The Truckers’ Report flatbed Hall of Shame.

Something that’s not needed to worry about. It’s in the FMCSA guidance ushered to determine how much securement is required. If you meet the requirement of 50% of the cargo weight secured you’re good.


Performance Criteria
FMCSA has adopted new performance requirements concerning deceleration in the forward direction, and acceleration in the rearward and lateral directions, that cargo securement systems must withstand. Deceleration is the rate at which the speed of the vehicle decreases when the brakes are applied, and acceleration is the rate at which the speed of the vehicle increases in the lateral direction or sideways (while the vehicle is turning), or in the rearward direction (when the vehicle is being driven in reverse and makes contact with a loading dock). Acceleration and deceleration values are commonly reported as a proportion of the acceleration due to gravity (g). This acceleration is about 9.8 meters/second/second (32.2 feet/second/second), which means that the velocity of an object dropped from a high elevation increases by approximately 9.8 meters/second (32.2 feet/second) each second it falls. FMCSA requires that cargo securement systems be capable of withstanding the forces associated with following three deceleration/accelerations, applied separately:

1. 0.8 g deceleration in the forward direction;
2. 0.5 g acceleration in the rearward direction; and
3. 0.5 g acceleration in a lateral direction.

These values were chosen based on researchers' analysis of studies concerning commercial motor vehicle performance. The analysis indicated that the highest deceleration likely for an empty or lightly loaded vehicle with an antilock brake system, all brakes properly adjusted, and warmed to provide optimal braking performance, is in the range of 0.8-0.85 g. However, a typical loaded vehicle would not be expected to achieve a deceleration greater than 0.6 g on a dry road. The typical lateral acceleration while driving in a curve or on a ramp at the posted advisory speed is in the range 0.05-0.17 g. Loaded vehicles with a high center of gravity roll over at a lateral acceleration above 0.35 g. Lightly loaded vehicles, or heavily loaded vehicles with a lower center of gravity, may withstand lateral acceleration forces greater than 0.5 g.
Generally, motor carriers are not required to conduct testing of cargo securement systems to determine compliance with the performance requirements. The new rules explicitly state that cargo immobilized or secured in accordance with the general securement rules, or the commodity-specific rules, are considered to meet the performance criteria.

 

Looks like someone at the FMCSA has way too much time on their hands.

 

Its the way I do my WLL math. It "sounds" different from the regs, from FMCSA...



To me, the way they word it is stupid. You have to reach ½ the weight of the cargo for WLL. A piece of securement that is direct tie down gets ½ its rated WLL, and an indirect securement gets its full WLL.

To me, it's a lot easier to just say direct is the stated WLL and indirect is double, add until the weight of the cargo is reached or exceeded. The amount of securement required works out the same, but is easier to figure for a dummy like me.

 

I don't want to sidetrack this too far, but:

While the manuals teach :

LoAdEd TrUcKs StOp BeTtEr!


Not that it's really any surprise that an outdated truism from the past survives in the CDL manuals. At least they actually used modern research numbers when they redid securement.

 

Which is why it dawned on me as I was replying to you, that you might be looking at it from that point of view. However, you were confusing THIS dummy with your description. . I always, as practicable, use Indirect securement to avail myself of the full value. I typically just automatically, in my mind, Halve the weight, and then count the required WLL's to meet it. Same as you do, from the opposite aspect, but I like a constant, and WLL is my constant, so I only have to reach my required tie down amount, but using the WLL up to that amount. Tomatoes, Tomuhtoes.

 

I'm not gonna lie. I'm usually wayyyy over secured. It just makes me feel better. Everytime I load my Monday load, I'm surrounded by guys who litterally throw half the securement I do. They are legal, but it just makes me cringe. It takes like another 5 min or so to throw a fee extra straps and it makes me feel better.

 

Oh no, I absolutely agree. Like that little video showed, 3 is the requirement, but personally, I'd have added 4th strap to that load in front of the dunnage just to add extra forward movement immobilization. My point of using the formula, though, is that I must at least reach the required. Then I usually look it over for where else I may want to put more securement, to 'fill in the gaps' I might find that make me feel better. I've had 3 loads that have given me trouble, but none of them came off the trailer. Shifted maybe because of softwood the shipper used. Tightening down enroute actually caused the failure of the softwood I advised them not to use, but I over secured the hell out of it, in case of the failure that occurred. Another time was the trailer tracked off road into a soft shoulder ditch. The load didn't move, but the trailer had to be winched out of it. If I can find them, I'll post them and you can see what I'm talking about, but yeah, over securment is the name of the game...I just need to make sure I always hit the minimum, and that's how I figure it, versus Pole Crusher's thought process.

 

Some stuff has very specific tie down requirements though, and the bare minimum is all you can do. I've had loads that each peace was 15' length, and two straps was all that could be thrown. Then you have equipment that has specific tie down points, which can be a pain to meet WLL sometimes.

In our securement class, we were shown an example of over securement. An AC unit that was crushed because the driver put a strap in the wrong place, because he thought there was no such thing as too much securement.

 

Not being sarcastic or looking to argue. Was I wrong in my opinion of the securement? Honest replies appreciated. Thanks.

 

If they were 4" straps indirect, that is legal for 27k lbs as long as it's 30' or less in length.