Dear Alice, Until recently I lived in Tokyo and commuted on the JR Chuo Sobu Line from Kameido Station. I made it a practice to ride in the last compartment of the train, just so I could enjoy the spectacle of the driver making those sincere hand gestures at each and every station. I've seen the same thing on other train and subway lines, so I'm sure there is a very good reason they do this. But what the heck is it?

Madhu S., Chennai, India

Dear Madhu,

For the benefit of readers who have never been on a Japanese train, or have missed all the fun by riding in the wrong car, I should explain that the trains you used to ride were 10 cars long and operated by two employees: a driver in the front and a conductor in the back. Since you were in the last car, it was actually the conductor you were watching. And I know just what you saw: an employee in a neat uniform and cap, all alone yet apparently engaged in animated conversation while making vigorous gesticulations. It is indeed a spectacle, and anyone witnessing it for the first time might well wonder if there's a madman at the controls.

Fortunately, there's method to the madness. Those odd vocalizations and gestures help keep us safe by heightening workers' mental focus at key points on the job where accidents are likely to occur. This technique for error-prevention is called shisa kanko, although you may hear variants such as shisa kakunin kanko and yubisashi kosho. It's hardly known outside of Japan, but those who do talk about it in English use the term "pointing and calling."

Japanese railway employees have been using this technique for more than 100 years, but the exact origin is a little unclear. One story traces it to the early 1900s and a steam-train engineer named Yasoichi Hori, who was supposedly starting to lose his sight. Worried that he'd go through a signal by mistake, Hori began to call out the signal status to the fireman riding with him. The fireman would confirm it by calling back. An observer decided this was an excellent way of reducing error, and by 1913 it was encoded in a railway manual as kanko oto ("call and response"). The pointing came later, probably after 1925.

To give an example with English calls, let's say your task is to make sure a valve is open. You look directly at the valve and confirm it's open. You call out in a clear voice, "Valve open!" Then, still looking at the valve, you draw your right hand back, point to the valve in an exaggerated way and call out, "OK!" The theory is that hearing your own voice, and engaging the muscles of the mouth and arm, stimulates your brain so you're more alert.

But does it actually work? I posed that question to Kazumi Tabata of the Japan Industrial Safety and Health Association, who showed me research conducted in 1994 by the Railway Technical Research Institute. Workers asked to complete a simple task made 2.38 errors per 100 actions when no special steps were taken to prevent errors. When told to add just calling or just pointing, their error rate dropped significantly. But the greatest reduction in error — to just 0.38 mistakes per 100 actions — was achieved when workers used both steps together. The combination of pointing and calling reduced mistakes by almost 85 percent.

Pointing and calling has now been adopted by a wide range of Japanese industries and businesses, largely because JISHA has been teaching it since the '80s as part of a comprehensive program to reduce on-the-job accidents. But there hasn't been much interest in pointing and calling overseas.

"The emphasis in Europe and the United States has generally been more on reducing accidents by changing machinery and systems, while in Japan it's been more on improving operator accuracy," Tabata explained. "But you really need to look at both aspects."

In his book "Shippai no Shinrigaku (The Psychology of Error)" (Nihon Keizai Shinbunsha, 2004), Shigeru Haga, a professor at Rikkyo University in Tokyo, mentioned attempts to introduce pointing and calling in Japanese factories overseas and wrote: "Gaikoku no hito ni nakanaka yatte moraenai yo desu" ("It seems it's difficult to get foreigners to do it"). Haga didn't say why, but my guess is that workers who have never seen pointing and calling feel silly doing it. Even in Japan, companies have to put a lot of effort into getting workers over the initial embarrassment.

My last stop was JR East Japan Railways' headquarters in Shinjuku, because I was desperate to know what the heck I'm hearing when conductors do their calls. Hisashi Satoh, who oversees safety training at JR East, ran me through a few Sobu Line specifics. After the train has stopped, but before the conductor opens the door, you may hear "Jyuryo teishi ichi, yoshi!" which means "Ten-car stop position, OK!" Another call you're likely to hear, just before the conductor activates the door-closing bell, is "Repita yoshi!" literally, "Repeater, OK!" (A "repeater" is a signal in the conductor's position that repeats the signal the driver is seeing at the front of the train.)

Before I made tracks, I asked Satoh about cell phones. Just that morning, news had come out that the driver in the Sept. 12 Los Angeles train accident that killed 26 people had been sending text messages just before the crash. Much to my relief, Satoh said that JR East has a strict rule that employees may not even carry personal cell phones, let alone use them, when working on trains. A driver or conductor found to have used a personal cell phone on the job, he assured me, would be fired.

Now that's a good call.

To learn more about pointing and calling, visit www.jaish.gr.jp/hpvod/index_011_e.html where you can watch a free online video in good English. It's in three 15-minute parts (E10, E11 and E12). You can also view the videos from 9:30 a.m. to 4:30 p.m. on weekdays on the second floor of JISHA's Industrial Safety Museum (5-35-1 Shiba, Minato-ku, Tokyo; (03) 3452-6431). That's near Tamachi Station and admission is free. Puzzled by something you've seen? Send a description, or better yet a photo, to [email protected] or A&E Dept., The Japan Times, 4-5-4 Shibaura, Minato-ku, Tokyo 108-8071.