Why Air Brakes May Be Responsible for Semi-Truck Accidents

Key Points:

• Air brakes are different from the brakes you’d find on typical passenger cars because they use compressed air instead of fluid to apply brake pressure to stop a semi-truck.
• All commercial motor vehicle drivers must complete a daily report at the end of each driving workday to confirm all truck parts and equipment are in working order.
• Some reasons why air brakes fail include improper alignment or installation, maintenance failures, manufacturer defects, outside factors, truck overloading, or driver error.
• It is important to have an experienced truck and car accident lawyer on your side that understands how to properly investigate truck accidents, especially ones that involve potential brake issues

Table of Contents

Stopping an 80,000-Pound Commercial Truck

When we think of brakes, we think of the fairly standard technology found on most passenger vehicles. The brakes in most cars use brake fluid to move components and apply brake pressure to stop the vehicle.

However, the brake systems required to stop an 80,000-pound commercial semi-truck operate differently from regular passenger brakes. Because of the greater potential harm a semi-truck accident can cause, they typically have more advanced, heavy-duty braking systems.

What Are the Different Styles of Brakes in Commercial Trucks?

There are two main types of brakes used in commercial trucking: drum brakes and air brakes.

Drum brakes are typically cheaper to make and maintain. These brakes use fluid to create a series of events that causes friction to make a vehicle come to a stop. While drum brakes have good braking power, continual use on a heavy vehicle may cause overheating, which can lead to brake fade. When brake fade occurs, it can impact stopping ability and result in increased stopping time.

Air brakes use compressed air instead of fluid to apply brake pressure. While not required, air brakes are known as the best way to safely stop heavy commercial trucks. This is due to the ability to put intense pressure on the brakes without the brakes locking up.

Air brakes allow for a shorter stopping distance and have nearly double the lifespan of comparable drum brakes. One major safety advantage of air brakes is the fact that no brake fluid is used. This also eliminates the potential for fluid to leak and cause brake failure.

This system is not perfect, however. Brake failure is still a factor in almost 30% of semi-truck accidents, making it the leading reason for collisions. If you are involved in an accident with a semi-truck, make sure you find out what type of braking system the truck was equipped with.

How Air Brakes Operate

It is critical that all parts within the air brake system are in good and operable shape, or brake failure may occur.

Air brakes are made up of the following parts:

• Air compressor (single or dual piston)
• Dryer
• Governor
• Storage tanks
• Foot valve
• Primary and secondary circuits
• ABS valve
• Rear ABS valve
• Quick-release valve

Here’s how air brakes work:

First, the compressor draws in and compresses air. Then, the air is sent through the dryer, which removes any moisture in the air. The air is then moved to onboard storage tanks, which hold the compressed air until needed.

The governor regulates the amount of air pressure that the air compressor builds. Once the air compressor has reached 120 PSI, the governor will bypass the compressor, so no more air is pumped.

When a commercial truck driver presses on the brakes, the air is sent through the primary and secondary circuits to apply brake pressure to the front and back wheels. Onboard valves are there to release any excess air pressure. Each time the brakes are used, the air brake system will repeat the process to restore compressed air for braking.

Laws That Help Prevent Brake Failure on Semi-Trucks

There are several federal laws in place that set guidelines and requirements on semi-trucks and their drivers.

All commercial motor vehicle drivers must complete daily reports at the end of each driving workday. This task requires the driver to inspect several parts and accessories on their semi-truck, including:

• Brakes
• Tires
• Lights
• Horn
• Windshield wipers
• Wheels

If there are any deficiencies or problems with these or other systems on the semi-truck, then these must be identified in a daily report and signed by the driver. If there are two drivers, only one is required to sign the report, as long as both drivers agree on the report’s contents.

Air brakes, just like any brakes, will wear out over time and eventually fail if not properly inspected and serviced. Brakes should always be replaced before they reach a failing point. This is why daily inspections are so crucial to maintaining the safety of semi-trucks.

What Causes Air Brakes to Fail?

There are many reasons why air brakes may fail on a semi-truck. Some of the most common causes include:

• Improper brake alignment
• Condensation
• Worn-out components
• Bad driving
• Overloaded truck
• Water in the air tank
• Oil in the air tank
• Air compressor failures

It is difficult to know what caused an air brake failure without the appropriate investigation and accident analysis. It is important to determine whether an accident was caused by an equipment failure, human error, or both. Once you establish what caused an air brake failure, you will be in a better position to decide what legal options you may have.

How Negligence Is Determined When Brake Failure Is the Cause of a Semi-Truck Accident

Each truck is designed with a specific braking system that should be used and maintained properly. When brakes fail to operate correctly, it is important to determine if an individual or company’s negligence was the cause.

While brake failure may be due to a manufacturer’s faulty product, infrequent and improper safety maintenance checks are more commonly to blame.

It is also important to determine the actions of the truck driver during the accident. To determine negligence, you will need to inspect whether the truck driver’s actions caused the brakes to lock up or fail.

Other Factors That Can Result in Brake Failure Accidents with Semi-Trucks

Many other factors can lead to brake failures on semi-trucks. For instance, if a semi-truck is overloaded and too heavy, then that can be a prime reason for a brake failure.

Another factor that may contribute to brake failure is the experience level of the driver. Inexperienced drivers may not be familiar with properly operating air brakes, which function differently from drum brakes and brakes found on regular vehicles. If a driver improperly uses their front brakes or does not adequately navigate going up and down hills, then brakes can fail, leading to serious accidents. Of course, these are just a few examples, as there are many causes for brake failure.

How Bad Brakes on Semi-Trucks Can Result in a Legal Claim

Trucking companies are required by law to inspect and maintain the brakes on their commercial vehicles. As a result, trucking companies and/or their insurance companies can be held liable for accidents that cause injuries or property damages due to bad brakes.

It is important to have a legal team on your side that understands how to properly investigate truck accidents, especially ones that may involve potential brake issues.

Consultations Are Free at The Millar Law Firm

It is best to speak to an experienced personal injury attorney to determine the answers to these and any other questions you may have about your semi-truck accident case. Call The Millar Law Firm today at (770) 400-0000 or contact us online to set up a free consultation with one of our attorneys.