Ignition Interlock

The Washington State Patrol is the regulatory authority of ignition interlock devices, interlock service technicians and interlock service centers throughout Washington State. The ignition interlock program of the Washington State Patrol is operated out of the Forensic Laboratory Service Bureau’s Impaired Driving Section and consists of law enforcement officers and support staff dedicated to interlock compliance and public safety.

A breath alcohol ignition interlock device (BAIID or simply IID) is attached to the ignition of a motor vehicle and is designed to prevent a motor vehicle from being operated by a person who has consumed an alcoholic beverage. When properly installed and calibrated, the IID will prevent a driver from starting a motor vehicle if the device detects a breath alcohol concentration (BrAC) above the prescribed setpoint.

Ignition Interlock Clients

Ignition Interlock Manufacturers 

  • Interlock Manufacturers

    Each ignition interlock manufacturer below has one or more approved interlock device models certified in the state of Washington. Please Note: The Washington State Patrol does not endorse any manufacturer, service center, or device. Their appearance on this page confirms only that the devices have been certified by the Washington State Patrol and meet federal and state rules for breath alcohol ignition interlock devices.

    1A Smart Start, LLC
    500 E Dallas Road – Grapevine, TX 76051

    Draeger Inc.
    1221 S Belt Line Rd., Suite 700 – Coppell, TX 75019

    Guardian Interlock Systems
    4290 Glendale Milford Rd., Cincinnati, OH 45242

    11035 Aurora Avenue – Des Moines, IA 50322

    4290 Glendale Milford Rd. – Cincinnati, OH 45242

    Simple Interlock LLC
    4320 Osage Beach Pkwy, Suite 218 – Osage Beach, MO 65065

    Information about device certification and standards is available by writing to the Ignition Interlock Program, Washington State Patrol, 811 E. Roanoke, Seattle WA 98102.

  • Interlock Technicians

    Interlock Technician Application
    • Interlock Program WAC & RCW Technician Booklet
    Technician Exam Instructions and Answer Sheet
    Interlock Technician Declaration

    All applicants for Washington State certified ignition interlock technician AND those seeking re-certification must complete an examination administered by the Impaired Driving Section of the Washington State Patrol [WAC 204-50-046 (2)(ii)]. The applicant must score eighty percent or higher on the knowledge and skills examination to be eligible for a letter of certification. Applicants should complete, and successfully pass, the knowledge and skills examination prior to submitting their application for approval.

    Procedure for Completing the Washington State Patrol Ignition Interlock Knowledge and Skills Examination:

    • Thoroughly review the laws governing ignition interlocks contained in the Revised Code of Washington (RCW) chapter 43.43.395 and chapters 46.20.710 through 46.20.755.
    • Thoroughly review all chapters of Washington Administrative Code (WAC) 204-50 addressing ignition interlock rules and regulations.
    • Successfully complete all ignition interlock manufacturer, device, service center and technician training as provided by the supporting
    • Contact the Washington State Patrol Ignition Interlock Program to request a copy of the examination using one of the following methods:

    Phone (206) 720-3018
    Fax (206) 720-3246

    Write to:
    Washington State Patrol
    Ignition Interlock Program
    811 E. Roanoke St.
    Seattle, WA 98102

    When completed, return only the answer sheet to one of the contact methods outlined above.

    The applicant will be contacted by the Washington State Patrol within five business days (excluding state holidays) of receiving the answer sheet and provided the results of their examination

  • Service Centers

  • Devices/Manufacturers


  • Will the ignition interlock device shut off my vehicle's engine or stop my vehicle at any time?

    No. WAC 204-50-110 – Ignition interlock devices are designed to prevent the vehicle from being started. Once a vehicle is started any failed random retest or missed random retest will be reported as a violation and the vehicle’s horn will activate continuously but it will not shut off the vehicle.

  • I have an ignition interlock device requirement but my interlock equipped vehicle is temporarily disabled. May I drive a friend's vehicle or drive a rental/loaner car without an interlock until my vehicle is fixed?

    No. RCW 46.20.740 (2) – It is a criminal offense for a person with an ignition interlock restriction to operate a motor vehicle that is not equipped with an ignition interlock. Additionally, be sure to have the automotive repair or service facility complete a Washington State Patrol Vehicle Service Affidavit after the repairs are complete so that any incidents recorded on your device during this period are accounted for.

  • What happens if my ignition interlock equipped vehicle stalls while I am on the freeway temporarily parked on railroad tracks or in some other dangerous area?

    WAC 204-50-110 – Ignition interlock devices in Washington State are required to have a two minute “stall protection” safety window that allows for the vehicle to be turned back on without providing a breath sample within that time frame.

  • In extreme weather can I start my vehicle and let it run unattended until it warms up or cools down?

    No. WAC 204-50-110 – After the initial breath test is requested to start the vehicle, random retests are requested at various times while the vehicle is running. If you leave a vehicle unattended while running you may miss one of these random retests which will be counted as a violation and likely activate your vehicle’s horn.

  • Someone I know is driving a vehicle without an interlock or having their friend/child/spouse blow into the interlock device while they drive. Who do I contact about this?

    RCW 46.20.750 – If you have information that a person required to have an ignition interlock device is driving a vehicle without one or circumventing the interlock by having someone else provide a breath sample, we would like to investigate that. Please contact our office at (206) 720-3018 and we will notify the trooper responsible for that region. Providing as much information as possible, such as the driver’s name, date of birth, address, vehicle license number, etc. will be very helpful to our investigators.

  • What government mandated fees are included in my ignition interlock lease and what do they pay for?

    RCW 46.20.745 – The Washington State Department of Licensing (DOL) charges a $20 fee per person, per month from the ignition interlock company which is deposited in the ignition interlock device revolving account. This fee offsets DOL’s expenses for tracking installed interlocks and is used to supplement the costs associated with the indigent interlock account for those who have been approved based on financial limitations. For those approved under the indigent program this fee is waived. The Washington State Patrol charges a $10 fee per device for installation and a $10 fee bi-monthly per device ($5/monthly) which is appropriated to perform interlock certifications, monitoring, circumvention/tampering investigations, and interlock industry regulatory services. All other fees associated with the lease of an interlock device are at the discretion of the interlock manufacturer.

  • What does it mean that my interlock restriction is tolled day-for-day?

    RCW 46.20.720 (5) – Interlock restriction periods are calculated on a day-for-day basis. This means that when a driver has an interlock restriction for one year they must have an interlock installed for at least 365 days. Any removal of a interlock device during the period of restriction will extend the restriction for each day without an interlock.

  • What are the final requirements I must meet to have my interlock device removed (commonly known as Compliance Based Review) and what types of incidents/violations will extend my interlock restriction period?

    RCW 46.20.720 – Compliance Based Review (or CBR for short) refers to the final period of your interlock restriction. Prior to having your interlock restriction lifted your interlock manufacturer will review of your interlock device history for any qualifying violations which may extend your restriction period. Your interlock manufacturer must certify to the satisfaction of DOL that none of the following incidents occurred prior to your scheduled restriction end date:

    1. Any attempt to start the vehicle with a breath alcohol concentration of 0.04 or more unless a subsequent test performed within ten minutes registers a breath alcohol concentration lower than 0.04 and the digital image confirms the same person provided both samples;
    2. Failure to take any random test unless a review of the digital image confirms that the vehicle was not occupied by the driver at the time of the missed test;
    3. Failure to pass any random retest with a breath alcohol concentration of 0.025 or lower unless a subsequent test performed within ten minutes registers a breath alcohol concentration lower than 0.025, and the digital image confirms the same person provided both samples; or
    4. Failure of the person to appear at the ignition interlock device vendor when required for maintenance, repair, calibration, monitoring, inspection, or replacement of the device.

    If any of these incidents appear in your device history during your CBR period your interlock restriction will be extended. This may continue indefinitely until you have completed your CBR period without any violations.

    • For those who were arrested prior to July 23, 2017 your CBR period is 4 months.
    • For those who were arrested on or after July 23, 2017 your CBR period is 180 days.

  • What happens if I live (or move) out of Washington State but the Washington State Department of Licensing requires me to have an ignition interlock device?

    RCW 46.20.720 (8) – State licensing and law enforcement agencies have reciprocity agreements that allow for restrictions in one state to be enforced in others. This also applies to ignition interlocks. If you are required to have an ignition interlock device installed by a Washington State government entity, all other states will also require an interlock. Also, if you have an active interlock restriction in another state you will be required to have an interlock in Washington.

  • I have a medical problem that prevents me from providing a sample into an interlock. Can I have the breath threshold requirement reduced?

    No. WAC 204-50-110 (1) (c) – Washington State requires an interlock device to have a minimum threshold of 1500 ml (or 1.5 L) of breath for an acceptable breath sample. Clients who are experiencing difficulty meeting this minimum standard should contact their vendor for tips on providing a breath sample. Alternatively, clients may also contact the jurisdiction requiring the interlock device or the Department of Licensing to determine if they qualify for any authorized alternatives to an interlock.

  • Does Washington State allow remote lock out codes for ignition interlocks?

    No. WAC 204-50-090 – Washington State does not allow remove lock out codes for any ignition interlock device. Clients who have experienced a lock out must contact their device manufacturer to schedule an appointment to have the device serviced. Generally, this consists of having the vehicle towed into the service center or having an authorized mobile interlock device technician respond to the location of the vehicle.