Toxic MBTA buses

This page documents the reports I’ve sent to the MBTA about buses with a strong diesel smell (i.e., toxic fumes) in their passenger compartments, a problem I’ve discussed in more detail here.

I haven’t reported anywhere near all the instances I’ve encountered of this problem. I stopped reporting them between July 2012 and January 2013 because it seemed it wasn’t doing any good, and even when I was reporting them, I didn’t report every incident. In January 2013 I ramped up my efforts to raise awareness of this problem and resumed the reports.

All of the buses through 284 listed above have Detroit Diesel Series 50 engines. Buses 402 and above have Caterpillar C9 diesel engines. For additional details on these buses, see The MBTA Vehicle Inventory Page.

In my experience, the fumes in some buses are much worse than in others. I’ve marked with “(m)” in the table above those encounters which seemed minor to me, i.e., although there did seem to be fumes in the passenger compartment, they were much less obvious. If the MBTA puts any effort into dealing with this problem, those are probably not the buses they should deal with first.

Here are the MBTA buses in which I’ve ridden that did not have noticeable diesel fumes in the passenger compartment: 449 (2013/01/10), 450 (2013/01/22), 455 (2013/02/25), 460 (2013/01/14) (o), 496 (2013/01/08), 501 (2013/01/11), 509 (2013/01/11), 549 (2013/01/29), 550 (2013/01/09), 2151 (2013/01/10), 2204 (2013/01/21), 2273 (2013/01/21). Any of these with (o) next to them means that a window was open and therefore the observation is probably not meaningful.

It should be noted that since the precise cause of the fumes entering the passenger compartment is not known, a bus which has this problem may not necessarily exhibit it all the time. For example:

• the MBTA may “fix” a bus, but the problem they fixed may be a recurring one, such that the bus stops being filled with fumes for a while and then starts again;
• fumes may accumulate in the passenger compartment over time, such that the bus is fine when it first goes into service in the morning and gets worse throughout the day (my admittedly subjective observation is that I encounter fume-filled buses much more frequently in the afternoon than in the morning); or
• when the bus is being aerated by open windows and/or an open roof hatch, fumes may be blown out of the bus before they can build up in significant concentrations.