Sound Pressure Level

{
  "id": "MLC-T-ENV-026169",
  "term": "Sound Pressure Level",
  "field": "Environment",
  "definition": "1. Level, in decibels, calculated as 20 times the common logarithm of the ratio of a sound pressure to the reference sound pressure of 20 micropascals.\n\n2. In decibels, 20 times the logarithm to the base ten of the ratio of a sound pressure to the reference sound pressure of 20 micropascals (20 micronewtons per square meter). In the absence of any modifier, the level is understood to be that of a root-mean-square pressure.\n\n3. Decibels, 20 times the logarithm to the base 10 of the ratio of a sound pressure to the reference sound pressure of 20 micropascals (20 micronewtons per square meter). In the absence of any modifier, the level is understood to be that of a root-mean-square pressure. The unit of any sound level is the decibel, having the unit symbol dB.",
  "references": [
    "40 CFR 201.1 (2013 CFR)",
    "40 CFR 204.2 (2013 CFR)",
    "40 CFR 205.2 (2013 CFR)"
  ],
  "url": "https://mlchart.com/terminology/environment/sound-pressure-level/"
}