Carbon Monoxide Accumulation in Subway Car Kills Rider

This case involves a woman who died while riding the subway system in a major American city. The subway had been stopped inside of a tunnel due to mechanical issues further down the line. Unbeknownst to the riders, the tunnel contained a large amount of carbon monoxide, which continued to accumulate as the train sat stationary in the tunnel. After several minutes had passed, a number of riders began to fall ill, reporting feelings of lightheadedness and confusion. One of the riders subsequently died from carbon monoxide poisoning. It was alleged that the ventilation system in the subway tunnel was inadequately designed to remove harmful gasses from the subway tunnels.

Question(s) For Expert Witness

1. Do you have experience designing, manufacturing, or inspecting ventilation systems for subway cars or other mass transportation systems?

2. Can you explain how these systems are intended to function in events similar to the one described above?

3. Do you believe the woman's death may have been preventable had the ventilation system been designed and/or operated differently?

Expert Witness Response E-008214

I can explain how the emergency ventilation system for a subway is intended to operate in the case of smoke and fire events, as well as with the accumulation of harmful gasses generally. I have worked on several including a case where a woman who died from carbon monoxide poisoning, and several cases where animals died due to ventilation failure and failure of emergency ventilation systems. I thoroughly understand ventilated air systems, tunnel ventilation fans, indoor air distribution, and the clearance of pollutants from confined spaces using ventilation air exchange. I have advised graduate students on CFD modeling of large interior air spaces. Furthermore, I serve on a committee who writes and approves emergency ventilation standards.