How to Record a Lift So the Next One Is Faster

Why this matters

Most of the time a rigging crew spends on a repeat lift is spent re-deriving things somebody already worked out. Not lifting, not rigging, deriving: what it weighs, where it picks from, how long the legs need to be, whether the machine reaches. A record that captures the answers without capturing the conditions the answers were true under does not shorten any of that, because nobody can tell whether the numbers still apply. This card works one job twice, once with no usable record and once with a good one, and lets the difference between the two visits decide which fields the form gets.

The two visits, and where the hours went

Same equipment, same location, same three-person crew, thirteen months apart.

The second visit ran 2.75 hours shorter, which is 42 percent of the first visit. That number decomposes exactly:

• 2.00 hours from not re-establishing the weight and pick points
• 1.00 hour from not re-rigging
• 0.50 hours from a faster setup with the sling lengths already known
• Less 0.75 hours added for a pre-lift meeting that did not exist the first time
• Net: 2.00 plus 1.00 plus 0.50 minus 0.75 = 2.75 hours

That added 0.75 hours is not overhead to be optimised away. On the first visit the plan was being assembled on the tailgate while the crew waited, which is why the derivation hours are so large and why the re-rig happened at all. The second visit's meeting is where the record turned into a plan, and it is the only line that went up.

The fields that produced the 2.00 hours

These are the ones about weight and pick points, and every one of them carries a condition rather than just a value.

Weight, and how it was established. Not "2,500 lb". The record reads: 2,500 lb, indicated on a load cell in the rigging, the cell's accuracy basis, and the date. A weight with no basis cannot be reused, because the next crew has no way to know whether it was weighed, calculated, or read off a submittal that excluded half the field additions. A sibling card covers why a published weight and an actual weight diverge and how the accuracy basis of a cell reading works.

What was removed or drained before the weight was taken. The condition, not the number. A unit weighed with its pan drained is a different object from the same unit weighed full, and the difference is invisible in the figure.

Pick points, and their standing. Which points, and whether they are engineered lifting lugs the manufacturer designated, or a bearing surface someone chose. That distinction is the whole reason this line saves time: an engineered lug is reusable information, and a chosen bearing surface is a judgement that the next qualified person may want to make again. Record which one you had, and record who made the call if it was a judgement.

Do the weighing with everyone clear of the load and out of the swing path, breaking the load free by inches and holding it still to take the reading. 29 CFR 1910.184(c) requires employees be kept clear of loads about to be lifted and of suspended loads, and a weighing pick is one.

The field that produced the 1.00 hour

The first visit's re-rig happened because the bridle went on and came up at 32 degrees to horizontal. Sling angle in this library is always measured from horizontal, which matters because half the trade quotes it from vertical and the two give reciprocal answers.

Leg tension is the share of the load on that leg divided by the sine of the angle to horizontal. For a rigid load on a four-leg bridle, plan on two legs carrying, not four, because a rigid object on four legs will typically bear on the two that come tight first and the other two ride along; that assumption is conservative and it is the one to use unless the load is known to be flexible enough to share.

• Share per carrying leg: 2,500 divided by 2 = 1,250 lb
• At 32 degrees to horizontal: 1,250 divided by sine 32 = 1,250 divided by 0.530 = 2,359 lb per leg
• At 60 degrees to horizontal: 1,250 divided by sine 60 = 1,250 divided by 0.866 = 1,443 lb per leg
• Ratio between them: 2,359 divided by 1,443 = 1.63 times

The crew stopped and re-rigged with longer legs, and the hour went there. The record now carries three things that make it unrepeatable: the sling lengths that produce an acceptable angle, the measured angle they produced, and the headroom available under the hook, which is the condition that forced the shallow angle in the first place. Sling lengths alone would not have helped; a future crew with less headroom would have hit the same wall.

Measure or verify the angle with the slings slack and the load on the ground, or compute it from the measured leg length and the measured headroom. Nobody stands under a suspended load with a protractor.

The fields that produced the 0.50 hours

Which sling went where, its type and length, the hitch used at each leg, and the hardware sizes with the capacities from their tags. A four-leg bridle rigged from memory takes a run of trial and error out of the sling rack; the same bridle written down goes together once.

Record the hitch explicitly, because a sling tag carries separate ratings for vertical, choker and basket, and reading the wrong column is the most common way a correctly-sized sling ends up overloaded. Note also that where a tag prints basket ratings at stated angles, those figures already contain the angle reduction: applying an angle factor on top of a tagged basket-at-60-degrees rating charges the same correction twice. That is a re-basing, not an addition, and getting it backwards leaves the leg undersized rather than oversized.

Photograph the tags while the slings are slack and out of service on the rack, not while they are in the rigging.

The fields that save no time and prevent a wrong reuse

These are the ones a crew leaves out because they did not cost anything the first time. They are what stops the record being used somewhere it does not apply.

• Machine configuration: boom length, counterweight, outrigger extension, quadrant of operation, and the radius at both the pick and the set. A capacity figure without its radius is not a capacity figure.
• Ground conditions: what mats were used, what bearing assumption they were sized against, and who owned that assumption. Ground support is engineering, and the record's job is to name the engineer, not to substitute for one.
• The exclusion zone and the swing path, including the arc of the counterweight tail swing, plus the access route the machine took to get there.
• What changed on the day, and why. The single most valuable field on the form, and the one most often blank. A plan that was amended in the field is more informative than one that was not.
• Who signed: the qualified person, the lift director, the operator.

What the second visit's 0.25 hours actually bought

It was not a formality. The crew walked the equipment against the record and found a field-installed economizer fitted at some point in the intervening year. The weight on the record was no longer the weight of the object.

That is the record working correctly. A good record is falsifiable: it says what the object was, in enough detail that someone can stand in front of the object and find the discrepancy in fifteen minutes. A record that only says "2,500 lb, four-leg bridle" cannot be checked against anything, so it gets believed instead, and believed is the failure mode.

The weight was re-established for the new configuration before anything moved, and the record was updated with a second dated entry rather than by overwriting the first. Two dated entries tell you the object changed. One overwritten entry tells you nothing.

The line the record does not cross

A record is history. It is not an authorization. The next lift gets its own plan, signed by its own qualified person, and the record's job is to shorten the derivation rather than to replace the decision. "We did it this way last time" is a reason to look at the record; it is never the reason a lift proceeds.

Two things make that concrete on the form. Nothing in the record is written as an instruction, only as an observation with a date. And every judgement line names who made it, so that a future reader sees a person's call rather than a fact. When the record says "bearing surface at the two frame rails, selected by the qualified person on this date", a new qualified person knows they are being handed a precedent to evaluate. When it says "pick at the frame rails", they are being handed an order from nobody.

How to verify the record is worth keeping

Hand it to someone who was not on the job and ask them three questions.

Can they tell what condition each number was true under? A weight with no date and no drained state, a radius with no outrigger extension, a sling angle with no headroom: each of those is a value that reads as reusable and is not.

Can they find something in it that is now false? If nothing in the record is checkable against the equipment, the record cannot earn trust and should not receive any.

Can they tell which lines are facts and which are judgements, and who made the judgements? If not, the record will be executed rather than evaluated, and the first time the object has changed, that is exactly how a stale number reaches a hook.

References

• 29 CFR 1910.184 and 29 CFR 1926.251, slings, including keeping employees clear of loads about to be lifted and of suspended loads, and sling identification and rated capacity markings
• 29 CFR 1926 Subpart CC, cranes and derricks in construction, for the qualified person, lift planning and configuration-specific rated capacity
• Sling and hardware manufacturers' tags and data for rated capacity by hitch and by angle
• See related: Why a Published Weight and an Actual Weight Diverge; What Removes Rigging Hardware From Service Permanently