Outside of large cities and towns, volunteer fire departments respond to most 911 calls. The volunteer firefighters use their own time and their own vehicles when responding to medical, fire, and car accident emergencies. They are the first line of defence in rural Ontario often arriving many minutes before police and ambulance. In rural areas where distances are large and fire halls are far apart minutes count, even more, when responding to a call.
In order to keep our selfless volunteers safe when responding to emergencies, the province of Ontario has allowed firefighters to display a flashing green light on or in their vehicles. These lights are restricted to the Ontario fire service.
These lights help other drivers to recognize that firefighters are en route to an emergency. Other drivers should be courteous and yield the right-of-way to these vehicles. Firefighters use the lights when they are either on their way to an emergency directly or en-route to the fire hall to dispatch in the fire trucks.
Insurance companies recognize the importance of these volunteers and support the use of green flashing lights. They warn drivers thought that misuse of the lights and aggressive driving tactics such as driving through red lights or stop signs without stopping or heading into oncoming traffic can result in the suspension of coverage.
If you are driving and see a vehicle following you or oncoming displaying a flashing green light you should slow down and yield the right-of-way to them. Pullover if safe, and allow them to pass. It is very frustrating for volunteers and dangerous for those in an emergency when they cannot respond quickly because of other drivers on the road.
Remember, please. Every minute matters in an emergency.
You can read more about the considerations made by the province and insurance companies here.