Reproducing the accidents
Tyler, 1986: Malfunction 54
- Type a patient name, RETURN, and RETURN again for the treatment mode.
- BEAM TYPE: X RETURN. The machine starts setting its bending magnets, which takes 8 seconds. The rest has to happen within those 8 seconds.
- Press RETURN ten times, quickly. Each one accepts the value from the treatment plan or the room, and the cursor ends up on COMMAND.
- Press ↑ eleven times to get back to BEAM TYPE (holding it repeats). Type E RETURN.
- Now take your time: RETURN back down to COMMAND, wait for BEAM READY, and type B RETURN.
The screen says ELECTRON, but the machine fired X-ray current with the turntable in the electron position. It shows MALFUNCTION 54, TREAT PAUSE and 6 monitor units. P RETURN does it again.
The edit is only missed if it lands after the first magnet and before the last. Open "What the operator couldn't see" to watch the magnets. If you are too slow, the machine notices the edit and sets the magnets again for electrons. It says DATA ENTRY for another 8 seconds, then BEAM READY, and the treatment is safe. That is the software working as intended.
Yakima, 1987: Class3 overflow
- Enter an X-ray prescription down to COMMAND, as above, without the edit.
- Press FIELD LIGHT on the hand control. SYSTEM says PRESS SET BUTTON.
- Open "What the operator couldn't see" and press SET (or type SET RETURN) when Class3 is between about 240 and 254.
- If BEAM READY appears, type B RETURN. You get FLATNESS and no dose on the monitor.
Keys: Enter is RETURN, Backspace is BACK SPACE, Insert is LINE FEED, F1–F4 are PF1–PF4, Scroll Lock is NO SCROLL. R RETURN resets.