TUNING FORK

Typical Number in Hospital: 50

Cost Bands: 1

References: 8

Tuning forks are used routinely to make a crude assessment of the extent and nature of the patient's deafness. They provide two mechanisms of transmitting sound to the ear:

1. By air conduction. This is the normal mechanism by which sound is radiated from the vibrating forks.

2. By bone conduction. The footplate of the tuning fork is pressed against the patient's forehead or mastoid bone (behind the ear). Sounds are thus transmitted as vibrations through the skull to the inner ear. Tuning forks used in hospitals therefore have a circular footplate (about 2 cm in diameter) whereas tuning forks designed for musical applications have a pointed end.

Hospital tuning forks come in a wide range of frequencies at octave intervals although the most popular are 256 and 512 Hz.