title: [Failure analysis of medical linear accelerator with reliability analyses].
abstract: We analyzed a number of cases about the Linac troubles in our hospital and have examined the effect of preventive maintenance with Weibull analysis and exponential distribution from April 2001 to March 2012. The total failure by irradiation disabled was 1, 192. (1) Medical linear accelerator (MLC) system was 24.0%, (2) radiation dosimetry system 13.1%, and the (3) cooling-water system was 26.5%. It accounts for 63.6% of the total number of failures. Each parameter value m, which means the shape parameter, and the failure period expectancy of parts μ were (1) 1.21, 1.46/3.9, 3.8 years. 3.7, 3.6 years. (2) 2.84, 1.59/6.6, 4.3 years. 6.7, 5.9 years. (3) 5.12, 4.16/6.1, 8.5 years. 6.1, 8.5 years. Each shape parameter was m>1. It is believed that they are in the worn-out failure period. To prevent failure, MLC performance should be overhauled once every 3 years and a cooling unit should be overhauled once every 7 years. Preventive maintenance is useful in assessing the failure of radiation therapy equipment. In a radiation dosimetry part, you can make a preemptive move before the failure by changing the monitor's dosimeter board with a new part from the repairs stockpiled every 6 months for maintenance.
authors: Department of Radiological Technology, Showa University Northern Yokohama Hospital.
authors: Ken
authors: K
authors: Zakimi
authors: Hiroyuki
authors: H
authors: Watanabe
authors: Hideki
authors: H
authors: Ishida
authors: Toshio
authors: T
authors: Take
authors: Mitsuyoshi
authors: M
authors: Kato
authors: Tsugunori
authors: T
authors: Iwai
authors: Masaru
authors: M
authors: Nitta
authors: Kyouichi
authors: K
authors: Kato
authors: Yasuo
authors: Y
authors: Nakazawa
mesh_terms: D004868:Equipment Failure; D019544:Equipment Failure Analysis / Q000379:methods*; D008283:Maintenance; D010315:Particle Accelerators; D015203:Reproducibility of Results; D013997:Time Factors