A recent study by the American College of Clinical Engineering found that approximately 80 deaths a year in US hospitals were attributable to issues with medical alarms. I recently stumbled upon the new IEC medical alarms standard (60601-1-8) and was pleased to discover a very clever new system being proposed. Two dimensions of information—function and urgency—are encoded using simple elements of music—harmony, tempo, harmonics, and attack/decay times—in a way that makes decoding them almost natural. The cautionary and low-priority versions of the following melodies are shorter and softer:

Alarm High-Priority Melody Mnemonic
General C4-C4-C4-C4-C4 Fixed pitch
Cardiac C4-E4-G4-G4-C5 Trumpet call; Call to arms; Major chord
Artifical Perfusion C4-F#4-C4-C4-F#4 Artificial sound; Tri-tone
Ventilation C4-A4-F4-A4-F4 Inverted major chord; Rise and fall of the
Oxygen C5-B4-A4-G4-F4 Slowly falling pitches; Top of a major scale;
Falling pitch of an
Temperature C4-E4-D4-F4-G4 Slowly rising pitches; Bottom of a major scale;
Related to slow
increase in energy or temperature
Drug delivery C5-D4-G4-C5-D4 Jazz chord (inverted 9th); Drops of an
infusion falling and
Power failure C5-C4-C4-C5-C4 Falling or dropping down