Initial Terminal Brake Test in Cold Weather
At 04:10 on a -8°F morning, engineer M. Chen completes a Class I initial terminal brake test on a 105-car mixed freight. The train has two AC locomotives and a brake pipe charged to 90 psi. During the leakage test, the brake pipe leaks 6 psi per minute. The dispatcher needs the train out of the yard before 04:30 to protect a junction. Chen's conductor says the leakage 'will tighten up once the train stretches and warms.' The yardmaster tells Chen to depart and note the leakage on the delay report. Chen has 1 hour 10 minutes left on his 12-hour clock. The train will descend a 1.1% grade for 6 miles within the first 20 miles. No repair track is available at the next terminal for 70 miles. What should Chen do?
1. May Chen depart with a brake pipe leakage of 6 psi per minute?
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Chen should not depart. The Class I initial terminal brake test requires brake pipe leakage not to exceed 5 psi per minute; 6 psi/min fails the test. Cold weather can affect leakage, but that is a reason to inspect and repair, not to depart with a known failure. The conductor's 'warms up' theory is not a valid retest, and the dispatcher's schedule pressure has no bearing on the brake test standard. The 1.1% descending grade makes the defect more serious: leakage reduces brake pipe pressure and can cause an undesired release or weak brake application on the rear of a 105-car train, where brake cylinder pressure and propagation are already challenged.
2. What must Chen do before the train moves?
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Chen should request a carman or repair track, have the leakage source corrected, and perform a new Class I test with leakage at or below 5 psi per minute. He should document the initial result, the repair, and the retest, and notify the dispatcher that the train is not available. If no repair is possible, the train should not move. He should not accept a delay report as a substitute for the required test, and he should not allow the train to be moved to the next terminal for repair unless the movement is authorized under the railroad's special instructions for a defective brake system.
3. How should Chen handle the conductor and yardmaster pressure?
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He should state the specific test result and the rule limit, not argue about whether the train will 'warm up.' He can say: 'Leakage is 6 psi per minute; the Class I test limit is 5. I cannot depart until it is repaired and retested.' He should ask the yardmaster to arrange repair or release him from the assignment, and he should notify the dispatcher so the junction is protected by other means. If the yardmaster continues to pressure him, Chen should document the instruction and request that the refusal be entered in the record. Safety-related refusals are protected, and signing a release under pressure would weaken his position.