Cattle Guards aren’t effective for all animals!

Cattle guards are not effective for all animals

As we’ve stated in previous posts, cattle guards are not designed as a deterrent for all animals or even all livestock.  To illustrate the point, here’s a cute little Beagle on YouTube that summoned the courage to cross a guard on it’s own even thought the gap between the pipes presents a real challenge.

This neat little video shows how non-hoofed creatures can navigate their way across and this little guy who is still pretty young was able to find his way.

Cattle guard:  designed for most hoofed animals

Called by many names; cattle gaps, Texas gates and many more, they are specifically for cows, bulls and deer and some other hoofed animals.  The major exception that we don’t recommend them for are horses.  The equine animals have slender legs and smaller hoofs that can allow their legs to slip in-between the pipe and when their hoof hits the bottom of the vaulted area, it can expose their legs to breaking at it’s most vulnerable point on the leg.  A horse will most likely spook at the surprise of being in such a precarious situation and will probably struggle to get out.  This can lead to spooking it’s way to a broken leg which no one wants.  We recommend only gates for horses.

Goats, sheep and other smaller hoofed, sure-footed livestock are also able to cross the guards.  We also recommend traditional standard gates for these animals as well.

While they can be an effective barrier for all animals, they are designed for cattle and work best with this type of livestock.  Other animals are simply too sure footed, cleaver or have soft pads that allowing crossings without too much trouble.

If we can help answer and questions or provide any guidance for your particular project, please don’t hesitate to let us know.  We will be more than happy to help with small private plans or larger commercial or public roadway and government jobs.

Don’t forget Barn World has a large selection of products for all your livestock supplies including everything from hay feeders to grain bins.  Please contact us at (720) 23-2190 anytime!

 

 

 

Cattle Guards from Barn World

Cattle Guards

Barn World cattle guards allow easy access to farm and ranch land by eliminating the need for gates. Cattle guards give open access but keep livestock inside. All cattle guards are constructed with heavy wall steel pipe and extra thick steel channel. All ends of these cattle guards are capped to prevent rust. Wings and boxed cattle guards are available with all sizes.

Different Types of Cattle Guards

Boxed style cattle guards

cattle guards

Boxed styles are designed to lay directly on flat ground with a gravel under-layment recommended for drainage of these cattle guards. In many cases these boxed cattle guards are used for wheel washes in construction sites, dirt rattlers and for providing access to low or slow traffic sites such as cell phone towers, off-site construction, driveways and other low traffic areas.  In all cases a local contractor familiar with soil conditions and drainage considerations should be consulted when planning an installation.

Flat Style Cattle Guards

heavy duty cattle guard picture

The flat style is designed to be mounted on cement footings and is the most popular in high traffic areas such as public roadways.  They are bolted directly to the concrete footings that also create the ‘vault’ or empty space under the guard.  This provide a visual deterrent to animals and is very effective in dissuading and attempt at crossing.

The flat style is a permanent installation and some designs have a hinged area on the guard that allows the center section to be lifted for cleaning out debris that may have collected in the vaulted space area underneath.  This feature is not available on all guards, but may be included with most of the highway rated crossings.

General Cattle Guard Notes

Here are some general notes and guidelines:

Load Ratings

All cattle guards can withstand the weight of full tractor-trailer loads.  The non-rated are most popular for private property such as driveways and access for farm equipment.

The American Association of State Highway Transportation Officials (AASHTO) provides guidelines for cattle guards with maximum load ratings. AASHTO load ratings are suitable for all types of applications including heavy duty logging roads. (See the table at the bottom of this article for more details on AASHTO load ratings.)

AASHTO Design Specifications

    • H-15 (12 tons per axle)
    • H-20 (16 tons per axle)
    • U-54 (25 tons per axle)
    • U-80 (30 tons per axle)

Rated cattle guards will meet the specifications needed for state and federal requirements such as DOT, BLM, USFS, NP, and US Military installations. They are also used in commercial applications such as mining, forestry, agriculture, and petroleum production. Rated cattle guards are the product of choice for residential usage where city, county, or state regulations require the HS20 rating. Certified structural steel is used in the manufacture of HS20 rated cattle guards.

HS20 cattle guards will be certified by an independent engineering firm to meet commercial standards and are intended for government bids. For use on private land, buying standard cattle guards will save you thousands of dollars, are identical in size and are made out of the same materials. They just do not come with the certifications and paperwork all the way back to the steel mill that government agencies require. If a non-rated guard for a private drive is needed, use a standard cattle guard.

Cattle guards may be constructed with 3″, 3-1/2″ or 4″-1/2″ pipe.  The 4″ pipe allows for an approximate gap of 4″ between each pipe and be built with 9 pieces.  The 3-1/2″ outside diameter pipe guards have 11 pieces and are approximately 12-1/2″ tall.

There is no difference in strength between the boxed cattle guard and the flat styles of cattle guards.  These cattle guards are designed to accommodate full semi loads at 10 tons per axle.  All cattle guards weigh about 100 Lbs. per foot (a 10′ cattle guard weighs about 1,000 Lbs.). Add approximately 8 Lbs. per foot for boxed cattle guards and about another 200 Lbs. total for winged cattle guards.

Extending the depth of deterrant

To use for deer, you may need to place two cattle guards in tandem so you have 16 feet of protection. Cattle guards are easily bolted together to achieve greater distances in the direction of travel and create a larger deterrent for any animal wishing to attempt a jump.  Please note that we recommend standard gates be used when containing horses, goats, all small hoofed and sure-footed animals and animals with paws.

Ordering your cattle guard:

For a shipping quote, please send us an email with your destination zip code and quanitity or feel free to call the telephone number at the bottom of this page with any questions you may have about our cattle guards.

When ordering cattle guards you will pay for the order without the shipping and we will collect the exact shipping cost with a second charge to the credit card used for the order.
Note: You must have equipment available to unload the cattle guards from the delivery vehicle when it arrives. The delivery truck will require you to unload the cattle guard with a loader or fork lift or some other means upon delivery.

Note with regard to dimensions: Private use cattle guards are NOT built to exact dimensions. Sizes may vary slightly. Adding the removable box option will add about 7″ to the total length and width of the cattle guard. For example, a 12 foot cattle guard will be about 12′-7″.

If you have any questions, would like a quote with shipping or if we can help with anything at all, please don’t hesitate to contact us.  We’ll be glad to assist in anyway we can.

Don’t forget, Barn World is your headquarters for all your farm and ranch supplies including hay feeders, livestock scales, saddle pads and even grain bins.  We have a complete selection of livestock supplies for you everyday needs.

Cattle Guards add security and convenience to Livestock management

Barn World Cattle Guards offer livestock containment and peace of mind

Owning and running a ranch is a full time job.  It’s a 24 hour labor of love to raise and care for many animals at a time.  Moving around to feed and attend to your livestock requires access to pastures that must be able to contain and protect while allowing ease of access for equipment and vehicles.  A cattle guard is the perfect solution and they come in many different shapes and sizes to allow for most any type of use.

We do not recommend a cattle guard for all types of animals.

Horses and Small Hoofed Animals:

For some, they merely don’t work.  A goat or other small sure-footed hoofed creatures can trot right across the top of the rails, while for other hoofed animals, they provide a serious danger.  A horse, with it’s slender legs, can slide right down to the bottom of the vault where it exposes the weakest part of the leg to the steel rail.  With their instant flee from danger mindset, they can panic and struggle to get out and quickly break a leg.  We strongly recommend only using a gate to contain equine.
Deer are agile creates with small hoofs and we do see cattle guards work as an effective deterrent.  With their ability to jump large distances effortlessly, we typically install at least a 12 foot barrier, with 16 feet being an ideal distance to discourage them from jumping across.  To get that kind of depth, two guards are bolted together doubling the width of the ‘Texas Gate’ in the direction of vehicular travel.

Cattle Guards and Non-hoofed Animals

The working mechanism of this popular deterrent is that a hoof, when placed on a curved surface, does not allow an animal to properly balance it’s weight on the leg.  That, along with the limited depth perception in cows, provides a strong and seemingly impossible barrier to hoofed animals.  Those with padded feet have the ability to balance on the rounded pipe as their point of contact is flexible and allows for the transfer of weight onto a surface that can balance on the cattle guard.  As such, dogs, cats, coyotes and other ‘soft-footed’ four-legged friends can simply walk across.  A gate would be the best option to stop these guys.

 

Types of Cattle Guards

Barn World offers several types of cattle guards for private, commercial, public highway and heavy duty offroad equipment use. We comply with city, county, and/or state regulations.

Whether it’s called a Texas gate or a cattle guard, Barn World has the variety and selection needed to complete your project.

Private Use Cattle Guards

Private use cattle guards are perfect for farm and ranch use and for access areas where the total axle weight is up to 10 tons.  Semi trailers, tractors and large farming equipment are perfect for this type of guard.

Boxed style cattle guards

are designed to sit on flat ground. Gravel underlayment is recommended for drainage of these cattle guards. In many cases these boxed cattle guards are used for wheel washes in construction sites

.

Flat style cattle guards

designed to be mounted on cement footings

.

All cattle guards can withstand the weight of full tractor-trailer loads.
These cattle guards are constructed with an approximate gap of 4″ between each pipe.
Due to availability of pipe, cattle guards will be built with either 9 pieces of 4 1/2″ outside diameter pipe, or 11 pieces of 3 1/2″ outside diameter pipe and are 12-1/2″ tall.
There is no difference in strength between the boxed cattle guard and the flat styles of cattle guards.
These cattle guards are designed to accommodate full semi loads at 10 tons per axle.
Cattle guards weigh about 100 Lbs. per foot (a 10′ cattle guard weighs about 1,000 Lbs.). Add approximately 8 Lbs. per foot for boxed cattle guards and about another 200 Lbs. total for winged cattle guards.
To use for deer, you may need to place two cattle guards in tandem so you have 16 feet of protection. Cattle guards are easily bolted together and the extra depth will deter deer.
For a shipping quote, please send us an email with your destination zip code and quanitity or feel free to call the telephone number at the bottom of this page with any questions you may have about our cattle guards.
If you prefer, you may order your cattle guards online without the shipping total and we will forward the exact shipping cost for your review via email before processing your order.
A very important note: You must have equipment available to unload the cattle guards from the delivery vehicle when it arrives. The delivery truck will require you to unload the cattle guard with a loader or fork lift or some other means upon delivery.
Private use cattle guards are NOT built to exact dimensions and sizes may vary slightly.  Adding the removable box option will add about 7″ to the total length and width of the cattle guard. For example, a 12 foot cattle guard will be about 12′-7″.

Also see our unique ATV Cattle Guard:

For more information on cattle guards, installation or for help with any of your livestock supply needs, please visit www.BarnWorld.com today or call (720) 238-2190 and we’ll be happy to help.

Remember, Barn World is y our home for everything from saddle padshay feeders, grain bins, mineral feeders and everything to do with livestock.  We even carry livestock scales!

Cattle Guards can be dangerous to some animals.

Barn world
Buy Cattle Guards at Barn World

 

Cattle guards can be dangerous to some animals.

Although they may be the most efficient means of keeping livestock in without a gate, we don’t recommend them for all animals.

When Gates are the Best Option

Horses, may be be most at risk and when attempting to cross a guard.  The anatomy of a horses’ leg are such that they may slip down between the pipes forming the top of the guard and in to the vault area underneath.  This.will expose the weakest part of their legs to breakage, and once panicked, they can break it quite easily while struggling to get out. For their safety, we only recommend the use of gates with horses.

Goats and dogs are immune to cattle guards.   These sure-footed animals can simply walk with ease across the top of the pipes. Again, gates are the best option for containment.

Deer Guards

Deer are extremely athletic creatures.  Their ability to jump seems almost effortless as they cross large distances in graceful hops.  It becomes necessary to extend the distance of the guard in the direction of travel to deter these animals from attempting cross.  A common white tail or mule deer can easily jump an 8 foot distance without any effort at all.  These animals require a better deterrent than a cow and and by combining and bolting together two guards, the effective crossing area becomes too daunting even for these creatures.  We recommend at least 16 feet in the direction of the vehicle travel to dissuade even the most ambitious jumpers.

When considering barriers for deer, it is important to remember that not only can they jump across large distances, but they can also jump over tall fence lines.  This will require that the fence line be extended directly to the edge of the cattle guard.  With bovine, a set of wings prevent crossings on the shoulders of the roadway, but with deer, a tall fence right to the shoulder will required.  You want to prevent jumping across the ends of the fencing.

Cattle Guards are for Bovine

The best use for these barriers is of course with cattle.  The traditional round pipe guard has been found to be more effective than the flat top.  Flat top finishes allow for smoother vehicle crossings, but the best for livestock have rounded tops.

Part of the effectiveness is a visual trick played on the cattle’s depth perception.  The shadows created by the round pipe make the crossing look even daunting than it actually is.  This in turn creates an even larger mental barrier and dissuades most livestock from even considering a crossing.  There are the occasional large bulls that when properly motivated can attempt a 6 foot or sometimes even an 8 foot jump, but these are few and far between.  When properly installed with wings, almost all cattle will refrain from even attempting a crossing.

Although designed almost exclusively for cattle, these barriers may be also be used for deer, when properly installed.

ATV Cattle Guard

ATV Cattle Guard

New this year is the ATV guard.  Designed for ease of installation, this porable standalone is a great option for fence line crossings for off-road vehicles in remote areas.  We have even custom designed these for golf cart crossings of fence lines.  Simply make a cut in your fence and drop into place.  It couldn’t be easier to install and the built-in rise creates an extremely effective optical and physical barrier.

Barn World offers plenty of assistance

If you have any questions about your cattle guard project, or need any help at all, please don’t hesitate to contact Barn World when planning your installation.  We have a wide variety and can offer quotes and bids for any project.

Barn World, LLC
720.238.2190

 

 

Heavy Duty Cattle Guards, a Texas Fence from Barn World

Barn World Logo

Cattle Guards

Barn World offers several types of cattle guards for private, commercial, public highway and heavy duty offroad equipment use. We comply with city, county, and/or state regulations.

Whether it’s called a Texas gate or a cattle guard, Barn World has the variety and selection needed to complete your project.

Private Use Cattle Guards

Private use cattle guards are perfect for farm and ranch use and for access areas where the total axle weight is up to 10 tons.  Semi trailers, tractors and large farming equipment are perfect for this type of guard.

Boxed style cattle guards  are designed to sit on flat ground. Gravel underlayment is recommended for drainage of these cattle guards. In many cases these boxed cattle guards are used for wheel washes in construction sites.

Flat style cattle guards are designed to be mounted on cement footings.

 

All cattle guards can withstand the weight of full tractor-trailer loads.
These cattle guards are constructed with an approximate gap of 4″ between each pipe.
Due to availability of pipe, cattle guards will be built with either 9 pieces of 4 1/2″ outside diameter pipe, or 11 pieces of 3 1/2″ outside diameter pipe and are 12-1/2″ tall.
There is no difference in strength between the boxed cattle guard and the flat styles of cattle guards.
These cattle guards are designed to accommodate full semi loads at 10 tons per axle.
Cattle guards weigh about 100 Lbs. per foot (a 10′ cattle guard weighs about 1,000 Lbs.). Add approximately 8 Lbs. per foot for boxed cattle guards and about another 200 Lbs. total for winged cattle guards.
To use for deer, you may need to place two cattle guards in tandem so you have 16 feet of protection. Cattle guards are easily bolted together and the extra depth will deter deer.
For a shipping quote, please send us an email with your destination zip code and quanitity or feel free to call the telephone number at the bottom of this page with any questions you may have about our cattle guards.
If you prefer, you may order your cattle guards online without the shipping total and we will forward the exact shipping cost for your review via email before processing your order.
A very important note: You must have equipment available to unload the cattle guards from the delivery vehicle when it arrives. The delivery truck will require you to unload the cattle guard with a loader or fork lift or some other means upon delivery.
Private use cattle guards are NOT built to exact dimensions and sizes may vary slightly.  Adding the removable box option will add about 7″ to the total length and width of the cattle guard. For example, a 12 foot cattle guard will be about 12′-7″.

Also see our unique ATV Cattle Guard:

For more information on cattle guards, installation or for help with any of your livestock supply needs, please visit www.BarnWorld.com today or call (720) 238-2190 and we’ll be happy to help.

Remember, Barn World is y our home for everything from saddle pads, hay feeders, grain bins, mineral feeders and everything to do with livestock.  We even carry livestock scales!

Cattle Guard article from Working Ranch for Barn World

Love That New Cattleguard

– by Jennifer Showalter, Working RanchTV

cattle guard

Handling Equipment Powder River cattleguards are designed to meet the American Association of State Highway Transportation Officials (AASHTO) specifications. The strongest models are built to handle up to 30 tons per axle. Opening and closing a gate from time to time is no sweat off any rancher’s back. It’s when the same gate has to be gone through over and over that it becomes more trouble than it’s worth. With this in mind, every rancher has a cow or two that seems to be able to smell an open gate and won’t let anyone slide by without closing the gate each and every time. To ease the aggravation and time loss with these high usage areas, ranchers are relying more and more on cattleguards. Matt Johnson with Powder River Livestock Handling Equipment in Provo, UT points out, “Cattleguards are the ultimate gate replacement for high traffic areas, but placing a guard in an area that you access only occasionally or that is less critical for gate control is probably a waste of resources.” To help with the selection and installation of a cattleguard, Working Ranch went out and gathered some pointers from a few different manufacturers. This is what we found:

Picking the right one: When selecting a cattleguard there are a number of things to scratch the old noggin over. For starters, rancher must determine what is the heaviest and the widest pieces of equipment that will ever cross their cattleguard. They then have to look for the cattleguard that will meet those standards.

Quality materials and craftsmanship obviously influence the price of a cattleguard, but also determine its longevity as long as the proper load rating is not abused. “The higher the cattleguard (load) rating, the higher the cost. The U-rated guards that are designed for extremely heavy loads are the most expensive. Anytime the distance across a road exceeds 16’, shipping rates can rise dramatically. In terms of cost, it sometimes makes more sense to order two small cattleguards to bolt together in either direction than it does to order one large custom cattleguard,” says Robert Moore with Barn World, LLC in Parker, CO. Ranchers must decide if a flat or box type cattleguard works better in their environment and whether they prefer square or round rungs. Flat style cattleguards are placed over a dug out cement vault, whereas box style cattleguards basically have a built in vault and sit close to the top of the ground.

Placement: Cattleguard placement varies because of different soil conditions, climates, drainage, and intended uses. Barn World suggests ranchers have a local contractor, who is familiar with the area, set the more permanent types of cattleguards. Installation for these cattleguards typically involves digging a one foot deep trench that is one foot wider than the cattleguard. Six inch wide walls should then be poured around all four sides to prevent dirt from collapsing in. In the bottom of the trench, a 12” wide and 18” deep footer is needed under each beam of the cattleguard. It is critical that the cattleguard sits on footers that are sufficient to support the full load of traffic. Ranchers must keep in mind that the vault does not support a cattleguard in any way. While setting a cattleguard, installing large PVC pipe through the forms or digging out and adding gravel will help with drainage issues. Box cattleguards typically do not need a vault. Their box formation keeps dirt from working into the guard. “One of the biggest mistakes folks make is setting their (box style) cattleguard at ground level. You have to hold them slightly above grade and ramp up to and away from them to prevent them from filling in.

Cows don’t like to jump on a grade where their front-ends are higher than their back-ends,” explains Tom Jones, with JE Hill Precast in Leesburg, FL. When placing two cattleguards next to each other, both gaps and edges must be avoided. If there is a solid edge, cattle can master walking it. Some ranchers find it beneficial to purchase or build a set of wings for their cattleguard. “Various styles of wings can be used. They should be able to be secured to the guard grid or the base it is built on. Any type of wing should remove the risk that livestock can circumvent the guard,” notes Johnson. Jones points out another added benefit of wings, “Wings are a way of exaggerating the opening of a cattleguard. For example, if you have a 16’ cattleguard and a 16’ mower, you can lay the wings back and fit through.”

Limitations: Jones warns people that before they are sold on the idea of a cattleguard, they must be aware of their limitations. He finds that cattleguards typically do not work to separate cows from their calves or cycling cows from bulls. They also have a hard time holding cows without water from water and cows without feed from feed. Jones discourages ranchers from putting cattleguards in corners or along the edge of an alleyway where cattle can easily crowd them.

A peek at what these boys have to offer: Powder River: www.powderriver.com Powder River cattleguards are made out of structural steel, have square cross rails, and are either powder coated green or painted yellow. These cattleguards are designed to meet the American Association of State Highway Transportation Officials (AASHTO) specifications. Powder River builds a wide range of cattle guards with the strongest built to handle up to 30 tons per axle. Powder River cattleguards are available in 8’, 10’, 12’ and 14’ road lengths and 7’5’’ and 8’ widths. Powder River offers an optional three rail clean out section on all of their models except the U-80’s. Wings, steel posts, and pre-cast concrete bases are also available. Powder River stands behind its cattleguards with a five-year warranty.

Barn World: www.barnworld.com Barn World offers rated, standard, and basic boxed and flat style cattleguards.

cattle guards

Their rated cattleguards are intended for highways or for heavy off-road equipment. They are available with certified load ratings of H-15, H-20, U-54, and U-80. Barn World also offers an HS20 rated cattleguard to meet State and Federal requirements. Certified structural steel is used in the manufacture of all Barn World HS20 rated cattleguards. Barn World’s line of standard cattleguards are made with new .113 walled steel pipe, and like all Barn World cattleguards, come with a gray enamel finish. Their basic cattleguards are made of a heavy duty structural .188 walled pipe with diameters of 3.5” or 4.5”.

Barn World now offers a cattleguard design specifically for ATVs. These ATV cattleguards are made of 1.5 x 11 gauge square tubing and are 72” wide by 91” long. The overall width of these guards including their wings is 87”. A 14” ramp on each side allows them to be set on top of the ground and eliminates the need for a vault. Barn World is strictly an Internet-based business.

With three cattleguard manufacturing plants across the United States, Barn World strives to keep shipping costs at a minimum. JE Hill Precast: www.jehillprecast.com JE Hill Precast concrete cattleguards feature rounded top rails and built-in footers that eliminate the need to pour concrete. These cattle guards simply sit on top of the ground and are best positioned so they are held slightly above grade with a gravel ramp on both sides. They come in 12’, 14’, and 16’ road spans and all measure 6’6’’ across. JE Hill Precast’s standard cattleguards have a 72,000 pound gross vehicle weight (GVW) limit, while the heavy duty models have greater than a 90,000 pound GVW limit. These cattleguards weigh from 5,000 to 7,000 pounds depending on their size. JE Hill Precast cattleguards are designed so they require no additional construction, can be installed in two hours or less, and can easily be relocated.

Cattle Guard Post: HS20 Certified Cattle Guards from Barn World

BarnWorld.com
Barn World Has HS20 Certified Cattle Guards for Public Roads
Barn World makes superior HS20 rated cattle guards for public roads and highways. Our HS20 rated cattle guards are made from schedule 40 steel and come in a variety of sizes to fit various cattle guard projects.
We can alter the design of our cattle guards to use different kinds of pipe and rail depending on your needs. We have used round pipe, square rail, I-beam and other types of rail and channel to make rated cattle guards that are suitable for all public crossings.
Barn World HS20 rated cattle guards conform to AASHTO load rating requirement by type of truck and maximum axle load. Our rated cattle guards come with an engineer’s stamp and are certified to meet the AASHTO load ratings so you can feel confident that you are getting the best quality cattle guard. Call Barn World with your questions and plans to get quotes on HS20 rated cattle guards at 720-238-2190.
    

Cattle Guards for Public Roads require a Barn World HS20 Certified Cattle Guard

For superior HS20 certified cattle guards, visit www.BarnWorld.com.  We offer the necessary cattle guard certifications and strong cattle guards made from schedule 40 steel.  They come in a large variety of sizes to fit almost any project you may be involved in.

Used primarily for livestock control, they can offer a strong deterrent to deer if placed side-by-side to form 12′ or more barrier in the direction of travel and other animals as well.  Please note that we do not recommend cattle guards for horses, goats or dogs as they simply are not effective.  Horses can get a leg broken in them and goats, dogs and other sure footed animals will be able to cross the cattle guard.

Cattle guards can be made from different types of piping depending upon your livestock control needs.  We can use round 3-1/2″ or 4-1/2″  pipes or square pipes for the top rail.  Typically the larger and more round the pipe that is used on top, the more of a deterrent it is for livestock.  A 4-1/2″ pipe will have a greater curve and  thus provide a more unstable footing for a daring animal.  It will also have a larger gap between the pipes making it much more difficult to cross.  The smaller 3-1/2″ pipe will still keep livestock off of your cattle guard and will provide a smoother rider for crossing vehicles.  The same is true for the flat pipe.  It will offer a very smooth ride when crossing, but isn’t the strongest deterrent.

Every HS20 rated cattle guard is certified to conform to the load rating requirements provided by the American Asso