As a motorist in a passenger vehicle, have you ever sped by a bicyclist within mere inches of that rider as he or she was traveling in a bike lane or on the shoulder of a road? Candor is appreciated here; it happens.

Conversely, have you ever been similarly situated with the above-described bicyclist, that is, tooling along and suddenly terrified for your life owing to thousands of pounds of steel that is hurtling by and that has seemingly missed striking you only because of some intervening miracle?

Facts are facts. Bicyclists across California are singularly vulnerable every time they straddle a bike. Riding a bike is a wonderful pastime, of course (and a necessary conveyance for many riders), but it is not an activity to be pursued by anyone — adult or kid — who isn’t bringing their A-game.

And even for riders who are, a little extra help is needed from the drivers of motorized vehicles.

Thus, the so-called “buffer” law, which some of our readers in Los Angeles and elsewhere might be unfamiliar with.

In fact, and as noted in a recent article on California bicycle legislation and rider safety, many drivers across the state apparently have no idea that a law was passed more than a year ago that requires passenger-vehicle drivers to keep at least three feet away from bicyclists.

If you’re one of those people, take note: That law exists and is enforceable, although the citations that have been issued to drivers thus far for violating the three-foot zone can almost be counted on one hand.

“I’m not totally surprised; we are disappointed,” says one bike advocate commenting on the paucity of citations handed out.

Notwithstanding the lack of enforcement, the law may be having some positive effect. The California Highway Patrol reports that bike-motor vehicle collisions across the state have decreased somewhat over the past couple of years.