(a) You should avoid using maps to estimate between-stop distances under all circumstances.
(b) For services without designated stops, including demand response (DR and DT), jitney (JT), vanpool (VP), or fixed-route services without designated stops:
(1) If available, you should always use the onboard odometer to determine the between-stop distances for each service unit in your random sample. You should make sure that the vehicles for the sampled service unit have a working odometer onboard before they start for the sampled service unit.
(2) If your vehicle does not have an onboard odometer, you should determine the distance by retracing the path and the stops by automobile.
(3) You should record your odometer readings at least to one-tenth of a mile.
(c) For ferryboat (FB), aerial tramway (TR) and all rail services, you may want to predetermine the between-station distances for all routes and directions.
(d) For fixed-route services with designated stops, you should use one of two approaches:
(1) predetermine the between-stop distances for all routes and directions, or
(2) record the onboard odometer readings at individual stops.
(e) You may use different methods to predetermine the between-stop distances:
(1) use an up-to-date GIS of your network of routes and stops, or
(2) record the odometer readings while you drive through all of your routes and related deviations and directions.
(f) If you predetermine between-stop distances, you must keep them updated to reflect any changes in your services.