Leak down Rates

D.O.T. Standard Allowable Leakdown

Department of Transportation (D.O.T.) standard for allowable leakdown in air systems is as follows:

1. 4 P.S.I. drop in the front air system in a 2 minute time period.
2. 4 P.S.I. drop in the rear air system in a 2 minute time period.

This translates into 120 P.S.I. drop in a one hour time period. In other words, both needles would be allowed to go to zero P.S.I. in one hour. All control valves, relay valves, check valves, etc. have allowable leak rates, even for new components. It is not within the scope of Foretravel, Inc., or any manufacturer, to completely eliminate air leaks. This is why D.O.T. sets the standard for allowable leakdown rules in the interest of safety. However, Foretravel, Inc.'s leakdown rate is set as follows:

Foretravel, Inc. Allowable Leakdown

1. 6 P.S.I. in the front air system in a one hour time period.
2. 6 P.S.I. in the rear air system in a one hour time period.

This translates into an approximate 60 P.S.I., allowable leakdown rate, for each air system, in an overnight park mode (10 hours). This is an extremely small air leak. The Foretravel, Inc. standard is 20 times more stringent than the D.O.T. required safety standards, which allow 120 P.S.I. per hour.