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Definition of Ambient Temperature for EPCRA 312 Reporting

The Tier II Hazardous Chemical Inventory form, used to meet annual EPCRA section 312 reporting requirements, requires facility owners or operators to note whether reported hazardous chemicals are present at, above, or below ambient temperature. What is meant by ambient temperature?

Ambient temperature means that the material is stored in the same temperature range as that of the surrounding area. Outdoor storage tanks that are heated or cooled to counter the variation in temperature should also be classified as ambient. However, a tank maintained at a high (or low) temperature not close to the normal range of temperatures of the region should be noted as greater (or less) than ambient temperature.