Telephone: +61 2 8448 5500Technical Hotline: 1300 667 617

cmaa.com.au

WORKING UNDER OVERHEAD POWER LINES

SAFETY GUIDE

The information in this guide applies to the operation of plant, machinery and other equipment near overhead power lines, not limited to any type or class. Broadly speaking, the following are the guidelines for working under power lines: [9]

First make sure to follow the ABC rule when working near power lines:

Assess safe distances; Be Cautious and seek assistance from an

“Observer” or a “Spotter”; and Contact electricity supplier to seek advice.

Beware of ‘inattention blindness’ which develops when you are so focused on your work task, leading to temporary ‘blindness’ to what’s happening around you.

Know the exact height of your equipment — more specifically, the exact height when it is fully raised or extended.

The separation distances for operating plant, machinery or equipment, plant, machinery or equipment near overhead power lines must not be less than those shown in Table 1.

BACKGROUND

Concrete Masonry Association of Australia (CMAA) represents the concrete masonry manufacturers of Australia. Safety is a major issue and concern for our members.

This document stipulates the regulations and guidelines safeguarding the health and safety of all personnel against the risks of working near overhead power lines or associated machinery and equipment. It includes legislative obligations imposed by the Electricity (General) Regulations 2012 and Safe Works Australia concerning the proximity, or “unsafe distance” while working close to power lines and operating associated machinery. [1]

POWERLINE RISKS

The risk arises when a cable is struck by a machine or tool, which can cause fumes, hazardous fires and explosions to occur, resulting in serious injury, permanent disability or even death. Contact with live overhead power lines can lead to death and serious injuries.

Due to fatal hazards associated with power lines, it is crucial to communicate and follow all safety guidelines and regulations in the workplace to prevent such accidents from occurring.

Telephone: +61 2 8448 5500Technical Hotline: 1300 667 617

cmaa.com.au

Figure 2 : Common Power lines with difference in voltages [7]

PRELIMINARY PROCEDURES (PRE-JOB RISK ASSESSMENT)

The following considerations must be made prior to working under power lines to avoid severe penalties:

The location of the adjacent structure, its dimensional constraints and its functional utility (i.e. the purpose it serves, commercial, residential, industrial etc.).

The voltage capacity of the power line must be determined since it mandates the required safety clearance.

Any specifications of the power lines (including voltage capacity) can be obtained from the electricity regulators of the region. A list of these regulators are provided by Safe Work Australia – Electricity Regulators [4].

It is important to be aware of the voltages when working under power lines, especially between buildings as voltages may vary (see Figure 2). Safety precautions

vary under different voltage levels (see Table 1).

Figure 4 : Non-Contact High Voltage Tester attached to Hot Stick Extension [12]

HOW TO SAFELY DETERMINE THE VOLTAGE OF POWER LINES?

A high voltage detector is used by a qualified professional to determine the AC voltage within cables, cords, switches, circuit boards or similar equipment. A typical handheld prober can detect voltage between 30 to 122,000 volts, without contacting the conductor. High voltage probers typically have an audible indicator which beeps at higher frequencies and begins flashing bright warning lights when in range of higher voltages, to alert the holder. [10]

Figure 3 : Non-Contact High Voltage Tester [10]

Telephone: +61 2 8448 5500Technical Hotline: 1300 667 617

cmaa.com.au

Figure 5: Possible movement of power lines and machinery [6]

Figure 6: Conductor ‘sag or swing’ [3]

Minimum distance between moving

parts of machinery and the power line

Figure 7: Clearance zones for operating machinery in proximity to power lines [6]

NO SPOTTER REQUIRED FOR WORK WITHIN THIS AREA

SPOTTER REQUIRED FOR WORK WITHIN THIS AREA

RISK ASSESSMENT & SPOTTER REQUIRED

OBTAIN THISDISTANCEFROM TABLE 1

3 METRESFOR STABLE POLES8 METERS FOR TOWERS

8.4 METRES FOR STABLE POLES10 METRES FOR TOWERS

DANGERNO-GO ZONETo operate machinery with an elevating component such as cranes,

elevating work platforms and earthmoving equipment such as excavators the following safety requirements must be fulfilled:

The voltage of the power line must be identified;

A spotter (competent person who is suitably qualified by experience, training, or both with the sole duty of observing and warning against the unsafe approach of the crane, its lifting attachments or its load to power lines) carries out spotting duties always;

A documented risk assessment is carried out before any work commences, in consultation with all relevant parties involved in the work;

The electricity network operator is notified before commencing work; and

Any conditions specified by the electricity network operator or

Technical Regulator are complied with.

CRANES AND ELEVATING MACHINERY To operate machinery to the prescribed distances of the Regulations, you also have to factor in the following:

Power lines’ movement due to wind effects. Mechanical movement of machinery arm. Swinging of loads from momentum and wind effects.

Any breach of the prescribed clearances (see Table 1 below) can lead to [3]:

Risk of electric shocks for you and any other persons in the vicinity.

Release of toxic fumes. Hazardous fires and explosions.

These risks can result in serious injury, permanent disability or death and preventative measures must be carefully followed.

To estimate the height or voltage of the overhead electric lines, ask your Electricity Supply Authority for advice, or check Safe Work Australia - Electrical Safety Code of Practice for further information [2].

Telephone: +61 2 8448 5500Technical Hotline: 1300 667 617

cmaa.com.au

SAFE APPROACH LIMITS FOR PEOPLEThe minimum safe approach limit is measured from the closest conductor on the power line to the closest part of the person or an object held by the person. Subject to a documented risk assessment considering the movement of tools, materials and structures, it is possible to use reduced approach limits as indicated in Table 1 below.

WHAT TO DO IF YOU GET SHOCKED ON SITE?

Emergency rescue procedures must be developed, tested and practiced for each workplace or site. These emergency plans need to ensure:

1. Look first, don’t touch – the person may still be in contact with the electricity.2. Seek immediate medical attention, regardless of how minor the shock may be, call 000.3. Immediately report all electric shocks to the Health, Safety and Environmental (HSE) manager/site supervisor, irrespective of seriousness.4. To avoid further incidents, keep others a minimum of 5 m from the area electric shock. Take particular care if the victim is in contact with water or metal, which carries electricity. 5. In cases with high voltage energised electric lines, it is important to contact providers to cut off the electricity for the safety of all individuals on site. 6. Review and revise the on-site HSE policy where appropriate to avoid future incidents.

Even if you can’t see a physical injury, a mild electric shock might cause internal damage and medical attention is still required to assess whether the heart has been affected. All workers on site must be familiar with emergency procedures. [11]

Table 1: Safety Requirements for power lines [6]

For more information visit sa.gov.au/energysafe | 3

Safe Approach Limits for PeopleIn addition to the minimum clearance distances set out in the Electricity (General) Regulations 2012 for machinery and structures, there are safe approach limits for people working near powerlines as shown in Table 1 below (light green column).

The minimum safe approach limit is measured from the closest conductor on the powerline to the closest part of the person or an object held by the person.

Subject to a documented risk assessment taking into account the movement of tools, materials and structures, it is possible to use reduced approach limits as shown in Table 1 below (dark green column).

It is important when planning to carry out work near powerlines that the approach limits are taken into account. They may affect the work practices you need to use.

ScaffoldingThe Electricity (General) Regulations 2012 prescribe the legal clearances to powerlines from structures, which includes scaffolds. These clearances are dependent on the voltage of the powerline. This recognises that the higher the voltage, the more dangerous it is to work close to the powerlines, and therefore requires greater clearances. These clearances are shown in the Buildings column of Table 1.

Australian Standard AS/NZS 4576 – Guidelines for Scaffolding may in some situations define different clearances than the Electricity Regulations. This Standard uses the same clearances for all voltages and recommends that where practical the powerlines be de-energised when erecting scaffolds in close proximity to powerlines.

You must ensure that no part of the scaffold, persons, or other equipment or materials can breach the safe approach limits (discussed above), especially during the erection of the scaffold.

If these clearances cannot be achieved, it will be necessary to contact the electricity supply authority (usually SA Power Networks) to make arrangements for the safe completion of the works. This may require a Network Access Permit to be issued.

In some circumstances the clearances specified in AS/NZS 4576 may be less than those prescribed in the Electricity Regulations, in which case the prescribed distances of the Regulations must be complied with. Please refer to the ‘Building safely near powerlines’ brochure for more information on safe clearances for scaffolding.

Safe approach limit forpersons

Minimum distancebetween moving parts of machinery and the powerline

Image 3: Using tools in proximity to powerlines

Cranes

AS 2550.1 Crane Code. (Approved Code of Practice)Earthmoving machinery and Elevating Work Platforms

Machinery

Electricity (General) Regulations 2012 Schedule 5, Table 1 – Distance to operation of machinery, vehicle or vessel with elevating component or shear legs

Safe Approach Limits

Electricity (General) Regulations 2012 64(3) Safe Approach Limits

Buildings and Structures, including Scaffolds

Electricity (General) Regulations 2012 Schedule 1, Table 1

Voltage (in volts)

No Spotter

Spotter required

Risk assessment and spotter required

Approach limit – normal persons

Approach limit – with risk assessment

Horizontal direction

Vertical direction

240 6.4m 3.0m 1.0m 3.0m 1.0m 1.5m 3.7m

415 6.4m 3.0m 1.0m 3.0m 1.0m 1.5m 3.7m

7,600 6.4m 3.0m 1.5m 3.0m 2.0m 3.1m 5.5m

11,000 6.4m 3.0m 1.5m 3.0m 2.0m 3.1m 5.5m

19,000 6.4m 3.0m 1.5m 3.0m 3.0m 3.1m 5.5m

33,000 6.4m 3.0m 1.5m 3.0m 3.0m 3.1m 5.5m

66,000 6.4m 3.0m 3.0m 4.0m 4.0m 5.5m 6.7m

132,000 pole 6.4m 3.0m 3.0m 5.0m 5.0m 15m NA

132,000 tower 10.0m 8.0m 3.0m 5.0m 5.0m 20m NA

275,000 10.0m 8.0m 4.0m 6.0m 6.0m 25m NA

Table 1: Clearance distances from powerlines—to be taken from the position of the closest conductor

Telephone: +61 2 8448 5500Technical Hotline: 1300 667 617

cmaa.com.au

WORKING UNDER OVERHEAD POWER LINES

CHECK LIST

Have you contacted the electricity operator?

Did the operator approve the work being carried out?

Did the operator specify any operating conditions?

Have you checked the power line’s voltage and function (e.g. residential) and taken appropriate precautions?

Has a risk assessment been carried out?

Has it been documented and shared with all parties?

Are cranes or elevating machinery needed on site?

Have you noted the height of the machinery (fully extended)?

Is there enough distance away from power lines? (Refer to Table 1 in Power line Factsheet)

Is a spotter needed for the job?

Have you assigned a spotter for the site? (Refer to Safe Work Australia General Guide For Cranes)

ABC GUIDE:ASSESS SAFE DISTANCES

BE CAUTIOUS AND HAVE A SPOTTERCONTACT ELECTRICITY SUPPLIER TO SEEK ADVICE

PRELIMINARY PROCEDURES

SITE INSPECTION

Telephone: +61 2 8448 5500Technical Hotline: 1300 667 617

cmaa.com.au

REFERENCES

[1] Government of South Australia (2017), Electricity (General) Regulations 2012, Adelaide, Legislation Revision and Publication Act 2002

[2] Safe Works Australia (2014), Guide for working near low voltage overhead electric lines near structures[3] Safe Works Australia (2014), General guide for working in the vicinity of overhead and underground electric lines[4] Safe Works Australia (2014), Electricity Regulators [5] Safe Works Australia (2014), Electricity supply authorities [6] Be Energy Safe (2015), Working safely near overhead power lines, Government of South Australia[7] Be Energy Safe (2017), Building safely near power lines, Government of South Australia[8] Work Cover (2006), Code of Practice 2006: Work Near Overhead Power Lines, Gosford, Government of New South Wales.[9] Work Cover Tasmania (2009), A Guide to working safely near Overhead Power Lines, Tasmania, Government of Tasmania[10] Amprobe, 2019. Amprobe TIC 300 PRO High Voltage Detector for Safety[11] Health Direct Australia, 2019, Electric shocks and burns [12] Klein Tools, 2019. High Voltage Non-Contact Testers

Visit our website!

For more Fact Sheets Click here

MANAGEMENT OF SILICA DUST ON SITE

Telephone: +61 2 8448 5500Technical Hotline: 1300 667 617

cmaa.com.au

PCBU RequirementsWorkplace Health and Safety Laws stipulate that the employer or Persons Conducting a Business or Undertaking (PCBU) should control the hazards to minimise the risks from silica exposure[1].The silica related clauses can be found in Chapters 3 and 7 of the Work and Safety (WHS) 2011 Regulations[5]. The following regulations must be strictly followed to minimise the silica exposure level to workers:

BACKGROUND

Concrete Masonry Association of Australia (CMAA) represents the concrete masonry manufacturers. Safety is a major issue and concern for our members.

CMAA is aware of the safety concerns from activities associated with brick, block or paver cutting works, and encourage the industry to take steps to protect workers from exposure to respirable crystalline silica.

Crystalline silica is a common mineral that is contained in earth, sand, stone, concrete, and mortar. Respirable Crystalline Silica (RCS) are very small particles that can be created when cutting, sawing, grinding, drilling, and crushing concrete, brick, block, paver and mortar.

The silica dust hazard arises due to the inhalation and build-up of tiny silica particles in the lungs. Health Risks from Silica exposure include Chronic Obstructive Pulmonary Disease, Silicosis, Lung Cancer and Renal Disease.

This factsheet outlines the health hazards associated with silica dust, presents the key requirements from legislations and provide suggestions for alternative installation methods to control the silica component exposure level.

FACT SHEET

Identifying all silica hazardsThe PCBU must use a Safety Data Sheet (SDS) to identify and label silica hazards.

Labelling, recording and registering hazardous chemicals and SDSProper housekeeping, warning signage, restricting the time of exposure and rotation of staff away from dusty areas.

Managing the riskProper ventilation, use of Personal Protective Equipment and PCBU approved Respiratory Protective Equipment in accordance with AS/NZS 1715:2009 will help manage the risks associated with silica dust.

Health monitoring & records for exposed workersFor Workers exposed to silica over the Regulation Limits (Table 1), the PCBU must inform and provide the worker with a registered medical practitioner for health monitoring.

Reviewing control measures for silicaMinimise silica exposure[3]. Control measures can include and are not limited to:

Regular wet sweeping to prevent dust from spreading and accumulating.

Placing signs to remind workers to remove work clothes and leave them on site to prevent silica dust from spreading.

Vacuums used without HEPA filtration, dry sweeping or shovelling may cause dust to spread and accumulate increasing workers silica dust exposure.

Induction, information, training and supervision about silica Workers should be trained to understand:

How to identify different silica hazards

Control measures to prevent silica exposure and spreading

What to do in the event of silica exposure.

SUGGESTED ADJUSTMENTS TO INSTALLATION AND METHODOLOGY

Besides the implementation of WSH 2011 regulations 38 & 52 (Reviewing control measures), the following implementations could help reduce dust generation and increase safety within the Masonry industry:

Water suppression cutting systems that limit the amount of respirable crystalline silica that gets into the air;

High velocity low volume hoods (HVLV) for dust collection to: Ensure that silica concentration is within the WSH 2011

Regulation limits (Table 1); Reduce the need for site management issues (e.g. frequent

wet sweeping and congested site due to numerous exclusion zones.)

Reducing on-site cutting or drilling works by: Pre-cutting or drilling works in factories; Routing electrical wiring over the wall when possible; and Placing the correct type of ventilation on-site to exhaust silica-

contaminated air and avoid dust clouds.