3.5.1 Safety management

Generally, it is not easy to keep employing a technician only for maintaining and operating a centrifuge. Therefore, it would be wise to make your centrifuge system as simple as possible, so that centrifuge users can operate it without deep knowledge in the field of mechanics. In case of PHRI centrifuge, the system detects the failure in electrical and hydraulic works, as well as vibration and noise of the machine. Two stages of response are programed depending on the seriousness of the failure; one is an alarm just locating the failure and another is an emergency forcing to stop the centrifuge. Safety management in terms of software is also quite essential.

For example, the safety management system for Taisei centrifuge is shown pictorially.

Sensor at the entrance

At the loading gate

Photo 1 Inactivation sensors at the entrance and the loading gate. Fail to activate the centrifuge with any open gate. Even if fully closed, you are forced to wait for 30 seconds before triggering the machine. During the period, the pit is filled with ear-piercing buzzer, which would give a chance for a colleague accidentally left in the pit to stop spinning.

CCTV camera

Monitors

Photo 5 Surveillance cameras in the pit and monitors in the operating room. Three cameras are preferable to cover the circular pit.

Terashi, M. and Fujii, N. (1988) : Centrifuge model tests, 4. Fundamental system and data acquisition system for centrifuge, Tsuchi-to-kiso, Vol. 36, No. 1, pp. 79-86 (in Japanese).

Nagura, K., Tanaka, M., Kawasaki, K. and Higuchi, Y. (1994) : Development of an Earthquake Simulator for the TAISEI Centrifuge, Proc. of CENTRIFUGE 94, pp. 151-156.