What is the minimum noise-free period required before conducting a baseline audiogram using DD Form 2215?

The minimum noise-free period required before conducting a baseline audiogram using DD Form 2215 is 14 hours. This requirement is in place to ensure that any temporary threshold shifts in hearing caused by noise exposure are minimized. Noise exposure, even at lower levels, can affect the accuracy of audiometric testing. By allowing this duration of quiet, the technician can better establish a true baseline for an individual's hearing capabilities, which is critical for detecting any changes over time that could be indicative of noise-induced hearing loss. Establishing an accurate baseline is essential for monitoring and protecting hearing health, particularly for individuals exposed to hazardous noise environments.