The accelerations Steve mentions (both the observed figures of .12g and the .15g trigger threshold) seem remarkably high. They are well within the range associated with MM VII (.10 - .15g): "Everybody runs outdoors. Damage negligible in buildings of good design and construction; slight to moderate in well-built ordinary structures; considerable in poorly built or badly designed structures; some chimneys broken. Noticed by persons driving cars." And - since this is a P-wave detector, the accelerations of the following S-waves would be even greater for most (all?) quakes. It would hardly seem necessary to have a detector unless one is a very hard sleeper! I am inferring that Steve's reported accelerations were P-wave accelerations, since he says: "So, it was seeing P-wave of the right amplitude of an incoming EQ and triggering, even though the actual event didn't occur."

Do the owners have a cat?

MW
93420