Atlanta’s Top Rated Boutique Injury Law Firm

Call Don Singleton
(770) 889-6010

Call Don Singleton
(770) 889-6010

What Is An Ignition Interlock Device?

Donald Singleton
May 13, 2022

The ignition interlock device, also known as a breathalyzer for vehicles, is a breathalyzer designed to prevent drivers from consuming alcohol after they start their motor vehicles. The driver must blow into the device’s mouthpiece to start or continue driving.

Learn more about ignition interlock devices meaning, how they work, how much they cost, and more with this guide. All your questions will be answered, and we’ll get you back on the road quickly.

What is an ignition interlock device?

History of Ignition Interlock Devices

When was the ignition interlock device invented? In 1969, Borg-Warner Corporation (now BorgWarner, Inc.) developed the first performance-based interlocks. Jeffrey Feit, an NJ student in 1981, won a statewide competition for innovations with his primitive breathalyzer-based interlock design.

He presented his prototype to the Young Scientist competition in Dublin in 1983 as a student in Limerick. Through the 1980s, alcohol sensors became commonplace in the marketplace. These sensors use semiconductor (nonspecific) technology. Semiconductor-type (Taguchi) interlocks were very durable and very effective. Still, they did not hold calibration very well, were susceptible to altitude variations, and did not react to non-alcohol sources.

The device has been delayed for more than a decade while systems to prevent circumvention improve. From the early 1990s onwards, the “second generation” fuel cell sensors began to appear on interlocks. Interlocks installed today must meet the standards of the National Highway Traffic Safety Administration (NHTSA).

What is an ignition interlock device (IID)?

For use in cars, IIDs are portable breathalyzers that prevent users from starting their cars after they have consumed alcohol. They’re called breathalyzers for cars or breath alcohol ignition interlock devices (BAIIDs). They’re small and look like a TV remote control.

A typical IID consists of these components:

  • Handheld Unit
  • Mouthpiece
  • Relay Cord
  • Camera Unit.

How do I use an ignition interlock device?

Tests for breath alcohol content, or BrAC, are typically conducted using one of the following methods:

  1. Blow-Inhale-Blow – works by the driver blowing into the car breathalyzer mouthpiece for a few seconds without removing their mouth, inhaling back in, and blowing again into it. Users will find this to be the most accurate test, and it is the easiest to use.
  2. Straight Blow requires you to blow extremely hard to get an accurate sample, is difficult for users, and is less accurate than other devices.
  3. Blow And Hum – Having to blow into the mouthpiece is a difficult skill to master, resulting in many customers being locked out.

Despite their similar shapes, some ignition interlock devices are easier to use than others. Since drivers don’t have to read the device, it makes it easier to perform random retests since there is only one button to activate.

A failed sample may prevent you from starting the device, but the device cannot shut down your car once it is running. An ignition interlock device cannot turn your vehicle off once it has been started.

How does an ignition interlock work?

A driver blows into the mouthpiece of the car breathalyzer to provide a breath sample once the device is installed. Devices that test for breath alcohol content (BrAC) within legal limits are available. The driver can start the car with the keys in the ignition if the blood alcohol level is under the limit (usually .02).

This prevents an intoxicated driver from starting the car

In order to prevent drunk drivers from starting their cars, DUI interlock devices are installed in vehicles. If your breath sample is negative, your car won’t start.

Failures with breath samples are handled differently by each state. There is no retest limit in all states, but some have a waiting period after taking a new breath sample. Multiple failed attempts will lock you out after reaching that limit. In some states, you are allowed to submit samples until one passes.

Staying sober while driving

You will have to continue providing breath samples during your trip even after your vehicle has been started.

The alcohol interlock system is easy and safe to retest while driving in many situations since it features a one-button design and uncomplicated breath pattern. Drivers above the limit cannot start their cars if they submit a retest, preventing others from providing the sample.

A car breathalyzer will force you to pull over and stop your car if your BrAC is above the limit when you re-test. Each state has its own rules for retests. Your horn may honk, or your lights may flash until you turn off the car in some states. Once running, the device will be unable to shut down your car. Once your vehicle is started, it cannot be turned off by an ignition interlock device.

How long do I need an ignition interlock device?

Each state has its own ignition interlock law that determines when the device is required, for how long it is required, the type of device needed, and which monitoring authority is responsible for overseeing the device (probation officer, court, DMV, DOT, etc.) and other details.

Your license will be reinstated after you successfully complete the ignition interlock requirement. You may need to contact your DOT for an eligibility date for some states, while others require you to receive approval from your monitoring authority. If you need help understanding what your state requires for removing the device, you can contact our customer support.

In Georgia for 12 months. The device must remain installed for 12 months after a four-month suspension of their licenses, during which they will not be able to drive at all. After the device has been installed, a limited license can be applied for. Just remember that Georgia has a zero-tolerance law which we already discussed in our legal resources section.

License Revocation, Fines, and Jail in Georgia Ignition Interlock DUI Laws

  • For first offenses (misdemeanors): A jail sentence of 10 days to 12 months, fines of $300 to $1,000, license suspension of up to one year, and no less than 40 hours of community service. Participating in an alcohol risk reduction program is mandatory. You might be evaluated and treated for alcoholism or attend an alcohol treatment program.
  • For second offenses (misdemeanors): Upon license restoration, it is mandatory to install an interlock device for one year after that, fines up to $1,210, 18-month suspension of license, community service, probation for 12 months, and a fine of 3 days to 1 year in jail. A DUI alcohol or drug use risk reduction program must be completed after 30 days of community service. The DUI defendant may be required to attend a substance abuse treatment program.
  • For third offenses – A Misdemeanor of High and Aggravated Violation (Habitual Violator): Fines up to $5,210, jail time of up to 120 days, suspension of the license for five years, installation of an ignition interlock device for six months, completion of a DUI Alcohol Risk Reduction Program, and receiving a psychological evaluation. The Department of Motor Vehicle Safety will seize your license plate as a Habitual Violator.
  • For fourth and subsequent offenses – Determination of habitual violator (Felony): If you are convicted of DUI alcohol or drug use, your driver’s license will be suspended for 5 years, you will have to complete a DUI Alcohol or Drug Use Risk Reduction Program, and the device will need to be installed on your vehicle for at least 1 year after your license is restored. Vehicle forfeiture is possible. A person is placed on probation for 5 years (minus any time he or she has spent behind bars).

Administrative License Revocation (ALR) Procedures

Georgia is one of 41 states having ALR, which means that if you blow over .08 or refuse to take a BAC test, your license will be confiscated immediately. Even though you have not been convicted in a criminal trial, your license will be suspended or revoked at that point. You can be charged with an administrative license suspension despite not being charged with a drunk driving offense. Besides the traditional DUI judicial punishments like license suspension, jail time, community service hours, ignition interlock devices, and alcohol and drug rehab, this was intended to be a separate and additional measurement.

An officer at the scene will issue you with temporary limited driving privileges for a period of 10 days. If you want to challenge this case, you can request a hearing during that time. A court administrator will examine the case. After thirty days, you can request a work permit for the first-time offender, but if you don’t request a hearing, your license will be automatically suspended for one year on the 11th. You will need to install an ignition interlock device after the suspension period is over.

It is important to remember the differences between judicial and administrative cases. This can have a significant impact when it comes to judicial procedures, but you must act quickly if you want to fight it.

You can check how many points can you get on your driver’s license in Georgia if you are curious easily

Judicial Procedures

When a person has a blood alcohol concentration (BAC) of .08% or higher, he or she is not allowed to drive. For any driver with a BAC of .08% or higher for a second offense, the court must order the installation and monitoring of an interlock device.

Ignition Interlock Device FAQs

Can I unplug my interlock device?

You can easily connect your head unit to your curly cord and then simply bring it inside without the curly cord in nearly all states. Afterward, you can re-connect your head unit the next time you drive, and it will be ready to accept your initial breath test immediately before you begin driving.

How do you pass the ignition interlock after drinking?

What is the answer to the question, “How do I pass the interlock when I’m drinking?” The plain answer is you can’t. If you cheat the interlock, you could lose your place in the ignition interlock device program and, therefore, your privilege to drive. There’s no way to fool the system into thinking you weren’t drinking.

Is an interlock device required after the 1st offense in Georgia?

A person in Georgia is prohibited from driving if their blood alcohol content is more than . 08%. Any driver with a BAC of . 08% or higher for a second offense must have an interlock device installed and monitored by the court.

What do ignition interlock devices record?

With your ignition interlock, you can record the following information: your blood alcohol content (BAC). The data recorded by your interlock is probably the most crucial to determining whether you can drive your vehicle at all. Starting and stopping, and subsequent testing.

How does the ignition interlock device work?

Using an interlock device, you can determine the amount of alcohol needed to generate that electrical current based on the electrical current generated by your breath. The device turns the engine on if the BAC level is under the threshold of 0.02 BAC.

Does the ignition interlock device damage car?

If you’re wondering if an interlock device damages your car, then we’re here to tell you that it does not. Ignition interlock devices (IIDs) will not damage any motor vehicle, no matter how old or new it may be.

Does the ignition interlock device have GPS?

Are interlock devices equipped with GPS? Definitely. Installing an ignition interlock device with GPS functionality may be required by your state. In the event that you are with restricted driving privileges in only certain areas by your state, this information helps track your location with each sample.

When is an ignition interlock device required?

For violators with BACs over 0.20 at the time of arrest, ignition interlock installation is mandatory following the mandatory suspension period. The installation of an ignition interlock is required for anyone convicted of DUI within the last 10 years.

Can an ignition interlock device be installed on a motorcycle?

Motorcycles are not typically fitted with ignition interlock devices (IIDs). Because IIDs can be used in various vehicles, including trucks, SUVs, vans, and cars.

Can an ignition interlock device be required for the first conviction of DUI?

In the event a person is convicted of a first offense of drunk driving, the court may order that any vehicle the person owns or operates be fitted with an ignition interlock device and that the person cannot operate a motor vehicle until that vehicle is so installed.

Donald Singleton

Donald Singleton


A Georgia native, Don founded Singleton Law Firm in 1999 as a continuation of his lifetime commitment to serving his state and community. He has concentrated his trial practice to representing victims of serious injury and wrongful death arising out of trucking, car, bus and motorcycle accidents, premises liability and a wide variety of other causes.

Contact Us for Help Today

Get a Free Consultation