Natural Condition

{
  "id": "MLC-T-ENV-018237",
  "term": "Natural Condition",
  "field": "Environment",
  "definition": "1. Naturally occurring phenomena that reduce visibility as measured in terms of light extinction, visual range, contrast, or coloration.\n\n2. Reflect naturally occurring phenomena that reduce visibility as measured in terms of light extinction, visual range, contrast, or coloration, and may refer to the conditions on a single day or a set of days. These phenomena include, but are not limited to, humidity, fire events, dust storms, volcanic activity, and biogenic emissions from soils and trees. These phenomena may be near or far from a Class I area and may be outside the United States.",
  "references": [
    "40 CFR 51.301 (CFR 2013)",
    "40 CFR 51.301 (CFR 2017)"
  ],
  "url": "https://mlchart.com/terminology/environment/natural-condition/"
}