CONTENTS
What's it all about?
Suggested procedures
The formal visual inspection
More visual considerations
The Electronic Tests
Glossary of terms
Further references
Web site links for PAT testing training courses
Sample record form (App A)
Suggested retest intervals (App B)
Fuse rating guide
Portable Appliance Testing
The Electricity (Factories Act) Special Regulations 1908 & 1944
Have been replaced by:
The Electricity At Work Regulations (1989)
These came into force on 1st. April 1990
If they believe the regulations are not being complied with inspectors are authorised to issue a prohibition notice with immediate effect. This would prevent any further work from taking place on the site. An improvement notice would be issued, and if the requirements of this were not complied with then the case would become the subject of a prosecution.
Maximum penalties of fines up to £5000 and/or up to six months imprisonment are in the event of a successful prosecution under any Health & Safety statute.
The Health & Safety at Work Act 1974 has allowed for penalties up to £20,000 fines since 1992
Offences heard by the Crown Courts have unlimited fines with a possible two year prison sentence.
The surest way to enable yourself to demonstrate that you are taking the regulations seriously, is have in place a record-keeping system which is properly maintained. This may be electronic or paper based, and should show a history of all PAT Testing activity.
T
his manual is designed to enable people who have not received any formal training in electrical work, to carry out visual inspection and possibly electronic testing, of portable appliances, and assess the risk of danger to the user of that appliance.
It must be stressed that visual inspections, without dismantling will not capture every potential defect. This is why, in addition to regular visual inspections appliances MUST receive a full electronic test using a purpose designed PAT meter. Having said this however, it should be borne in mind that, in general, over 85% of faults are discovered during the visual inspection stage.
In the workplace it is a legal requirement that a system of preventative maintenance exists which is “effective in preventing any appliance from becoming a danger to any person”.
Regulation 4(2) States:
"As may be necessary to prevent danger, all systems shall be maintained so as to prevent, so far as is reasonably practicable, such danger."
To this end the person or persons using the appliance should be able, with suitable training, to recognise visual signs that any appliance is not in sound condition.
Types of equipment covered includes
Portable Appliances:
An appliance which is intended to be moved while in operation or an appliance which can easily be moved from one place to another while connected to the supply, e.g. toaster, food mixer, vacuum cleaner.
Transportable Equipment:
This is equipment which is either:
18kg or less in mass and not fixed, e.g. Electric heater, or
Equipment with wheels, casters or other means to facilitate movement by the operator as required to perform its intended use.
Hand-held Appliances or Equipment:
This is portable equipment intended to be held in the hand during normal use, e.g. hair dryer, drill, soldering iron, kettles.
Secondary equipment or appliances:
This equipment has a mass exceeding 18kg and is not provided with a carrying handle, e.g. refrigerator, washing machine.
Extension Leads:
These should use three core cable even if used to feed a class 2 appliance.
Extension Leads should be tested as for class 1 appliances but should additionally include a polarity check.
It is recommended that the maximum length of extension leads should be limited to the following:-
Lead cross sectional area (sq mm) Maximum Length
1.25 12 metres
1.50 15 metres
2.50 25 metres
All extension leads should be used in conjunction with a 30mA RCD
New Equipment:
There do not appear to be any set rules relating to new items which are brought onto the site.
The most widely practiced procedure appears to be that new items are given only a visual inspection an then recorded in the system so that when they are a year old they are marked for full testing. Traditionally this was adopted for fear that testing by an agency other than the manufacturer may invalidate any existing warranty.
However, it may be considered that the possibility that the item may have been damaged in storage or delivery, or stored in an unsuitable environment might be grounds for full testing before issue to a user.
Another consideration of course is that in the event of a fault, the warranty would cover the appliance – but not the user L
SUGGESTED PROCEDURES
he usual practice, if the site is large, is to circulate a form onto which the details of each item are entered by the manager of each department. This form can then form the basis of a paper or electronic system as required. A suitable form is reproduced in appendix A. and may be copied if required.
If the site is small and there are few items to keep track of, it is still probably wise to maintain records of some sort. It would, for instance provide a check that no items were missed. Also items imported onto the site would be identifiable due the labelling system.
Also if your system provided evidence of very few faults being identified, this might be justification for extending the period of time between tests.
The normal approach is for each appliance to be numbered, and this is the appliance number that is entered on the record card and the label, which is to be attached to the appliance. If a serial number is also evident on the appliance then this can be useful for identification purposes, but don't rely on every appliance having a manufacturer's serial number easily seen.
The Class section of the form refers to whether the appliance is Class 1 or Class 2. This will be explained in the section under check procedures. For the visual check there is only one part of the form to complete, the others are completed at the time of the electronic test which often, but not always has a longer retest interval than the visual.
Labels can be purchased from several sources, and these days show the date of the next test due as well as the date the item was last tested. The purpose of showing the date of the next due test is for the benefit of users of the appliance.
Also bar coded labels are becoming popular, particularly when there are large numbers of appliances and electronic systems are favoured. Bar coding also helps maintain uniformity of tests applied and meaningful comparison of results.
Frequency of testing
Having completed all the forms, a decision must be made regarding the frequency of testing.
Appendix B gives the suggested retest intervals for various items.
This can be used as an initial guide, but experience may, in the fullness of time, indicate that there is a need to modify the programme according to the number and type of faults found. Other factors to bear in mind when considering retest intervals include:
1/ Working environment
(Dampness, Dust, Likelihood of mechanical damage)
2/ Whether equipment is hand held
3/ Age and general condition of the equipment
4/ Potential for misuse
5/ Manufacturers recommendations
6/ Modifications which may have been made to the equipment
It should be noted that on building sites or other harsh environments any programme of planned maintenance should be supplemented by a daily visual inspection of the plugs and leads of all hand-held tools.
THE VISUAL INSPECTION
Appliances are (for our purposes) either Class 1 or Class 2. The difference is as follows:
Class 1 Appliances use a Circuit Protective Conductor or Earth wire.
This means that this earth wire is connected to any exposed metal parts of the appliance. Hence if the basic insulation fails the user is protected by the fact that the exposed parts of the appliance cannot become electrically charged above earth potential. Modern installations would detect this failure and immediately operate an RCD to interrupt the supply, whereas on older installations a fuse should blow in this situation. (RCD's protect people whereas Fuses protect circuits).
It is essential therefore that the condition of the earth wire is sound, and the earth bonding test is designed to check this.
It is also recommended that when fitting or removing plugs and sockets the earth lead should be wired first and removed last.
Class 2 Appliances however, do not use this Earthing technique, so the mains plug will be connected to only two conductors, neutral and phase (Live).
Appliances designed to operate without an earth connection will be constructed with supplementary insulation in addition to the basic insulation provided in Class 1 appliances. Appliances designed to operate in this manner will (or should) be marked by the manufacturer with the "double insulated" sign. (Two squares, one inside the other).
As far as the visual inspection is concerned, the proce...
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