An IRS suspension is in place for 12 months, however you are typically eligible to install the interlock device to your vehicle and start driving 90 days after the offence. There are steps required to re-acquire the legal right to operate a motor vehicle and you should receive advice on those before doing so. IRS suspensions must be appealed within seven days of being issued, so it is imperative that you receive advice from a lawyer quickly to preserve your rights.