One of the practices that we use in the construction field with
regularity involves choking, or simply slinging boxes of items up. The rationale
used is commonly that the sling governs the rating on the lift. I would like to
challenge this line of thought. Not only do I think the practice is dangerous,
I think it’s flat illegal in the United States. OSHA addresses this matter
several times in the Letters of Interpretation regarding 1926.251.
Special custom design grabs, hooks,
clamps, or other lifting
accessories, for such units as modular panels, prefabricated structures
and similar materials, shall
be marked to indicate the safe working loads and shall be proof-tested prior to
use to 125 percent of their rated load.
If we start with the highlighted section, we can clearly see OSHA wants all lifting items rated and tested. Does anyone think the black box is rated or tested? Is it marked for it’s capacity? In this case, if we presume those are 2” straps rated for 6400 in a vertical and 5000 lbs in a choke, are we safe to assume that we can put 10,000 lbs in that box and fly it? A ¾ ton truck fully loaded in that box and we are good? And it still has the 3:1 safety factor (ASME B30.20 requirement) so it shouldn’t fail until we put three of them in the box? If the box fails, do the slings stand up to the shock loading? You can see the deflection in the box as it is currently loaded. Are we at only 33% of the boxes ultimate capacity as it is rigged? You can stop me at any point where you agree that the practice is flawed.
If the load is contained in the box, then the box must be
rated. The concept is simple once you hear or see it. The lift is a chain of
items that must be rated and planned. The footing of the crane is commonly
1.65x the highest loading possible. Same for the crane structure. The hoist
line is 5x. The brakes on a crane hoist are commonly 125% of the rated line pull with 2 of them in
operation. The slings are a minimum of 4x. But then we want to put a box in the
chain that isn’t even rated? All of the effort to get here with safety, only to set it aside to save $100? I should note that many of these boxes are rated
at 1500 lbs when lifted by a forklift. This doesn’t even have support where the
tines would be. The reasoning is flawed. The box has to be rated. And this isn’t
just me making the argument. OSHA makes it too in the following Letter of
Interpretation:
Question (1): Section
1926.251(a)(4) requires that special custom design grabs, hooks, clamps or
other lifting accessories be proof-tested prior to use. A voluntary industry
consensus standard, ASME B30.20, states that load tests "should" be
performed. For purposes of OSHA compliance, does §1926.251(a)(4) supersede the
ASME requirement?
Answer
Yes. The OSHA requirements regarding proof-testing special custom design grabs,
hooks, clamps or other lifting accessories are governed by 29 CFR
1926.251(a)(4), not the ASME B30.20 standard. Section 1926.251(a)(4) states:
Special custom design grabs, hooks,
clamps, or other lifting accessories, for such units as modular panels,
prefabricated structures and similar materials... shall be
proof-tested prior to use to 125 percent of their rated load. [Emphasis added.]
Further, §1926.32
provides certain definitions which are used in the application of Part 1926
regulations. Specifically, §1926.32(q) states:
Shall means mandatory.
Therefore, the
requirement that special custom-design grabs, hooks, clamps or other lifting
accessories be proof-tested prior to use is mandatory, and failure to comply is
a violation of OSHA requirements.
Question (2): Other than for slings, it
appears that there are no inspection criteria for below-the-hook lifting
devices in the OSHA regulations. Would I be in compliance with OSHA
requirements if I followed ASME B30.20 for inspections of below-the-hook
lifting devices?
Answer
Yes. Section 1926.251 does not address inspection criteria for below-the-hook
lifting devices, except for slings used in conjunction with other material
handling equipment.
Under the "General Duty Clause" (Section 5(a)(1)) of the Occupational
Safety and Health Act, employers must:
furnish to each of [its] employees
employment... free from recognized hazards that are causing or are likely to
cause death or serious physical harm...
The construction
industry recognizes the necessity for inspections of below-the-hook lifting
devices. An employer who follows ASME B.30.20, specifically sections 20-1.3.1
through 20-1.3.7 and 20-1.3.9 with respect to inspections for below-the-hook
lifting devices (other than for slings), would be considered to be in
compliance with OSHA requirements.
Links
to other OSHA Letters on 1926.251
It’s to our benefit to know
that your equipment is safe and sound. I can appreciate the ease and
affordability of plastic lifting boxes. But they aren’t safe. They aren’t rated
for a crane lift. The common fork load capacity is rated at 1500 lbs. If that
were an engineered number, then the tote would be good for 500 lbs, or less as
a crane lifting item. I would say less because nothing is supporting under the
middle of the tote. And when will that plastic become brittle? Will it be
during a lift like this one where it’s asked to bend? Let’s not meet the loved
ones of a co worker after choosing to insert weak links into our lifting plans.
Out with the plastic. Demand ASME designed and rated products at the minimum. Stop flying these items and hoping they hold together
while you choke them with slings. And that’s all you are doing… Hoping.
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