Tuesday's very hot temperatures caused MBTA commuter rail restrictions and delays, causing them to move slower and resulting in delays and headaches.

"It will go slower," said one commuter.

"It takes a lot longer to get home than it used to," said another.

From 1-7 p.m. Tuesday, the MBTA warned of rail restrictions due to the heat on the Framingham/Worcester line. Those delays cost commuters on some trains at least 20 minutes of their time.  

The reason why? If the tracks get too hot, a train could possibly derail.

"If the lines were to expand, and we haven't seen any of that, it would be horrible," said Mac Daniel of Keolis Commuter Services, the company which operates the MBTA's commuter rail.

Daniel says MBTA workers take the temperature of both the air and tracks daily.

If a train must be slowed down, it's slowed quite considerably. Daniel said the trains are limited to a top speed of between 30 and 40 miles per hour in the restriction.

He said it "slows their commute terribly."

In particular, the Framingham/Worcester line is delayed most often due to heat because the tracks are old freight tracks.

"Because it's an old freight line and because the other lines around Boston have been built strictly for commuter rail, or have been de-stressed, which basically more or less expands the lines from many expansion problems, that's why the heat restrictions are in place," Daniel explained.

Other lines can also have rail restrictions if there's a heat wave of about 100 degrees.

Daniel wants to reaffirm commuters that they're not seeing any damage to the tracks, but rather the restrictions are just purely precautionary measures. Plans are already in place to upgrade a portion of the tracks on Framingham/Worcester line on July 21, he says, and more work should be complete by next year.

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