Undesired Emergency Application Entering a Tunnel
You are the engineer on a 9,000-foot intermodal train, 6,200 tons, two units, traveling at 40 mph. The head end enters a 2-mile tunnel, and 20 seconds later the train goes into emergency. The train stops with the rear 1,500 feet outside the tunnel. Brake pipe pressure is 0 psi and will not recharge; you hear a heavy air leak from the rear. Radio communication with the rear is poor inside the tunnel. The conductor is in the cab with you. It is dark, temperature 30°F, and the tunnel has a narrow walkway and no lighting. The dispatcher is on the radio asking for status. You have a flashlight and a portable radio; the rear DPU is not equipped.
1. What are your immediate actions in the first five minutes?
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First, secure the train: apply hand brakes on enough cars to hold the train, especially if the grade is unknown, and do not rely on the emergency application because brake pipe pressure is at zero and leaking. Protect the rear and flanks per rule, and notify the dispatcher immediately with your location, train length, and that you have an emergency application with a heavy leak. Because you are in a tunnel, check for fire, smoke, and derailment before walking; use flashlights and portable radios, and keep the conductor with you or in a safe agreed location. Do not attempt to release the brakes or recharge until the cause is found. If there is any sign of fire or hazardous release, evacuate upwind and request emergency response.
2. How do you inspect and determine the cause, given the rear is outside the tunnel?
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Start at the rear, since the rear 1,500 feet is outside the tunnel and the leak is described as heavy. Inspect the rear car and the last several cars for a burst hose, broken pipe, open angle cock, or a derailed car that has torn the brake pipe. Work forward methodically, using the portable radio to stay in contact with the dispatcher. If the leak is at a hose gasket or coupling, repair or replace it; if a car is derailed, stop and protect. Do not open angle cocks or make a temporary repair that bypasses a safety device without rule authority. Document the car number and defect.
3. What conditions must be met before releasing the brakes and moving?
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Before releasing, the cause must be corrected, the brake pipe recharged, and a leakage test performed. Confirm that all hand brakes are released, that the train is intact and on the rails, and that the rear pressure is within the required gradient. Notify the dispatcher and obtain permission to proceed. If the train cannot be recharged or the leak cannot be repaired, the dispatcher must arrange for a relief crew or mechanical help; do not move with a known brake pipe leak. After release, make a brake application and observe that the brakes set and release before trusting the train on the grade or in the tunnel.