Total Hydrocarbon Equivalent
Total Hydrocarbon Equivalent means the sum of the carbon mass contributions of non-oxygenated hydrocarbons, alcohols and aldehydes, or other organic compounds that are measured separately as contained in a gas sample, expressed as petroleum-fueled engine hydrocarbons. The hydrogen-to-carbon ratio of the equivalent hydrocarbon is 1.85:1.
40 CFR § 94.2
The definitions of this section apply to this subpart. They also apply to all subparts of this part, except where noted otherwise.