Here's how drug testing works at the Tour de France, the world's greatest race

MONTAUBAN, France, July 10 — Each day here at the Tour de France a handful of the world's fittest athletes climb into a small office on wheels to pee into a plastic cup. For the riders it is part of the job, as routine as riding their bikes, but for a sport not long ago plagued by doping scandals the testing is critical to its integrity and survival.

There has not been a doping positive in this Tour so far. In last year's race there was one positive, for cocaine, and in the 2014 Tour there was no positive test reported. (Here's a list of doping cases in cycling.)

At least on the surface, pro cycling today appears much cleaner than it did a decade or so ago.

How does the world's biggest bike race detect if a rider is doping? Welcome to "antidoping control," where officials try to ensure that cyclists are racing clean by testing their urine and blood, usually with little notice. If a rider fails to report to antidoping, for whatever reason, he is considered to be positive and immediately kicked out of the race.

This week at the Tour, cycling’s governing body, the Union Cycliste Internationale (UCI), and the Cycling Anti-Doping Foundation (CADF), the independent organization mandated by the UCI to define and carry out the antidoping strategy in cycling, granted Business Insider access into their mobile antidoping-control facility. Here's what we saw:

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Before each stage finishes, an official from the Cycling Anti-Doping Foundation (CADF) posts a list of riders' numbers near the finish line.

Teams send a representative — usually a soigneur— to check the list to see if one of their riders has been selected for testing. Meanwhile, CADF chaperones are sent to the finish to notify the selected riders and escort them to antidoping.

The riders' names are not printed on the list but their race numbers and team names are.

It isn't hard to figure out who's who as the riders' race numbers and names are public knowledge. A quick Google search will easily identify each rider. The riders don't have to go directly to antidoping, so if they are asked to do a postrace press conference or wish to go to their team bus and clean up, they can do that — as long as they are with their assigned chaperone at all times.

The antidoping control is usually located just beyond the finish line.