If you’re on the phone while driving a bus, you shouldn’t be a bus driver.

Cellphones and driving just don’t mix, period. We’ve known for years now, from scholarly research into fatal crashes due to distracted driving, that chatting on your cell while zooming down Lake Shore Drive is dangerous.

That goes double, or triple, when the driver is behind the wheel of a typical 40-foot CTA bus, or even one of those 60-foot “articulated” behemoths, maneuvering an impossibly difficult left-hand turn at a tight and crowded corner.

EDITORIAL

The Chicago Transit Authority no doubt had this in mind nine years ago when it declared “zero-tolerance” for bus drivers and L operators using cellphones, or even having them in their possession, when on-duty and driving.

But as Sun-Times reporter Robert Herguth found, the CTA’s zero tolerance is really anything but.

Since 2009, dozens of bus drivers have been disciplined for violating the policy, but only 13 have been fired or quit. Those 13 don’t include two drivers who crashed their buses while on the phone.

The CTA must get tougher. As unwise as it may be to put one’s own life in danger by talking on a phone or texting while driving, it’s far more irresponsible to put in danger the lives of dozens of passengers on a public bus.

All of us, at some point, will get that emergency call or text while driving. We have to deal with it. And the best way is to pull over to the side of the road — or wait until we get where we’re going. Too much research says to do otherwise is dangerous.

The National Safety Council points out that “drivers using cell phones look but fail to see up to 50 percent of the information in their driving environment.” In other words, we don’t even notice half the stuff we really should see. Hands-free phones, the NSC warns, are risky, too.

Bus drivers know this too, and most of them respect the rules. As a CTA spokesperson pointed out, the violations Herguth uncovered took place “over the course of about 24 million combined bus and rail trips.”

But the relatively few bus drivers who don’t follow the rules have no business behind the wheel.

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