Why is your commuter rail train delayed or canceled? Hank Phillippi Ryan’s exclusive investigation found it could be because the engineer is afraid to drive it.

When we staked out local commuter rail trains at random we found engineers driving locomotives wearing masks over their faces. Different days, different trains and different engineers wearing masks.

What are the masks protecting engineers from? A potentially hazardous substance they say is leaking into some driving compartments.

A commuter rail employee sent Hank a video of white stuff swirling in the air inside a locomotive driving compartment and says it’s very fine sand.

The sand, made up of the mineral silica, is supposed to stay in a box outside the locomotive so engineers can drop it directly onto the tracks if they need traction.

But on some locomotives, engineers say, the silica sand is getting inside.

The problem: breathing in tiny particles of that silica sand can be dangerous.

An employee also sent Hank a picture of the bag the sand comes in.

There’s a printed warning on it that says: “Never breathe dust.” “May cause cancer by inhalation.” “Causes damage to organs through prolonged or repeated exposure by inhalation.”

A retired engineer who worked on MBTA trains told Hank that he first reported sand leaks like this five years ago to his then-employer, Keolis. That’s the company that operates the commuter rail for the T. He alerted federal safety officials as well.

“It was like being in a dust storm a sandstorm and you couldn’t escape from it. It was in the air conditioning and the heating vents it was blowing everywhere in the cab,” the retired engineer says. “You could taste the grit in your teeth from the sand it was so bad. You would get little particles in your eyes they would hurt, turn red. I’d have to rinse my eyes several times and breathing it in it would make it hard to breathe.”

Current engineers, who wouldn’t talk on camera for fear of getting fired, tell us they’re worried about their health.

Keolis, after our questions, admitted there have been complaints about leaking sand in one type of locomotive since 2015.

Back then the company says it, “cleaned out the cabs and took other steps to mitigate the issue.”

But workers recently started taking pictures and complaining again about leaking sand.

As a result, Keolis says they had four air quality tests done. They told us the tests showed “no detectable health hazards, silica or otherwise.”

Still, the company is now offering these masks to engineers who “choose to use them.” Not all engineers we saw are wearing them, but many are.

“To offer an engineer a mask is crazy and this is very dangerous product when its breathed into the lungs, this could cause cancer long term,” the retired engineer told Hank.

As for commuters: Keolis told us the sand is not getting into the passenger cars.

But we found riders are affected in a different way: we’ve learned some trains have recently been delayed or canceled because engineers refused to drive locomotives that are leaking sand.

“I think it’s terrible why should someone have to risk their lives when they go to work,” the retired engineer told Hank.

Keolis would not release the air quality tests to us. But they say they’re taking these complaints seriously and are working to fix the problem.

If you have a tip or story idea for Hank email her at TellHank@whdh.com

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