Preventative maintenance for electrical safety

Jim Wallace, research and technology manager at Seaward Electronic, explains the importance of ensuring the safety of electrical equipment used in the workplace.

Jim Wallace, research and technology manager at Seaward Electronic, explains the importance of ensuring the safety of electrical equipment used in the workplace.

Although there are legal duties on manufacturers and suppliers covering the integrity of new electrical or electronic equipment, responsibility for the safe operation of equipment in the workplace rests firmly with the employer.

The Health and safety Executive (HSE) claims that nearly a quarter of all reportable electrical accidents involve portable and transportable electrical equipment and reports around 1,000 workplace electrical accidents each year.

As an example, in 2003/2004, electric shocks caused 14 deaths and 148 non-fatal major injuries to employees in the UK.

In addition, there were nearly 400 further cases where electricity related injuries resulted in the loss of three days or more work.

Fires started by poor electrical installations and faulty appliances also cause deaths and injuries - for example, faulty equipment and leads have been know to cause over 6,000 separate fires a year.

TESTING TIMES.

The Health and Safety At Work Act 1974 puts a duty of care upon both employer and employee to ensure the safety of all persons using the work premises, but the particular legal requirements relating to the use and maintenance of electrical equipment are contained in the Electricity at Work Regulations 1989 (EAWR).

Regulation 4(2) of the EAWR requires that all electrical systems be maintained, so far as reasonably practical, to prevent danger.

This requirement covers all items of electrical equipment including fixed, portable and transportable equipment - essentially anything connected to a building's electrical system with a plug.

PASS OR FAIL.

Although people carrying out the testing of portable electrical equipment should be appropriately trained for this work, many field service organisations and contracting companies have set up specialist portable appliance testing operations.

Other organisations have responded with the introduction of in-house testing protocols managed by maintenance managers, safety engineers and site electricians or facilities management personnel.

Planned and proactive safety policies must be capable of detecting potential problems with electrical appliances before they occur and this is the role of preventative maintenance programmes.

The majority of equipment defects can be found during visual inspection - the HSE says that just looking can identify 95% of faults or damage.

For example, a detailed examination by a competent person is likely to eliminate hazards caused by cable or plug damage, faulty wiring or other obvious signs that the equipment's condition could create faults or a danger to users.

However, to identify all potentially dangerous faults, visual inspection needs to be linked with a programme of periodic inspection and testing that is capable of revealing any 'invisible' electrical faults such as earth continuity, insulation integrity, correct polarity, unacceptable earth leakage and other potential problems.

Clearly such combined inspection and testing measures should be appropriate to the particular risk posed by the equipment and its environment.

This means that maintenance procedures in some commercial environments might be required less frequently than in other high risk environments such as industrial premises and construction sites - but will still be needed to verify safe working conditions.

For example, smaller offices or workplaces with only a few electrical appliances, and a staff of limited technical ability, might be regarded as relatively low risk environments.

Here a responsible attitude might be regarded as a regular process of formal user checks and visual inspection, combined with some limited periodic testing.

A different view, however, might need to be taken by a large organisation, with different departments and having many different types of electrical equipment used by staff.

In this case, ensuring the safety of appliances may not only be a matter of ensuring the correct test equipment is available, but also having the ability to show that the right tests have been performed at the right time in the correct sequence - with records of test levels and results.

Overall frequency of inspection and testing of equipment will depend on whether the electrical items are rated as Class I or Class II and in what environment they are used.

For example, an office kettle might require a visual inspection every six to 12 months and combined inspection and testing every one to two years.

On a broader front, inspection and testing of some construction equipment might be advisable every 1-3 months, but this can range to up to 12 monthly intervals for some industrial locations, commercial kitchens and other workplaces, to 24 months and above for hotels, some offices and shops.

TESTING, TESTING.

Cost effective maintenance of portable electrical equipment can therefore be achieved through a combination of user checks, formal visual inspection and electrical testing.

Combined inspection and testing programmes require greater level of competence than for inspection alone.

However, a range of portable appliance testers (PATs) are available that make the in-service safety testing process safe, fast and easy to carry out.

Test instruments are available which range from the relatively simple to operate pass/fail checkers which will carry out some of the basic safety checks on equipment to provide an immediate 'go/no go' display.

However, for more comprehensive test requirements, microprocessor controlled testers are available that combine user-friendly operation with a whole range of other features for particular test demands or routines.

The incorporation of Bluetooth technology in modern testers allows the wireless connection of bar code scanners, label printers and other accessories - allowing totally cable-free testing, without the cumbersome and constant plugging in and unplugging of leads and cords.

In addition, the latest generation PAT testers also have the facility to record the results of other safety management data including emergency safety lighting conditions, or condition of fire extinguishers, for example, as part of more comprehensive safety equipment audits.

Although there is no formal requirement in the EAWR for records, the HSE does recognise that some records of maintenance and test results is a useful management tool for reviewing schemes and demonstrating that safety policies have been enforced.

The use of computerised portable appliance testers also enables test data to be transferred directly from the instrument to a PC-stored database allowing an automatic update of test records, the generation of test reports and advance testing schedules.

More recently a new safety-testing concept has been introduced to help those responsible for ensuring the safety of electrical equipment in the workplace to improve their productivity and effectiveness.

The 'PATSolutions' approach seeks to streamline the selection of integrated portable appliance testing systems by bringing different test elements into distinct product packages.

Linking hand held test instrumentation with new technology and service support, different packages have been introduced to meet the different test system needs of facilities and safety managers or service engineers that carry out in-house electrical safety testing.

Back to top