow the links to Insurance; Engineering and Statutory Inspections; Standard Inspections for Pressure Vessels and Lifting Equipment).
The safe working limits of the system must be clearly marked on it. As a minimum this should include the maximum pressure for safe working. Larger, complex systems may also require marking with temperature, time, volume, flow rate, heat input or coolant flow limits as appropriate. The operating instructions should contain all the information needed for safe operation of the system including start-up, shutdown, standby and emergency situations.
In addition to any thorough examinations in accordance with the written scheme, the system should be subject to routine maintenance and inspection checks. These checks should include looking for signs of corrosion, leakage and external damage. Particular attention should be paid to the seals at doors and lids. Systems should be regularly cleaned out or drained of condensate, to ensure the removal of corrosive residues.
Staff operating autoclaves must receive adequate instruction and supervision. Manufacturer’s operating instructions must be observed at all times. Any seals or pressure relief valves should be examined carefully at frequent intervals for signs of wear, usually cracking or hardening. Seals and valves may also require regular replacement irrespective of condition—follow manufacturer’s recommendations.
Always wear a face visor and heat resistant gloves when removing material from the autoclave and never attempt to do so until the temperature of the contents is below 80 C otherwise an explosion may occur.
University vehicles must be driven only by appropriately trained and authorised persons. This includes forklift trucks and other battery operated vehicles. In particular, drivers of rider-operated forklift trucks must have
passed an accredited course of instruction and be formally authorised for a specified period of time.
Drivers must be aware of any special areas into which vehicles must not be taken, e.g. areas in which highly flammable liquids are used or stored. Fuel for vehicles or stationary engines must be kept in the appropriate licensed storage.
If a vehicle becomes faulty, there must be a system for this to be reported immediately. If the fault is potentially dangerous, e.g. in the braking system, arrangements must be made for all potential users to be made aware of this and for the vehicle to be rendered physically incapable of use until satisfactory repairs have been carried out.
Please see section 6.33 for Minibus Driving information.
Prolonged use of high-vibration hand-held or hand-guided tools is associated with a risk of developing Hand-Arm Vibration Syndrome (HAVS). This condition may result in effects to the hands and arms, including impaired blood circulation and damage to the nerves and muscles. It is felt as a tingling or numbness in the fingers or where finger blanching occurs. There are other names for the condition: 'vibration white finger', 'dead finger' and Secondary Raynaud's Syndrome. There are however other medical conditions that may cause similar effects.
The affects are cumulative and as time passes the attacks may involve considerable pain and loss of manual dexterity, resulting in clumsiness and reduced grip strength.
Although the risk depends on the magnitude of the vibration and length of exposure, the grip, push and other forces used to guide and apply vibrating tools or workpieces, temperature, smoking and individual susceptibility can also influence the condition.
The following is an indicative list of the types of equipment found in the University that may present a vibration hazard:
- Grounds work, e.g. chainsaws, strimmers, mowers, blowers, hedgetrimmers, etc.
- Workshop equipment, e.g. grinding tools, rotary burring tools, powered hammers, concrete breakers, sanders and drills.
- Grinders and other rotary tools
- Timber and wood machining tools
- Percussive metal-working tools
- Percussive tools used in stoneworking, quarrying, and construction.
The Control of Vibration Regulations came into force in April 2005. They lay down specific exposure limit values and action values:
- For hand-arm vibration the daily exposure limit value is 5 m/s² A(8) and the daily exposure action value is 2.5m/s² A(8)
- For whole body vibration the daily exposure limit value is 1.15m/s² A(8) and the daily exposure action value is 0.5m/s² A(8)
Further more detailed guidance is published on the Safety Office website.
If there is a significant risk of HAVS, i.e. where an individual's vibration exposure exceeds 2.5m/s2, then a health surveillance programme via the University's Occupational Health provider must be arranged. The aim of this is to identify at an early stage any member of staff who may be showing medical signs of developing HAVS. If at any time between the routine checks, a member of staff notices any of the signs of HAVS, they should report it to their line manager in order that referral to Occupational Health can be organised and investigation of the equipment carried out by the School/Department.
Should a user of such equipment feel that performance has deteriorated in terms of vibration, they must report it at the earliest opportunity so that further investigations can be made. Also if a user notices any of the signs of HAVS, they should report it to their line manager in order that referral to Occupational Health can be organised and investigation of the equipment carried out by the School/Department.
Horseplay and practical joking is very dangerous in workshops. Never direct a jet of compressed air against anybody or yourself - this can be fatal. Ensure that flexible hoses used with compressed air are properly terminated, and carefully maintained. Where machinery is in use arrangements must be made so that a second person is within calling distance should an emergency arise.