Swedish investigators are advising that "sterile operation" guidelines be developed for air traffic controllers following an incident in which a vehicle almost strayed onto the runway as a Brussels Airlines flight was departing.
The concept of a sterile environment, already familiar to pilots, restrict all interactions and conversations exclusively to immediate operational matters in order to reduce distraction.
While Swedish investigation authority SHK says an unconditional prohibition of conversation between controllers under varying workloads is "unlikely to be viable", it says introducing a sterile concept "would help enhance flight safety" and is recommending that air navigation service LFV draws up clear guidelines.
The near-incursion incident, involving a BAE Systems Avro RJ85, occurred at Gothenburg Landvetter airport on 8 September last year after a handover between tower controllers resulted in their losing track of a service car's location.
SHK says the car had been incorrectly identified as being at position Kiosk 211, close to the threshold of runway 21. But while the car had been in this area it had already returned to a service road station near the midpoint of the runway.
The inquiry says that "private chatter" between controllers had taken place while the car's position was changing.
After the RJ85 was granted take-off clearance from runway 21, the service car was permitted to enter the runway - theoretically behind the aircraft. The car, however, was approaching an entry point in front of the jet and stopped only after the driver saw "a flash of light" from his left and heard the sound of engines.
SHK says the car was 27m (90ft) from the runway at the time and stopped about 40m from the jet's take-off point.