Strobe lights, pillow shakers and bed shakers as smoke alarm signals

This paper assesses the waking effectiveness of strobe lights and pillow and bed shakers as smoke alarm\ud warning devices and compares them to an auditory signal. The signals were activated at increasing intensity\ud levels during slow wave (deep) sleep in two groups, (i) 38 adults aged 18-77 years with hearing loss of 25-\ud 70 dBA in both ears, and (ii) 32 young adults aged 18 -26 years impaired with alcohol at 0.05 blood alcohol\ud content. Three quarters of both groups slept through the strobe light activated at above the intensity\ud required by the standard whereas a 75 dBA 520 Hz square wave T-3 sound woke over 90%, and at a louder\ud volume 100%. The pillow and bed shakers did not wake 17-20% of the hard of hearing participants at the\ud intensity level as purchased. Hard of hearing participants aged ≥60 years were less likely to wake up to the\ud bed shaker than those aged