The Madrid commuter train bombings that left nearly 200 dead and another 1,200 injured raise severe questions about security on U.S. buses and trains.

One operator, Chicago Sightseeing Co., which operates motorcoaches in the Windy City, is experimenting with a device that could be the answer.

A simple, handheld tool that looks very much like a TV remote prompts an inspector or driver to scour a vehicle from end to end, checking every location where tampering may have occurred or a device hidden. The inspection system was developed by ZONAR Systems, a Seattle firm that created the process to help bus operators perform and document their pre- and post-trip vehicle inspections. But ZONAR and others quickly realized the potential use as a security safeguard.

That’s what Chicago Sightseeing is testing now, according to Christopher Ferrone, the company’s vice president for fleet logistics and engineering. “We already use the ZONAR process to check the physical and mechanical condition of our buses,” he said. “Now we hope to see how it works as a means of assuring security.”

Mike McQuade, director of research and development for ZONAR Systems, explained that small, smart sensors called RFID tags are coded with inspection cues and permanently affixed at strategic points throughout the vehicle. The driver or inspector electronically activates the handheld reader near a sensor and receives a complete inspection agenda for that zone. For example, the bus interior checklist would call for inspecting beneath seats for extraneous parcels or boxes.

“The inspector can’t miss any zone or component because he or she is prompted every time. A condition status must be entered at each checkpoint,” McQuade said. Missing a zone becomes obvious at the end of the check and when the information is downloaded into the central database.

Ferrone reinforced the importance of total, verified coverage. “The ultimate benefit of the ZONAR system is 100% confirmation that every element of the inspection has been completed,” he said.

McQuade said that the Department of Homeland Security (DHS) also has been looking at the ZONAR system for possible applications on all forms of public ground transportation.

Motorcoach operators are eligible for grants to upgrade security and “the ZONAR system is in DHS’ highest priority funding category,” McQuade noted. “Invariably, users of this technology report dramatic improvements in safety while enjoying the many cost-saving efficiencies of a paperless system. There’s no doubt that verified visual inspections will greatly improve transportation security as well.”