Engineering certification for our cattle guards
Powder River had McNeil Engineering in Sandy, Utah analyze every guard model we sell. The letter is dated September 18, 2026 and stamped by Anthony B. Schmid, S.E., a licensed structural engineer in Utah. Every model passed for its rating.
Download the stamped letter (PDF, 11 pages)
What it certifies
| Rating | Max axle load | Certified for | Powder River parts |
|---|---|---|---|
| H-15 | 12 tons (24,000 lb) | H-15 | 036-15708 to 036-15814 |
| H-20 | 16 tons (32,000 lb) | H-20 and HS-20 | 036-20708 to 036-20814 |
| U-54 | 25 tons (50,000 lb) | U-54, HS-25 and HL-93 | 036-54808 to 036-54814 |
| U-80 | 30 tons (60,000 lb) | U-80 | 036-80808 to 036-80814 |
Every length (8', 10', 12', 14') in both road lengths is listed by part number in the letter.
How they were checked
The engineer ran the guards through the AASHTO LRFD Bridge Design Specifications, the same rulebook state transportation departments use for bridges, and found them adequate for the AISC 360 steel requirements as well. The loads carry a 33% allowance for impact and a 1.35 live-load factor. Both the rails and the main beams were checked: C8x11.5 channel under the H-15 and H-20 guards, heavier C10x15.3 under the U-54 and U-80, all A-36 steel. Tandem axles four feet apart were checked too.
If you're buying for a county road or a state job, the line most specs care about is on page 2: the guards "are adequate for their respective design loads," and the U-54 models "are also adequate for HS-25 and HL-93 design loads."
Certification questions
Can I get the stamped letter for a county or DOT submittal?
Yes. Download it from this page. It's the full 11-page letter with the engineer's stamp, signature and calculations. If your reviewer wants something specific to your job, call us and we'll ask Powder River.
Which guard meets HL-93?
The letter certifies the U-54 models for HS-25 and HL-93 design loads. The H-20 models are certified for H-20 and HS-20, the rating most county roads ask for.
Does the letter cover the foundation?
No. It covers the guard itself: the rails and the main channels. The foundation under it depends on your soil and site, so a county road job may still need its own foundation design. Our precast bases and free foundation drawings are a starting point.
Does it cover both road lengths?
Yes. The engineer analyzed a maximum span of 8 feet, which covers both the 7'5" and 8' road lengths.
Pick your rating
Shop cattle guards or read what each rating means.