Free independent reference. Original examples, not official exam questions or a driving assessment. Follow current provincial rules, signs and authorized directions.
Headlights, night, winter and rural roads →Identify the equipment’s actual state
Ask whether the plow is moving or stopped and which warning lights are flashing. Do not memorize “snowplow equals 60” without those conditions. A lower applicable limit and the actual road conditions still need attention.
A plow’s working speed can be much lower than surrounding traffic. Seeing it late is a reason to reduce speed early, not to keep closing the gap while deciding what to do.
Source: SGI — Sharing the road: snow plows ↗The snow cloud can hide the reason to wait
SGI warns about the small blizzard created by a working plow. The obstruction is not just the machine: the cloud can hide its position, the surface ahead or other vehicles.
Stay back and be patient. SGI says plows pull over periodically to let traffic pass. That advice is not a guaranteed timetable or a reason to follow close enough to pressure the operator.
Source: SGI — Sharing the road: snow plows ↗Apply the distinction in three original cases
Original learning cases
A stopped plow has blue and amber lights flashing. This matches SGI’s stated 60 km/h passing condition; it is not the moving-plow case.
A working plow is travelling slowly inside a dense snow cloud. The absence of the particular stopped-plow restriction does not provide the missing visibility for a pass.
The operator pulls into a place where traffic can get by. Reassess the available view and traffic before proceeding rather than copying the car ahead.
Permission to pass is not proof of a safe gap
The moving-plow guidance does not mean “pass whenever the posted limit permits.” You still need a clear view and a manoeuvre that is safe for the lane, traffic and surface. If you cannot assess those conditions, wait.
Learn the contrast with the stopped-equipment rule below. This page focuses on snow-clearing visibility and the moving/stopped distinction; the linked emergency-vehicle reference covers other roadside assistance situations.
Source: SGI — Sharing the road: snow plows ↗