Dogging (DG) cheat sheet

In Australia, dogging work is regulated under Work Health and Safety (WHS) laws; a dogger must hold a high-risk work (HRW) licence for dogging (class DG) or work under direct supervision while training.

AS 2550.1 (Cranes, hoists and winches – Safe use) sets general requirements; AS 1418 series covers crane design; AS 1353 covers flat synthetic webbing slings; AS 2318 covers wire rope slings.

WHS Act 2011 (model legislation) imposes a primary duty of care on PCBUs to ensure health and safety so far as reasonably practicable; workers must take reasonable care and comply with instructions.

A Safe Work Method Statement (SWMS) is required for high-risk construction work, including crane and hoist operations involving loads near workers or near live electrical lines.

The hierarchy of control (eliminate, substitute, isolate, engineering, administrative, PPE) must be applied; PPE is the last line of defence, not the primary control.

Lifting gear must be inspected before use and at intervals not exceeding 12 months for a major inspection; a competent person records results and tags defective gear out of service.

A load must not be lifted over people; exclusion zones are set beneath and around the lift path, and no person may stand or walk under a suspended load.

Design working load limit (WLL) markings must be legible on all lifting gear; unmarked or illegible gear is not to be used.

Incident notification: serious incidents (e.g., a load falling, crane collapse, or injury requiring immediate treatment) must be reported to the regulator as soon as practicable.

Chain slings are graded (e.g., Grade 80 or Grade 100); WLL depends on grade, chain size, and configuration (single, two-leg, four-leg) and must be read from the tag.

Wire rope sling WLL is reduced by termination efficiency: a hand-spliced eye is typically about 90% efficient, a pressed ferrule about 90–100%, and a wire rope clip termination about 80% of rope strength.

Synthetic webbing slings are colour-coded by WLL in some systems (e.g., purple 1 t, green 2 t, yellow 3 t, grey 4 t, red 5 t, brown 6 t, blue 8 t, orange 10 t), but the tag is the authoritative source.

Shackles: a screw-pin shackle must not be used where the pin can rotate under load; a safety (bolt) shackle is preferred for permanent or vibrating loads. WLL is stamped on the bow.

Hooks must have a functioning safety latch (mousing) unless the hook design prevents load disengagement; a hook should not be loaded on its tip or side.

Eyebolts: only forged eyebolts designed for angular loading may be used at angles; standard eyebolts are for vertical lift only. The thread must be fully engaged.

Sling angle affects WLL: as the included angle between legs increases, the load per leg increases; never exceed the rated angle marked on the sling assembly.

Softeners or edge protectors are used where slings contact sharp edges, corners, or abrasive surfaces to prevent cutting or abrasion.

Lifting beams and spreader beams are used to keep sling legs vertical or to support long loads; their WLL and configuration must be verified before use.

Load weight can be estimated from volume × density: steel ≈ 7,850 kg/m³, concrete ≈ 2,400 kg/m³, aluminium ≈ 2,700 kg/m³, water ≈ 1,000 kg/m³, timber ≈ 500–800 kg/m³.

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

For a four-leg sling, assume only two legs share the load unless the load is rigid and the geometry guarantees equal sharing; T = (W / 2) / sin θ for the two loaded legs.

Sling angle factor (load angle factor) = 1 / sin θ; common values: 90° = 1.000, 60° = 1.155, 45° = 1.414, 30° = 2.000.

For a single vertical leg, tension equals the load weight; for a single leg at angle θ from horizontal, tension T = W / sin θ.

Centre of gravity (COG) must be below the hook and within the sling attachment points; an off-centre COG increases tension in the legs nearer the COG.

For a load supported by two slings at angles θ₁ and θ₂ from horizontal, the horizontal components must balance: T₁ cos θ₁ = T₂ cos θ₂, and T₁ sin θ₁ + T₂ sin θ₂ = W.

A load-sharing factor may be applied for multi-leg slings, but the safe approach is to calculate as if only two legs carry the load when leg lengths or angles are unequal.

When a load is lifted by a crane, the crane's rated capacity at the working radius must be checked against the total load (load + rigging) plus any dynamic factors.

Only one person (the designated signaler) should give signals to the crane operator at a time; the dogger may act as signaler if competent.

Standard hand signals include: raise (arm extended upward, palm forward), lower (arm extended downward, palm down), stop (arm extended, palm forward, held stationary), emergency stop (both arms extended, palms forward).

A whistle or horn signal may be used: one blast = stop, two blasts = raise, three blasts = lower, long blast = emergency stop (verify site-specific signals).

Radio communication must use a clear channel, agreed call signs, and a test before the lift; lost communication requires the operator to stop and hold the load safely.

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

Signals must be clear, deliberate, and given from a position visible to the operator and clear of the load path.

Any person may give an emergency stop signal; the operator must obey it immediately.

Before the lift, the dogger confirms the load, rigging, and path with the operator and any other personnel; a pre-lift briefing is required for complex lifts.

A lift plan is required for complex or high-risk lifts; it documents load weight, rigging, crane capacity, path, personnel, and contingency.

The risk assessment identifies hazards (e.g., power lines, ground conditions, weather, public access, load instability) and controls using the hierarchy of control.

Ground bearing pressure must be checked for crane outriggers; soft or sloping ground requires mats or cribbing, and the crane must be level.

Weather limits: wind speed affects load control and crane capacity; the manufacturer's limit must not be exceeded, and loads with large sail area are more affected.

Exclusion zones are established around the lift area; barricades and signage keep unauthorized persons out.

The lift path must be free of obstructions and personnel; the load should travel as low as practicable and never over people.

Emergency procedures must be in place: a plan for power failure, rigging failure, or load loss, including a safe drop zone and communication.

Pre-lift checks include rigging inspection, load weight verification, crane capacity at radius, and confirmation of the signaler and operator.

The dogger directs the crane operator, attaches and detaches loads, and ensures the load is balanced and secure before lifting.

A trial lift (lift a few centimetres and hold) is used to check balance, rigging, and load stability before the main lift.

Tag lines are used to control load rotation and swing; they must not be wrapped around hands or body parts.

Loads must be lifted vertically; side pulling or dragging loads can overload rigging and destabilize the crane.

The dogger must never stand under a suspended load or place hands between the load and sling; use push sticks or tag lines instead.

When landing a load, the dogger guides it to a stable position, ensures the landing area is clear, and only then signals to lower and release tension.

Loads with an offset centre of gravity must be rigged so the COG is directly below the hook; use multiple attachment points or a spreader beam.

After the lift, rigging is inspected for damage, returned to storage, and any defective gear is tagged out and reported.