Dogging (DG) flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Dogging HRW licence

In Australia, a high-risk work licence for dogging (class DG) is required to perform dogging work, or a trainee must work under direct supervision of a licensed dogger.

Primary duty of care

Under WHS law, a PCBU must ensure the health and safety of workers and others so far as reasonably practicable, including providing safe systems of work and training.

SWMS

A Safe Work Method Statement documents high-risk construction work steps, hazards, and controls; it must be prepared for crane and hoist operations involving loads near people or live lines.

Hierarchy of control

The order of risk controls: eliminate, substitute, isolate, engineering, administrative, then PPE; higher-order controls are preferred and PPE is the last resort.

Lifting gear inspection

Lifting gear must be inspected before each use and by a competent person at intervals not exceeding 12 months; defective gear is tagged out of service and not used.

Exclusion zone

A barricaded area beneath and around a lift path where no person may stand or walk; it prevents injury from a falling load or rigging failure.

Grade 80 chain

A high-strength alloy chain grade used for lifting slings; its working load limit depends on chain size and configuration and is stated on the sling tag.

Wire rope termination efficiency

A hand-spliced eye is about 90% efficient, a pressed ferrule about 90–100%, and a wire rope clip about 80% of the rope's breaking strength.

Safety shackle

A shackle with a bolt or nut pin that cannot rotate loose under load or vibration; preferred over a screw-pin shackle for permanent or vibrating lifts.

Hook safety latch

A spring-loaded device that closes the hook throat to prevent slings or attachments from slipping off; it must be functional unless the hook design prevents disengagement.

Eyebolt angular loading

Only forged eyebolts designed for angular loading may be used at angles; standard eyebolts are for vertical lifts only, and threads must be fully engaged.

Sling edge protection

Softeners or protectors placed between a sling and a sharp or abrasive load edge to prevent cutting, abrasion, or damage that reduces sling strength.

Spreader beam

A lifting beam used to keep sling legs vertical or to support a long load at two points, reducing inward forces and preventing load damage; its WLL must be verified.

Load weight formula

Weight = volume × density; for example, steel is about 7,850 kg/m³, concrete about 2,400 kg/m³, and water about 1,000 kg/m³.

Two-leg sling tension

For equal legs at angle θ from horizontal, tension per leg T = (W / 2) / sin θ, where W is the load weight.

Four-leg sling assumption

Unless the load is rigid and geometry guarantees equal sharing, assume only two legs share the load; calculate tension as for a two-leg sling.

Sling angle factor

The multiplier 1 / sin θ applied to load weight to find tension; values are 1.000 at 90°, 1.155 at 60°, 1.414 at 45°, and 2.000 at 30°.

Centre of gravity

The point where the load's weight acts; it must be directly below the hook and within the attachment points, or tension increases in the legs nearer the COG.

Unequal leg tension

For two legs at angles θ₁ and θ₂ from horizontal, horizontal components balance (T₁ cos θ₁ = T₂ cos θ₂) and vertical components sum to W.

Crane capacity check

The crane's rated capacity at the working radius must exceed the total load, including rigging weight and any dynamic or wind factors.

Designated signaler

The single competent person authorized to give signals to the crane operator at a time; the dogger may act as signaler if competent and designated.

Stop hand signal

Arm extended forward, palm down, held stationary; the operator must stop the crane immediately when this signal is given.

Emergency stop signal

Both arms extended forward with palms down, or a long whistle blast; any person may give it and the operator must obey immediately.

Radio communication protocol

Use an agreed channel and call signs, test before the lift, and if communication is lost the operator stops and holds the load safely until contact resumes.

Line of sight

The dogger must maintain a clear view of the operator; if line of sight is lost, a relay signaler or radio communication must be used.

Pre-lift briefing

A meeting before a complex lift to confirm load weight, rigging, crane capacity, path, signaler, and emergency procedures among all personnel.

Ground bearing pressure

The pressure exerted by crane outriggers on the ground; soft or sloping ground requires mats or cribbing, and the crane must be level.

Wind limit

The maximum wind speed at which a lift may proceed, set by the crane manufacturer; loads with large sail area are more affected and may require a lower limit.

Lift path control

The planned route for a load, kept free of obstructions and personnel; the load travels as low as practicable and never over people.

Trial lift

Lifting the load a few centimetres and holding to check balance, rigging, and stability before committing to the full lift.

Tag line use

A rope attached to a load to control rotation and swing; it must not be wrapped around hands or body parts, and the handler stays clear of the load path.

Vertical lift rule

Loads must be lifted vertically; side pulling or dragging can overload rigging, destabilize the crane, and cause load loss.