MULTIX TOP ACSS P

Additional Manufacturer Narrative

SIEMENS IS CONDUCTING AN INVESTIGATION OF THIS EVENT. THE CONCERNED COLLIMATOR IS BUILT OUT OF INFLAMMABLE MATERIALS ACCORDING TO UL STANDARDS AND IT WILL SELF-EXTINGUISH IN CASE OF THERMAL EFFECTS. THIS BEHAVIOR WAS CONFIRMED DURING LAB TESTING. A SUPPLEMENTAL REPORT WILL BE SUBMITTED OF ADDITIONAL INFORMATION BECOMES AVAILABLE. INTERNAL ID # (B)(4).

Description of Event or Problem

SIEMENS WAS INFORMED BY ITS SERVICE ORGANIZATION THAT THE USER RECOGNIZED FIRE AND SMOKE COMING OUT OF THE COLLIMATOR ON THE MULTIX TOP ACSS P SYSTEM. THE USER PUT THE FIRE OUT WITH AN EXTINGUISHER. SIEMENS IS UNAWARE OF ANY PATIENT INVOLVEMENT. THERE ARE NO INJURIES ATTRIBUTE TO THIS INCIDENT.

Additional Manufacturer Narrative

THE ISSUE WAS INVESTIGATED IN DETAIL. THE INVESTIGATION OF THE RETURNED COLLIMATOR SHOWED A SHORT CIRCUIT OCCURRED AT THE PCB D22 BOARD. THE FRONT PANEL AND THE DISPLAY WERE ONLY AFFECTED BY THE THERMAL OVERHEAT ON THE PCB D22 BOARD. A DETAILED EXAMINATION OF THE D22 BOARD INDICATED THAT THE SHORT CIRCUIT ITSELF WAS LOCALIZED BETWEEN THE LAYERS OF THE POWER SUPPLY INPUT. THIS LED TO THE FAULTY CURRENT, WHICH WAS NOT HIGH ENOUGH TO TRIGGER THE PROTECTIVE FUSE OF THE SYSTEM, RESULTING IN THERMAL OVERHEATING. IN GENERAL, THE D22 BOARD IS BUILT WITH 8 LAYERS AND DESIGNED ACCORDING TO MFR 290/020. THE PCB MATERIAL IS FR4 AND UL LISTED WITH THE FLAMMABILITY CLASS UL94-V0. ON THE BOARD ONLY UL LISTED PARTS ARE USED - THESE PARTS ARE NOT FLAMMABLE OR WILL SELF-EXTINGUISH IN CASE OF THERMAL EFFECTS. THIS ENSURES THAT A POTENTIAL IGNITION IS INHIBITED DUE TO THE SELF-EXTINGUISHING BEHAVIOR. THIS EFFECT WAS ALSO CONFIRMED IN TEST LAB. AS AN ADDITIONAL SAFETY MEASURE, THE AFFECTED PCB IS MOUNTED IN THE COLLIMATOR HOUSING AND THE HOUSING MATERIAL HAS ALSO THE FLAMMABILITY CLASS UL94- V0. AFTER REPLACEMENT OF THE COLLIMATOR EQUIPPED WITH A NEW D22 BOARD THE SYSTEM WAS BROUGHT BACK TO SPECIFICATIONS.