scope:

Description of Driving Event:

The fans are located on the 107 foot level of the rotating service structure (RSS) and controlled from the computer console for ECS in the PTCR. The circuit breakers providing power to the fans are located in the hoist room on the 207 foot level of the RSS; therefore, there is no local control. When maintenance personnel are working on the fans, it is possible that someone could re-apply power to them. Also, if local switches were located immediately outside the locked fan rooms, should a problem arise with the fans that generated excessive noise, smoke, etc. They could be shut down by personnel and reduce damage.