Site Safe Electrical Safety on Construction Sites 3

Question 1

What is the standard single-phase mains voltage in New Zealand?

Accepted Answer

230V AC

Answer

New Zealand's standard single-phase mains voltage is 230V AC at 50Hz, which is potentially fatal if a person receives a shock.

Question 2

What does 'double insulation' mean when it is marked on a power tool?

Accepted Answer

The tool has two independent insulation barriers between live parts and the user

Answer

Double insulation means the tool has two separate layers of electrical insulation protecting the user, so if one layer fails the second still provides protection.

Question 3

Under the Health and Safety at Work Act 2015, who holds the duty to manage electrical risks on a construction site?

Accepted Answer

All PCBUs with management or control of the worksite

Answer

The HSWA 2015 places a duty on all PCBUs (persons conducting a business or undertaking) with management or control of a worksite to manage all risks, including electrical hazards.

Question 4

How close to a located underground cable can you continue to use mechanical excavation equipment?

Accepted Answer

Up to 300mm from the cable

Answer

Once within 300mm of a located underground cable you must switch to hand digging only to avoid striking the cable with mechanical equipment.

Question 5

What must happen before a crane or elevated work platform operates near overhead power lines?

Accepted Answer

Stop work and contact the network operator to arrange isolation or line protection

Answer

When overhead power lines are within or near a plant work zone, work must stop and the network operator contacted to arrange line isolation or physical protection before operations resume.

Site Safe Practice Test

Site Safe Practice Test

Site Safe Electrical Safety on Construction Sites 3