Spread the slings.
Watch it get heavier.
Every rigger has been told flatter is heavier. This is what it looks like. Drag the spread of a two-leg bridle and the pull in each leg climbs in front of you. Change the hitch and the slings re-rig in 3D. Knock the load off balance and watch it tip.
Teaching tool. The sling tag, the manufacturer's instructions and your site's lift plan govern the real lift. Nothing on this page is a substitute for any of them.
Drag to look around · pinch to zoom
× the load's weight
At this angle each leg carries 0.71× the load's weight. Flatter = heavier.
Two legs hanging straight down would each carry exactly half. Everything above that is the angle charging you for it.
The lawful reduction is not on this page. It comes from your sling's tag, the manufacturer's instructions, or OHSR Table 15-3 — read the tag.
OHSR 15.34 · Table 15-3Colour on the slings here shows how hard each leg is pulling — it is not the sling's rated colour code.
The sway and settle in the picture are illustrative — the figures are the static loads your tag governs.
Straight from the hook to a fitting on the load. Nothing grips the load, so it can rotate — you need proper lifting points.
The centre of gravity sits under the hook. The load comes up level.
Four things
this rig teaches.
Each control on the tool exists because riggers get hurt when it is wrong. Here is what each one is for, and where the rule lives.
01 — The angle is a multiplier
Two legs hanging dead vertical each carry half the load. Spread them and each leg has to pull sideways as well as up, so the pull goes up — the same slings, the same load, more force. Past 120° included, every leg is carrying more than the whole load weighs. The physics on this page is jurisdiction-free arithmetic. The lawful capacity reduction is a different thing — it lives on your sling's tag, in the manufacturer's instructions, or in Table 15-3.
02 — The hitch changes everything
Vertical is the sling's full rated pull, but nothing grips the load. Choker bends the sling around itself to bite the load — it grips, and the tag shows a lower figure than vertical. Basket puts two parts of the sling under the load, so each part carries half of what a single leg would, and the tag's basket figure is higher. Pick the hitch for the load, the lifting points and the conditions — not for what is nearest to hand.
03 — Hook over the centre of gravity
A load hangs with its centre of gravity directly under the hook. Every time. If you rig to the middle of the steel and the weight is not in the middle, the load will roll until it is — and the leg on the heavy side takes the bigger share. Notice what happens when you flatten the angle as well: with the hook low, the same offset tips the load much further.
04 — The assembly is only as strong as its weakest part
The number on the sling is not the number for the lift. Shackle, master link, hook, the lifting point on the load itself — the whole arrangement is limited by whichever component is weakest, and it is your job to know which one that is. Rigging is done by, or under the direct supervision of, qualified workers who know the rigging in use and the Board's code of signals.
Oakridge, 4 October 2024. A bundle of pipe fell roughly 150 feet. Chains had been used instead of nylon slings. The rigger questioned it, was told chains were commonly used, and — in the investigation's words — "lacked the confidence to decide not to proceed." The crane operator saw the rig and allowed the lift.
Every person on that lift had the authority to stop it. Nobody used it. That is why our course assesses stopping as its own skill, and why this tool argues with you when you rig a bundle badly. For loads of two or more pieces over 3 m, the regulation calls for a two-leg arrangement with each sling double-wrap choked.
Built for British Columbia.
Assessed by a rigger.
Online theory you can do at 6am, then a real practical assessment with a qualified rigger — sling and hardware identification, inspection to the removal criteria, angles, hitches, centre of gravity, and the full Figure 15-1 signal set. A record of training and practical competency assessment. Your employer decides whether you are qualified; we give them the evidence.
There is no rigger certificate, licence or ticket in British Columbia, and WorkSafeBC does not approve, certify or accredit rigging courses or providers. Anyone who tells you otherwise is selling something. OHSR 15.2 · OHSR 1.1