According to ANSI standards, spl measures are typically how many decibels higher than hl measures?

In audiometric testing, ANSI standards indicate that sound pressure level (SPL) measurements are generally 20 decibels higher than hearing level (HL) measurements. This difference arises because HL is a reference level specifically tailored to reflect the average hearing sensitivity of young adults, while SPL measures the actual sound pressure in the environment.

When using SPL, the measurements relate to physical acoustical energy, while HL is a relative measure based on the thresholds of hearing for individuals. Therefore, a 20 dB difference between SPL and HL is considered standard, making it essential for audiologists and hearing professionals to understand this distinction in order to assess hearing accurately and prescribe appropriate amplifications or interventions for patients. Understanding the relationship between these measurements helps professionals align sound levels during hearing assessments and fittings.