IID Calibration: What You Need to Know
Monthly calibration keeps your device accurate and downloads your data. Missing appointments can result in lockouts and violations.
30-60 days
Calibration Interval
15-30 min
Appointment Time
$0-50
Per Visit
What Is Calibration?
Calibration is a required monthly service appointment where a technician:
Recalibrates the sensor
Ensures accurate breath alcohol readings by adjusting for sensor drift
Downloads test data
All breath tests and events are transmitted to the monitoring authority
Inspects the device
Checks for tampering, damage, or malfunctions
Resets the countdown
Extends the time before the next required calibration
How Often Is Calibration Required?
Most states require calibration every 30 days, though some allow up to 60 days. Your device will warn you when calibration is due.
Typical Schedule
- • Every 30 days (most states)
- • Some states allow 60 days
- • Warning starts 7 days before due
- • Lockout if not completed on time
Grace Period
- • Usually 5-7 day grace period
- • Device gives countdown warnings
- • Don't wait until the last day
- • Schedule early in your window
What Happens at a Calibration
Arrive at service center
Drive to your scheduled appointment at an authorized location. Keep your vehicle running or leave keys with the technician.
Technician downloads data
All breath tests, violations, and events are downloaded from your device and transmitted to the monitoring authority.
Device is recalibrated
The breathalyzer sensor is adjusted using calibration gas to ensure accurate readings for the next period.
Test and confirm
You may provide a test breath sample to verify the device is working correctly. Receive confirmation and your next appointment date.
Calibration Costs
$0
Intoxalock, Smart Start
(Usually included)
$20-50
LifeSafer
(Often separate)
$50-100
Late/Missed Fee
(Varies by provider)
Many providers include calibration in your monthly fee. Always confirm what's included before signing up.
What Happens If You Miss Calibration
Device lockout
Your device will enter lockout mode, preventing you from starting your car. You'll need to have it towed to a service center or call for a mobile unlock.
Violation reported
A missed calibration is typically reported as a violation to your monitoring authority, which could affect your case.
Additional fees
Expect fees for the lockout reset ($50-100) plus any violation reporting fees. This can add up quickly.
Extended IID period
Depending on your state and the terms of your requirement, missed calibrations can extend how long you need the device.
Tips for Smooth Calibrations
Schedule early
Book your appointment a few days before the deadline in case you need to reschedule.
Set reminders
Use your phone calendar or the provider's app to get reminders before your due date.
Keep records
Save receipts and confirmations from each calibration in case of disputes.
Bring payment
If calibration isn't included, have payment ready. Some locations are cash-only.
Installation Guide
What happens during installation
IID Violations
Types and consequences
Sources
Calibration information based on provider guidelines and state requirements as of January 8, 2026.