Navigating the complexities of government regulations can be overwhelming and difficult at times. This is a first of a 3 parts series about DOT air brake fitting regulations and what it takes to be compliant with the government regulations.

Unlike standard passenger vehicles, tractors and trailers employ the use of air brakes due to the inherent reliability and durability over time. Within the air brake system, the fitting is an integral connection point between tractor compressor and the rest of the air brake components. In an effort to improve overall road safety, the National Highway Traffic Safety Administration (NHTSA) (which is part of the Department of Transportation, or DOT) implemented regulations aimed at ensuring the safety and reliability of air brake systems and, subsequently, air brake fittings. The regulations cover aspects such as corrosion, labeling, temperature resistance, minimum bend radius, air leakage and more. Fittings that meet these requirements are marked with the letters “DOT”, along with the manufacturer’s name and size. – Hence “DOT” fittings.

Complying with these regulations are so important because commercial trucks and trailers use compressed air to energize their service and emergency brakes. There is an air compressor that is attached to the truck engine, this brings the system up to pressure. The air gets to back to the trailer brake valves through airlines that are connected with DOT fittings. If the fittings leak, no air will get to the braking components and the tractor or trailer subsequently won’t be able to brake. Conditions under a tractor trailer are pretty harsh and it makes it that much more important to have trouble free operation of the DOT air brake fitting under all conditions. Failure of these systems mean that the tractor trailers driving on the roads with everyone, including our families, cannot stop under standard or extreme conditions.

When you buying a DOT air brake fitting, this means that the manufacturer of the fittings should be continuously conducting extensive testing to confirm that these requirements are being met to ensure that their products are indeed compliant and, more importantly, will ensure that the brakes work when they need to. The interesting thing is that this compliance is essentially on the honor system, there is no 3rd party confirmation that manufacturers are meeting the appropriate standard – so it is really important to know who makes your DOT fittings, and that they are a reputable manufacturer that you can trust to do the right thing. It is also important to note that the requirements are tough to meet – we have invested millions of dollars into the latest manufacturing technologies in order to ensure the precision and repeatability that is necessary to produce millions of fittings that work right every time.

When reputable fittings manufacturers, like Alkon, apply the DOT label, customers can rest assured that the DOT air brake fittings have been subjected to extensive and ongoing testing to make sure the requirements have been met. Over the past several years, we have noticed an increase in DOT air brake fittings being sold in the U.S. that are manufactured overseas by small companies that have attempted to copy the designs of reputable manufacturers. Knowing how critical even the most minor features are to full compliance, I find this trend very concerning. All these companies have to do is register with NHTSA and properly mark the fitting to sell into the US market. Some even fall short of jumping this initial hurdle.

The one thing we would like small OEMs, Distributors and Fleets to walk away with – I would not want those imported fittings on the big rig behind my family on the highway when I have to hit the brakes.

Just because you have purchased them from a US company does not mean they are manufactured by a reputable company. It is so critical that you know who made your DOT air brake fittings and that they are someone you can trust.