electricial house keeping

Version No.:1.0; Effective From: 01 July 2012 of 14

Printed copies are uncontrolled

Document Number # QH-GDL-275-1-1:2012

Guideline for Electrical Housekeeping State-wide Distribution

1. Purpose This Guideline provides recommendations regarding best practice for the correct use, storage and care of electrical equipment.

2. Scope This Guideline provides information for all Queensland Health employees (permanent, temporary and casual) and all organisations and individuals acting as its agents (including Visiting Medical Officers and other partners, contractors, consultants and volunteers). This Guideline refers to all works that have an electrical risk. The behaviours and methods described in this Guideline can be applied to all Queensland Health workplaces. It has application where ever electrical equipment, supplied by a plug and cord, is required to be used.

3. Related documents Policy and Standard/s:

• Occupational Health and Safety (OHS) Policy • Implementation Standard for Electrical Safety

Procedures, Guidelines, Protocols

• Procedure for Electrical Safety • Guideline for Trade Based Safe Work Method

Statement Forms and templates

• Safe Work Method Statement

Custodian/Review O fficer: Director, Safety and Wellbeing

Version no: 1.0

Applicable To : all Queensland Health staff

Approval Date: 01/07/2012

Effective Date: 01/07/2012

Next Review Date: 30/09/2014

Authority:

Lyn Rowland, Chief Human Resources Officer, System Support Services Division

Approving Officer

………………………………………

Name


Supersedes: 2-7-1#38 Electrical Housekeeping

Key Words: electrical housekeeping, electric shock, mechanical damage, double adaptors, lead placement, extension lead, patient areas, OHS

Accreditation References:

EQuIP and other criteria and standards

Queensland Health: Guideline for Electrical Housekeeping

Version No.: 1.0; Effective From:01 July 2012 of 14


4. Guideline for Electrical Housekeeping 4.1 Electric Shock 4.1.1 To appreciate the importance of the care and inspection of electrical

equipment in the workplace, it is useful to first consider how the potential for electric shock can arise.

4.1.2 Electricity is a useful tool and in normal circumstances is present in a controlled and safe fashion. Equipment is constructed to provide insulation and barriers to live parts. A quick visual inspection to ensure equipment covers or guards are intact and in place is necessary to confirm no access is possible to live parts.

4.1.3 Due to their portable and flexible nature, extension leads and the cords of portable appliances and tools, contribute to the majority of electric shock and injuries in the workplace. The vast majority of damage to this equipment is easily identifiable by visual inspection only.

4.1.4 When the protective sheath and conductor insulation on an extension lead is removed, as can occur when the lead is dragged over a sharp edge, it exposes the copper conductor and creates a hazardous situation. 4.1.5 Normally current flows from the power point via a three pin plug and is prevented from escaping the copper conductor by the insulation surrounding the wire. Now that the wire is exposed the electricity is free to seek alternative paths. 4.1.6 The way electricity is generated and transmitted in Australia means electricity is earth seeking. This means it has a preference form seeking out pathways to the ground you stand on or objects or things that are electrically conductive to ground. Unfortunately people can provide that path to ground when they come into contact with faulty electrical equipment. 4.1.7 The voltage supplied to the power point is greater than the voltages required to supply fatal levels of current flow in the human body. The electrical circuit in a situation where a person is receiving an electric shock is shown in the below diagram.




4.1.8 It is crucial to isolate supply to the victim of electric shock before approaching. 4.2 Mechanical Damage 4.2.1 The following requirements are in the Electrical Safety Regulation 2002: Cord Extension Sets and Flexible Cables

1. An employer or self-employed person must ensure that any extension set or flexible cable at the workplace is – (a) located where it is not likely to suffer damage, and (b) protected against damage.

2. In this section – damage includes damage by liquid. 4.2.2 The inclusion of this requirement in legislation reflects the experience and review of workplace incidents across a wide range of industries and environments. The single most effective measure in the workplace to prevent electric shock or burns is to prevent damage to leads and plugs. 4.2.3 Some key points to consider for the “health” of leads and portable appliances are:

• lead placement

• use of Residual Current Devices (RCDs)

• protective devices such as lead hooks, ramps or covers

• correct removal of plugs from power points

• storage

• lead lengths

• use of heavy duty sheathed cables




• uncoiled use of leads

• before next use visual inspections

• test and tagging

• maintenance. 4.2.4 Extension leads are to be considered for temporary use and should not take the place of power points installed in a convenient location for the longer term. This approach gives the benefit of RCD protected power points and eliminates the use of an extension lead that can contribute to a trip or electric shock hazard. If an extension lead is required, select the shortest suitable length and fully uncoil the lead. 4.3 Double Adaptors 4.3.1 Double adaptors shall not be used in the workplace as they do not provide overload protection and are readily dislodged. 4.3.2 The installation of power points is required to prevent an over reliance on power boards. 4.4 Lead Placement 4.4.1 Consideration should be given prior to the use of an extension lead or appliance, to run the lead to minimise trip hazards and the likelihood of mechanical. 4.4.2 Some situations that place leads at risk of damage are:

• trafficable areas, leads run over by vehicles or other equipment

• placing leads in doorways or the middle of hallways

• running leads through closable windows or doors

• draping leads over the sharp edges of materials or equipment

• the placement of leads on hot surfaces such as lamps, etc.

• inappropriate use of power tools, entanglement with moving parts

• whipping out leads instead of removing the plug in line with the pins

• use of coiled leads that creates overheating

• excessive lead lengths causing voltage drop and overheating

• use of leads as tie downs or ropes. 4.4.3 If a lead is required to be run across a trafficable area, the lead must be protected from mechanical damage. This can be done by using a lead cover or a lead stand. 4.4.4 Tunnel tape is not to be used in this instance as it does not protect against mechanical damage. Tunnel tape can be used to tidy and constrain leads to prevent entanglement or trip hazards. Place leads in the corners of rooms




and away from the centre. Once the route is decided leads can be covered by lead covers, some of which are suitable to support vehicle traffic. 4.4.5 An example of a lead cover and tunnel tape are shown below.

4.4.6 To prevent a trip hazard when a lead crosses a door way a lead stand can be employed to lift the lead clear. Not only can this arrangement facilitate clear access for others it can also remove the lead from the risk of damp areas. 4.4.7 A non-conductive lead stand is preferable. An example of this is shown below.

4.4.8 The use of an opening such as a window or door can provide ease of access for an extension lead, however, if the door or window is blown closed or shut with force, damage to the lead can occur. Devices, some of which are lockable to maintained authorised access, can be placed to keep doors ajar the minimal distance to allow a lead entry.




4.4.9 A similar approach can be taken with a window using any suitable material to prevent full closure. If damage to a lead occurs the possibility of metal framed doors or windows becoming live exists and as such the above measures should be considered. 4.4.10 Material or equipment that is the subject of the work may include burrs or sharp edges that can damage the lead also. The use of lead hooks or padding that covers the edges of equipment is recommended. 4.4.11 The plastic sheath and conductor insulation on flexible cables, such as extension leads, begins to melt and degrade from around seventy five degrees Celsius. Some possible sources of temperatures exceeding this in the workplace include lamps and light fittings, hot plates, ovens, and tools such as heat guns, soldering irons and welders. 4.4.12 Leads shall be placed clear of sources of heat and a constant awareness maintained of lead placement and heat sources. 4.4.13 Power tools and electric appliances require due care and appropriate use to ensure continued safe functionality and performance. When using items with exposed moving parts or blades ensure the power cord is prevented from coming into contact with these by draping clear of the cutting area. 4.4.14 Only use tools that have all guards and covers in place and have a current testing tag in place. 4.4.15 Maintenance and cleaning of equipment is important as a build-up of contaminates in equipment can provide a conductive path to live parts and the frame of the tool. For example, carbon and dirt build up within a motor housing could provide a conductive path from the exposed metallic parts of equipment to live internal parts. 4.4.16 When cutting ensure there are no leads below the job hidden out of view or concealed in wall cavities. Avoid penetrating walls vertically or horizontally from electrical equipment such as light switches or power points. An example of areas to avoid is shown in the diagram below.




4.4.17 When removing or inserting a plug it is recommended to switch the power point off first. This will help reduce the risk of electric shock at the moment of connecting the lead if the plug is damaged. When removing the plug ensure removal is by gripping the plug and withdrawing from the power point in a straight fashion in line with the plug pins. This will prevent bending or deforming of the plug pins. 4.4.18 Leads shall not be removed by whipping or pulling on the lead as this can damage conductors, such as protective earths, and bend or brake plug pins. Under no circumstances shall an extension lead be used as a rope or tie down.




4.5 Extension Leads 4.5.1 Overloading of extension leads causes excessive heat that can break down the insulation of cables and pose a fire, as well as an electric shock hazard. Excessive heat can be caused by voltage drop across leads that are too long for the conductor size or by the use of leads that are coiled. 4.5.2 Leads shall only be used when fully uncoiled and they must not be wrapped around metal poles as this will strengthen the damaging affect. 4.5.3 The use of power boards should be limited as far as possible while preventing the practice of cascading boards. That is plugging multiple boards into each other to gain more power points. 4.5.4 Double adapters are prohibited from use as they do not provide for overload protection. 4.5.5 Tasks related to the use of power tools or maintenance and construction require the use of a portable RCD. 4.5.6 In an office environment the use of an overload protected power board can be appropriate. Maximum lead lengths are detailed in the table below, which is an extract from AS/NZS 3199:2007 Cord Extension Sets.




4.5.7 For hostile environments, such as workshop or construction areas, heavy duty sheathed leads shall be used. 4.5.8 Whilst not in use leads are to be stored in locations free from the risk of mechanical damage or the ingress of fluids. The practice of storing leads amongst other tools is to be discouraged as vibration and movement can cause tool edges to damage sheath and insulation. 4.5.9 When in use or in storage care shall be taken to ensure crimping or sharp bends of the cable do not occur. A large radius bend of the cable will prevent damage to the conductors. A general rule is an internal radius of six times the diameter of the lead. Damaged conductors may lead to faults such as broken protective earth conductors or hot spots resulting from high resistance.




4.6 Before Next Use 4.6.1 A visual inspection of electrical equipment and leads can identify the most common faults. These faults are either damaged or removed covers or guards and damaged insulation to cords and plugs. 4.6.2 Before connecting equipment to supply it is recommended than an inspection is conducted. 4.6.3 Damaged equipment is to be removed from service as per local arrangements. This would normally be the attachment of an out of service tag and notification to the supervisor of the work area. 4.6.4 Most electrical equipment within Queensland Health will have attached a test tag. This may not be the case in a service or office area with total RCD protection that has been the subject of a documented Test and Tag review. This tag will display the date of test or when the next test is due. 4.6.5 Only use equipment that is within a current test period or, in an office or service work area, protected by an in test RCD. An example of a test tag is shown below.




4.7 Patient Areas: Body-Protected or Cardiac-Protected 4.7.1 Areas of health facilities where patients interact with mains powered medical electrical equipment are required to have prescribed electrical safety features. These areas can include bathrooms, waiting and consulting rooms, wards, theatres, imaging and dialysis locations. 4.7.2 The safety features required determines how the electrical equipment, such as power points, are installed and in the case of cardiac-protected areas, the requirement for a supplementary earthing system. 4.7.3 Both body-protected and cardiac-protected areas will be identified by the signs shown below. To comply with the relevant electrical standards periodic testing is done and the test date and next test date are displayed in the upper right hand corner of the sign.




4.7.8 To assist in maintaining the integrity of the electrical safety features of patient areas it is important that some basic precautions are taken. The following can support electrical safety in patient areas:

• use dedicated beige power points for cleaning purposes

• do not use double adaptors or extension leads in patient areas, particularly from hallways to patient locations or between patient locations

• visually inspect electrical equipment before connecting to supply in patient areas

• familiarise yourself with the operating instructions for electrical medical equipment and any requirement to attach an equipotential bonding conductor in a cardiac-protected area, e.g. bonding an electrically operated patient bed

• generally discourage the use of patient or visitor personal electrical equipment in patient areas and ensure any proposed use is dependent on the equipment being tested and tagged.




5. Definition of Terms Definitions of key terms are provided below. Term Definition / Explanation / Details Source

Electrical Equipment Is any apparatus, appliance, cable,

conductor, fitting, insulator, material, meter or wire:

• used for controlling, generating, supplying, transforming or transmitting

electricity at a voltage greater than extra low voltage; or

• operated by electricity at a voltage greater than extra low voltage; or

• operated by electricity of an extra low voltage, if the equipment forms part of

an electrical installation located in a hazardous area; or

• that is, or that forms part of, a cathodic protection system.

However, ’electrical equipment’ does not include any apparatus, appliance, cable,

conductor, fitting, insulator, material, meter or wire forming part of a vehicle if:

• it forms part of a unit of the vehicle that provides propulsion for the vehicle; or

• its source of electricity is a unit of the vehicle that provides propulsion for the

vehicle.

Electrical Safety Codes of Practice 2010 – Electrical Work

Energised Means energised by electricity. Electrical Safety Act 2002 (S2)

Isolation Point Means the point, or one of many points, used to isolate electrical parts.

Electrical Safety Code of Practice 2010 – Electrical Work

Live (Alive) Means connected to a source of electrical supply or subject to hazardous induced or capacitive voltages. Generally, ‘live’ refers to a conductor or conductive part intended to be energised in normal use, including a neutral conductor and conductive parts connected to a neutral conductor.

Electrical Safety Code of Practice 2010 – Electrical Work

Residual Current Device As defined under the Regulation and Standard. A mechanical switching device designed to make, carry and break currents under normal service conditions, and to cause the opening of the contacts when the residual current attains a given value under specified conditions. The RCD may be fixed or portable (PRCD). RCDs are classified in AS/NZS 3190 according to their rated residual current as follows:

Electrical Safety Regulation 2002 Part 5 (S83 – Safety Switch)

AS3760-2010




(a) Type I : ≤ 10 mA;

(b) Type II : > 10 mA ≤ 30 mA;

safety switch means a type 1 safety switch or a type 2 safety switch.

Test and Tag The regular inspection, testing and tagging of electrical equipment.

AS3760-2010

6. References and Suggested Reading Nil.

7. Consultation (optional) Key stakeholders (position and business area) who reviewed this version are:

• Principal OHS Advisor, Safety and Wellbeing

8. Guideline Revision and Approval History Version No.

Modified by Amendments authorised by Approved by

1.0 L O’Neill – Principal OHS Officer – Safety and Wellbeing

G Easterby – a/Director Safety and Wellbeing


electricial house keeping

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