What inspectors found March 16

Damage was so severe in three areas that had officials been aware, Metro would immediately have stopped running trains through them. Those cables were repaired during the system shutdown.

The areas indicate where inspection teams found some or all of the following conditions: damaged cables, damaged cable connecting boots, debris encroaching on electrical areas and water infiltration. Below, a look at one of the damaged jumper cables near Foggy Bottom station.

Four years of incidents on Metrorail

There were 216 total smoke and fire incidents on Metrorail in 2015, more than double the total for 2014.

Monday’s problem: Damaged cables

Wiedefeld said Monday’s fire occurred in a “jumper cable.” These cables work like extension cords to bridge gaps in the third rail in areas such as emergency exits. If a jumper cable is damaged, particularly if its insulation is compromised, electric current can flow out of the cable in the wrong place and cause smoke or fire. On Wednesday, crews inspected Metro’s roughly 600 jumper cables on all six lines.

Previous problem: Loose electricity

The National Transportation Safety Board said the smoke in the L’Enfant Plaza incident was caused by electrical arcing, which occurs when electricity escapes its prescribed path. Arcing problems have bedeviled Metro, particularly in areas that have water leaks.

Another issue: Bad connectors

Federal safety officials investigating the L’Enfant Plaza incident warned that some power-cable connector assemblies are poorly constructed, lacking the proper kind of sealing sleeves. The problem can cause electricity to escape, generating heat and smoke.

The tragedy near L’Enfant Plaza

On Jan. 12, 2015, one woman died and at least 86 were sickened when a Yellow Line train was stuck in a smoke-filled tunnel south of the L’Enfant Plaza station for more than 35 minutes. Train operator James Curley repeatedly begged for permission to back up to the platform because passengers were screaming and choking. He was instead told to “stand by” while another train was evacuated and left empty at the platform.

3:05 p.m.

A smoke alarm went off at the site of an electrical malfunction on the third rail of the southbound tunnel. The electrical arcing, still fed by a power source to the south, filled the tunnel with toxic smoke.

3:09 p.m.

Smoke is first seen coming from the tunnel by cameras at the station.

3:15 p.m.

Curley encounters heavy smoke as he travels southbound from the L’Enfant Plaza station. He stops with the back of his train, No. 302, 386 feet from the station platform.

3:16 p.m.

The Metro control center activates ventilation fans north of the station to pull smoke out of the tunnel.

3:18 p.m.

A 911 caller reports smoke coming out of a tunnel at Ninth Street and Maine Avenue. First responders are sent there.

3:22 p.m.

Metro notifies the Office of Unified Communication of smoke at L’Enfant Plaza station.

3:23 p.m.

Train No. 510 stops at the platform and is immediately evacuated.

3:23 p.m.

Train No. 510 arrives at the L’Enfant station platform.

3:24 p.m.

Metro orders that fans south of the station operate to pull smoke out, negating the effect of the other fans and causing smoke to settle in the tunnel. One set of fans should have been set to push smoke toward the other.

4:27 p.m.

Firefighters report that hundreds of passengers have been evacuated. One passenger later died.

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