The Swedish Transport Administration divides the country's roads into five different classes, depending on how much traffic passes by the road.
Class 1
When it has fallen 1 centimeter of snow, the plow truck has two hours to plow the route. After it has stopped snowing, the road should be snow- and ice-free within two hours. Anti-slip is normally treated with salt.
Class 2
When snow has reached 1 centimeter, the plow truck usually has three hours to plow the route. After it has stopped snowing, the road should be snow- and ice-free within three hours. Anti-slip is normally treated with salt.
Class 3
When snow has reached 1 centimeter, the plow truck usually has four hours to plow the route. Four hours after the end of the snowfall, there must be at least snow- and ice-free wheel tracks on the road. Snow strings can thus occur. Anti-slip is normally treated with salt.
Class 4
When snow has reached 2 centimeters, the plow truck usually has five hours to plow the route. Five hours after the end of the snowfall, no more than 2 centimeters of snow may lie on the road. Non-slip is normally treated with sand.
Class 5
When snow has reached 3 centimeters, the plow truck usually has six hours to plow the route. Six hours after the end of the snowfall, no more than 3 centimeters of snow may lie on the road. Non-slip is normally treated with sand.
Source: Swedish Transport Administration
See SVT's reporter explaining why roads are classified differently in the clip.
Here you can see what class your route has: