Best Ignition Interlock Device with 10 Top Picks

When I first started researching the requirements for keeping a vehicle safe and compliant, I realized that “ignition interlock device” means much more than just a mandatory breathalyzer. I’ve personally dug deep into various locking mechanisms, from the official compliance devices required after a DUI to essential mechanical safety switches in generators and machinery. Understanding the nuances of the best ignition interlock device is critical for both legal requirements and everyday home safety. This guide covers a wide range of top-rated interlock options designed for reliable performance.

IMAGE	PRODUCT NAME	AMAZON LINK
	Smart Start Ignitiion Interlock Mouthpiece	View on Amazon
	DICMIC Ignition Lock Cylinder Switch with Left Driver Side…	View on Amazon
	81910-M7110 Ignition Lock Switch Assembly with Keys Fit for…	View on Amazon
	Xdodnev CZ93-K1 Door Safety Interlock Switch Actuating Key…	View on Amazon
	QYZZRS Generator Interlock Kit Compatible with Eaton Cutler…	View on Amazon
	Dorman 924-784 Mechanical Key Relearn Ignition Lock…	View on Amazon
	Roundup 7000400 Interlock Switch KIT	View on Amazon
	Generator Interlock Kit for Square D QO or Homeline 150…	View on Amazon
	Interlock Switch Fit for Lazer Z 934026 AYP 539101080…	View on Amazon
	Eaton LS-S11-ZB Safety Key Interlock Switch, Key Actuator…	View on Amazon

Smart Start Ignitiion Interlock Mouthpiece

If you are dealing with mandatory state compliance, hygiene and convenience are paramount when using a breathalyzer device daily. The Smart Start Interlock Mouthpiece is designed specifically to ensure your experience with your mandated device is clean and straightforward. It’s a small, essential accessory that fits easily into your routine and your pocket, providing peace of mind every time you use your vehicle. Having a dedicated, easy-to-clean mouthpiece drastically improves the user experience for compliance programs.

Key features that stand out:
– Easy to use and clean: Simple design allows for quick rinsing or wiping.
– Convenient to carry or store in your car: Minimal bulk ensures discreet storage.
– Designed to fit your LifeSafer vehicle interlock device: Ensures perfect compatibility and reliable sampling.

Pros:
– Essential for maintaining hygiene during repeated use.
– Very cost-effective accessory.
– Highly portable.

Cons:
– This is an accessory, not the interlock device itself, requiring the primary unit.

Best for: Drivers currently enrolled in a mandatory Ignition Interlock Program (IIP) needing replacement or spare hygienic mouthpieces.

Expert Opinion: While seemingly minor, the quality and fit of the mouthpiece are crucial for accurate breath sample submission. This official accessory ensures calibration integrity and reduces potential errors associated with ill-fitting generic parts.

DICMIC Ignition Lock Cylinder Switch with Left Driver Side Door Lock Cylinder Compatible with 2011-2015 Kia Optima 2013-2017 Kia Rio Replace# 81900-1WK00, 81970-2TA00

For those needing reliable automotive repair, this DICMIC replacement kit provides everything required to restore your vehicle’s key function. When the internal mechanical interlocks within your ignition cylinder fail, you can face frustrating issues like keys getting stuck or the inability to start the car. This comprehensive kit includes both the ignition lock cylinder switch and the door lock cylinder, ensuring consistency across your vehicle’s locking system. It’s a high-quality, standardized manufactured component designed for longevity.

Key features that stand out:
– [REPLACE PART NUMBER] 81900-1WK00, 81970-2TA00: Direct fitment replacement simplifies the repair process.
– [FITMENT MODEL] Compatible with 2011-2015 Kia Optima, compatible with 2013-2017 Kia Rio: Excellent application specificity.
– [PACKAGE INCLUDE] 1x ignition lock cylinder switch, 1x left driver side door lock cylinder, 2x key: Provides a complete matching set.

Pros:
– Complete kit simplifies installation and guarantees key compatibility between the door and ignition.
– Uses high-quality materials for durability.
– Cost-effective OEM alternative.

Cons:
– Installation can be complex and may require professional auto technician assistance.

Best for: Kia Optima and Rio owners needing to replace a worn or damaged mechanical ignition lock cylinder.

Expert Opinion: Ignition lock cylinders are mechanical interlock systems that prevent unauthorized starting. When replacing critical security components, using a matched set like this is highly recommended to prevent key mismatch issues and ensure the vehicle’s immobilizer system remains functional.

81910-M7110 Ignition Lock Switch Assembly with Keys Fit for Kia Forte 2019-2021, Soul 2020-2022, Seltos 2021-2024 – Ignition Lock Cylinder with Housing – Replace# 81900-M7E00, 81910M7110, 81900-M7D00

This assembly is a robust, full replacement for modern Kia vehicles that use a traditional physical key system. When an ignition interlock cylinder fails, it often means the entire housing needs replacement due to complex locking pins or electrical switch issues. This kit is built using durable ABS plastic and strong metal components, ensuring it stands up to repeated, high-stress use. It provides a reliable mechanical interlock that keeps your vehicle secure.

Key features that stand out:
– [Vehicle Fitment]: Compatible with Kia Soul, Seltos, and Forte (2019-2024 range): Wide range of application.
– [Replace Part Number]: Multiple compatible OEM numbers: Excellent cross-reference ensures correct selection.
– [Durable Material]: Features durable ABS plastic and strong metal components: Built for long-term impact resistance.

Pros:
– Complete housing and cylinder assembly simplifies repair.
– Durable construction promises longevity.
– Includes two new keys.

Cons:
– Recoding the key to the vehicle’s immobilizer chip may be necessary after installation.

Best for: Kia owners experiencing failure of the physical ignition lock mechanism or housing.

Expert Opinion: Modern ignition systems incorporate sophisticated anti-theft interlocks. Replacing the entire assembly ensures all internal electrical contacts and mechanical locking components are refreshed, providing the most reliable fix for starting issues related to cylinder wear.

Xdodnev CZ93-K1 Door Safety Interlock Switch Actuating Key Silver Tone Direct Acting

Moving into the industrial safety sector, the Xdodnev CZ93-K1 is a key component in machine safety systems. This direct-acting safety interlock switch ensures that machinery doors or covers remain closed and secure while the machine is operational. Its purpose is to physically interrupt power if the safety perimeter is breached, preventing injury. The focus here is on rapid, reliable operation under harsh industrial conditions.

Key features that stand out:
– Operating speed: 0.1m~0.5m/s: Fast reaction time for safety critical applications.
– Rated insulation voltage(UI): 400V: High electrical safety rating.
– Vibration shock: mechanical: Approx.100G’S: Extremely robust build quality.

Pros:
– High vibration and shock resistance.
– Reliable operation in high-frequency use environments.
– Excellent insulation for electrical safety.

Cons:
– Requires integration into a larger control circuit and isn’t a standalone safety product.

Best for: Industrial automation, machinery guards, and control panels requiring mandatory safety cut-off mechanisms.

Expert Opinion: In industrial environments, safety interlocks are non-negotiable. This product’s high shock rating suggests it’s suitable for heavy-duty applications where mechanical reliability is crucial for operator protection.

QYZZRS Generator Interlock Kit Compatible with Eaton Cutler Hammer 100 Amp and 125 Amp Panels Breaker,for Safe Usage of Portable Power During Outage,Professional and Interlock Kit (1)

This is perhaps the most essential form of home electrical safety interlock. A generator interlock kit is a manual transfer switch device that physically prevents the main utility breaker and the generator breaker from being ON at the same time. This is critical for preventing “backfeeding,” which sends dangerous voltage back onto the utility lines and risks electrocuting utility workers. This QYZZRS kit is designed specifically for Eaton Cutler Hammer panels, offering robust safety during power outages.

Key features that stand out:
– Compatible with Eaton Cutler Hammer 100 Amp and 125 Amp Panels Breaker: Specific compatibility ensures a safe fit.
– Safe use: Prevents utility and generator supplies from being ON at the same time: Core safety function.
– Includes detailed installation instructions and labels: Simplifies the DIY installation process.

Pros:
– Mandatory safety feature for connecting a portable generator to a home panel.
– Prevents dangerous and illegal backfeeding.
– Comprehensive package with all necessary hardware and labels.

Cons:
– Only compatible with specific Eaton Cutler Hammer panels, limiting application.

Best for: Homeowners needing to safely connect a portable generator to their electrical panel via a mechanical interlock.

Expert Opinion: Using the best ignition interlock device (in this case, electrical interlock) for generator systems is vital. This type of interlock is often preferred over external transfer switches due to its lower cost and simplicity, provided the panel compatibility matches perfectly.

Dorman 924-784 Mechanical Key Relearn Ignition Lock Cylinder Compatible with Select Models (OE FIX)

Dorman is well-known for providing smarter repair solutions, and this ignition lock cylinder is a prime example. For many older Chrysler, Dodge, and Jeep vehicles, replacing the ignition cylinder traditionally required time-consuming manual recoding or a trip to the dealer. This Dorman OE FIX cylinder includes an exclusive tool that allows you to code the new cylinder to your existing key simply by inserting and turning the key. This functionality saves significant time and hassle during replacement.

Key features that stand out:
– Smarter solution – this replacement ignition lock cylinder includes an exclusive tool that codes the new cylinder to your existing key: Unique self-coding functionality.
– Saves time – avoids manual recoding, reducing install time by as much as an hour: Major benefit for DIYers and mechanics.
– Incredibly simple – insert key, turn clockwise/counter-clockwise, and remove to code: Highly user-friendly process.

Pros:
– Dramatically simplifies the key programming process.
– High-quality replacement part.
– OE FIX ensures proper fitment.

Cons:
– While simple, the coding tool is specific and must be used correctly for the system to interlock properly.

Best for: Chrysler, Dodge, Jeep, and Plymouth owners seeking a quick, hassle-free replacement ignition lock cylinder that self-programs to the old key.

Expert Opinion: The ability to recode the cylinder without specialized electronic tools represents a significant practical advantage. This mechanical interlock solution addresses a common, frustrating issue with older vehicle repairs.

Roundup 7000400 Interlock Switch KIT

The Roundup 7000400 Interlock Switch KIT is a genuine OEM replacement part designed for specific commercial kitchen equipment, such as high-speed vertical contact toasters and food steamers. In commercial settings, interlocks are essential for both safety and preventing equipment damage. This switch ensures that components are correctly aligned or secured before the machine powers on, protecting both the operator and the expensive appliance. Using a genuine OEM part guarantees compatibility and maintains regulatory compliance for commercial food preparation machinery.

Key features that stand out:
– Genuine OEM replacement part: Ensures perfect fit and reliable performance.
– AJ Attunes – Roundup parts support their line of high-speed vertical contact toasters, food steamers, hot dog grills and food warmers: Specific focus on commercial food equipment.
– Use genuine OEM parts for safety reliability and performance: Emphasis on quality and safety standards.

Pros:
– Guaranteed compatibility with Roundup commercial equipment.
– Ensures the machine operates within safety parameters.
– Built for the high demands of commercial kitchen use.

Cons:
– Highly specialized use limits applicability outside of commercial kitchens.

Best for: Restaurants and food service providers needing to maintain or repair Roundup brand commercial kitchen equipment.

Expert Opinion: In high-speed commercial operations, failure of safety interlocks can lead to serious injury or catastrophic equipment failure. Sticking to genuine OEM replacement switches is the best path for minimizing downtime and maintaining safety certifications.

Generator Interlock Kit for Square D QO or Homeline 150 or 200 amp Panel – Generator Lockout Kit, Interlock Switch – 1 3/8″ Spacing Between Main and Generator Breaker

Similar to the QYZZRS kit, this Generator Interlock Kit serves the crucial function of a mechanical interlock to prevent backfeeding power. However, this model is designed specifically for Square D QO or Homeline panels, which are very common in residential installations. Constructed from premium materials like Alloy Aluminum and Inox 304 Screws, this lockout kit resists bending and warping, ensuring that the interlock mechanism remains reliable under stressful conditions.

Key features that stand out:
– PREMIUM MATERIALS – M35 Cobalt Drill Bit, Inox 304 Screws and Nuts, and high-quality Alloy Aluminum: Focus on longevity and resilience.
– COMPATIBLE DESIGN – Compatible with the Square D QO or Homeline 150 or 200 amp panels: Excellent fit for popular residential panels.
– ENHANCED SAFETY – Prevents backfeeding with a mechanical interlock: Core safety function protecting utility workers.

Pros:
– High-quality, durable materials.
– Budget-friendly solution compared to full transfer switches.
– Includes necessary installation tools (Cobalt Drill Bit).

Cons:
– Requires extremely precise installation to function correctly.

Best for: Homeowners with Square D panels who need a durable, reliable generator lockout device for safe power transfer.

Expert Opinion: This type of mechanical interlock is indispensable for home generator safety. The focus on high-quality materials ensures the device maintains its structural integrity over time, which is essential for a product whose failure could be life-threatening.

Interlock Switch Fit for Lazer Z 934026 AYP 539101080 Ariens 934026 2248H High Sierra Toro 13AP60RP744 Oregon 33-028 Scag 481545 Power Units & HydrDrives 52″ 60″ and 72″, 2 Pack

This product is a critical safety interlock for lawn and garden equipment. Mowers require safety switches (often called “kill switches” or “interlock switches”) to ensure the blades or engine stop immediately if the operator leaves the seat or if safety guards are missing. This universal switch offers strong multi-brand compatibility, fitting over 30 well-known brands. Its primary function is the Automatic Stop Function, eliminating the risk of misstarting and ensuring safe operation for both commercial landscapers and home users.

Key features that stand out:
– Interlock Switch Strong Multi-Brand Compatibility: Fits extensive list of popular mower brands.
– Automatic Stop Function: Stops the mower immediately when unsafe conditions are detected: Essential operator safety feature.
– Reduce Maintenance Costs: Prevents misoperation, reducing equipment damage: Practical financial benefit.

Pros:
– Extremely wide application range.
– Comes in a convenient 2-pack for spares or multiple machines.
– Significantly improves operator safety and liability protection.

Cons:
– The electrical connectors may require modification depending on the specific mower model.

Best for: Landscaping professionals and homeowners replacing safety interlock switches on riding mowers or zero-turn vehicles.

Expert Opinion: Safety interlocks on mowers are constantly exposed to moisture, vibration, and debris. This multi-compatible replacement provides the reliable electrical connection needed to enforce safety rules—a non-negotiable feature for power equipment.

Eaton LS-S11-ZB Safety Key Interlock Switch, Key Actuator Type, DPST-1NO/1NC Contacts

The Eaton LS-S11-ZB is a high-end, dedicated safety position switch for industrial machinery requiring secure monitoring and emergency shut-off capabilities. This key interlock switch requires a physical key to change its status, ensuring that access to potentially hazardous areas is strictly controlled. Featuring 1NO and 1NC contacts with positive opening, it is designed to meet stringent UL and international safety certifications, making it ideal for use in safety devices for emergency shut-off functions.

Key features that stand out:
– Safety interlock switch for safety position switch used for monitoring electric signals in safety devices for emergency shut-off: High-level industrial safety focus.
– 1NO and 1NC with positive opening: Ensures reliable contact separation even if contacts weld together.
– UL Recognized for safety and CSA, CE, and CCC certified: Extensive international quality assurance.

Pros:
– Extremely high safety certification level.
– Positive opening feature is critical for industrial standards.
– Robust construction and secure key activation.

Cons:
– Premium pricing due to specialized industrial safety rating.

Best for: Industrial manufacturers, engineers, and plant operators implementing or upgrading high-reliability machine guarding and emergency stop systems.

Expert Opinion: When dealing with hazardous machinery, relying on standard switches is insufficient. Eaton’s key interlock, with its positive opening contacts, is one of the best ignition interlock device options for high-risk industrial applications where personnel safety is the paramount concern.

Practical Buying Advice: Choosing the Right Interlock

Choosing the right device depends entirely on your application:

• For DUI Compliance (Breathalyzer): You are primarily concerned with the device’s reliability and ease of use, focusing on accessories like the Smart Start Mouthpiece. Always confirm the device itself is state-certified and correctly calibrated.
• For Vehicle Repair (Ignition Cylinder): Look for kits that offer OE Fix compatibility and simplified key coding (like Dorman) to save labor time. The interlock here is mechanical—it prevents unauthorized starting.
• For Home Power Safety (Generator): Specific panel compatibility is non-negotiable. Ensure the generator interlock kit (Square D, Eaton Cutler Hammer) is rated for your exact breaker panel size to prevent catastrophic failure or fire.
• For Machinery Safety (Industrial/Mower): Reliability and high environmental resistance are key. Ensure the safety switch has the required automatic stop functionality and high voltage insulation. Industrial models should feature positive opening contacts.

Final Verdict: Which Interlock is Best?

Determining the single best ignition interlock device is impossible because the applications are so diverse, ranging from court-ordered devices to critical home safety components.

If your need is related to legal compliance: The most important choice is selecting a certified IID provider (like Smart Start, whose accessory we reviewed). For accessories, the Smart Start Ignitiion Interlock Mouthpiece provides the necessary hygiene and compatibility for daily mandated use.

If your priority is Home Safety: The clear winners are the generator lockout kits. The Generator Interlock Kit for Square D QO or Homeline panels stands out due to its premium materials and specific compatibility with widely used residential electrical systems, making it a reliable safety investment.

If your focus is on Automotive Reliability: The Dorman 924-784 Mechanical Key Relearn Ignition Lock Cylinder offers the most practical benefit, eliminating complex programming hassles and significantly reducing repair time compared to traditional replacement methods.

Best Ignition Interlock Device FAQ

What exactly is an ignition interlock device (IID) and how does it relate to safety switches?

While the term “ignition interlock device” often refers to the mandated breathalyzer required after a DUI, the principle of an interlock is any mechanism—mechanical or electronic—that prevents one action from occurring until a prerequisite condition is met. In cars, the breathalyzer interlock prevents starting until a clean breath sample is provided. In generators, the interlock prevents the main breaker and generator breaker from being simultaneously active.

Are generator interlock kits legal to install myself?

Generator interlock kits (like the Square D or Eaton compatible ones) are mechanical devices designed for safety and are often legal to install yourself. However, local codes and homeowner association rules may vary. It is highly recommended to have the final installation inspected by a licensed electrician to ensure proper function and adherence to all generator safety regulations.

How often do mandatory ignition interlock devices need calibration?

Mandatory IIDs typically require periodic calibration checks, often called “roll-overs” or “monitoring appointments,” mandated by state law. These checks usually occur every 30 to 90 days. During this time, the provider checks the device’s accuracy and downloads any usage logs for compliance monitoring.

What is “backfeeding” and why is a mechanical interlock necessary to prevent it?

Backfeeding is the dangerous process of sending electrical power from a residential generator back into the public utility grid. This poses a severe risk of electrocution for utility line workers who believe the line is dead. A mechanical interlock (generator lockout kit) physically prevents the utility breaker and the generator breaker from being in the “on” position at the same time, making backfeeding impossible and ensuring compliance with home power safety standards.

Why are OEM parts recommended for automotive ignition lock replacement?

When replacing an ignition lock cylinder, using OEM (Original Equipment Manufacturer) or high-quality OE FIX components ensures that the cylinder’s internal mechanism and electrical connections are engineered to the exact standards of the vehicle. This reliability is vital because the cylinder is a key component of the vehicle’s anti-theft system and must interlock perfectly with the steering column and immobilizer system.

Can the best ignition interlock device for DUI compliance be tricked or bypassed?

No. Modern, state-certified IIDs use highly sophisticated breathalyzer technology and anti-circumvention features, including cameras, rolling re-tests, and tamper seals. Any attempt to bypass or tamper with the device is immediately logged, often resulting in a violation report sent directly to the monitoring authority, potentially extending the mandatory installation period.