Appendix E - Air System
Foretravel Owners Manual
Page E-1
Rev. 06-02
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 al-
lowable 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.