Add your variables to the calculator - you will need to supply all the variables before being able to calculate whether or not a dilemma zone exists. If you need some hints or want to try to calculate yourself, check our info button to the help page at any time.
If a dilemma zone exists, the output will show you the distance from the traffic light stop line and the size of the dilemma zone.
The other possibility is that an option zone exists, this will be displayed as a distance from the traffic light stop line and the size of the option zone will also be given.