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Subpart 257-6: Ambient Air Quality Standard-Hydrocarbons (Non-Methane)

(Statutory Authority: Environmental Conservation Law, § 15)

[Filed 2/16/77. Effective 30 days after filing.]

[This is page 1 of 1 of this Subpart. A complete list of Subparts in this regulation appears in the Chapter 3 contents page. A list of sections in this Subpart appears below.]

For administrative information about this posting, contact: Division of Air Resources. The Bureau of Air Quality Planning at (518) 402-8396 or the Bureau of Stationary Sources at (518) 402-8403 is the contact for technical questions pertaining to this rule.



§257-6.1 Definition

Hydrocarbons are organic compounds consisting only of hydrogen and carbon. However, for the purpose of this Subpart, hydrocarbons (non-methane) shall refer to the total air borne hydrocarbons and other organic compounds excluding methane (CH4) as measured by the specified technique, or other method acceptable to the commissioner.

§257-6.2 Objective

Although ambient air concentrations of gaseous hydrocarbons as a group have not been associated with health effects, it has been demonstrated that ambient levels of photo-chemical oxidant which do have adverse effects on health are associated with the occurrences of concentrations of non-methane hydrocarbons. The objective of this standard is to inhibit such photochemical reactions which lead to photochemical smog formation.

§257-6.3 Standard

During the three-hour period from 6 to 9 a.m., the average non-methane hydrocarbon concentration must not exceed 0.24 ppm1 more than once in any 12 consecutive months.


1Corresponds to Federal standard of 160 µg/m3 (at temperature of 25oC and pressure of 760 mm of mercury).

§257-6.4 Measurement

(a) Hydrocarbons (non-methane) is determined by the flame ionization technique with correction for methane by a methane analyzer.

(b) All measurements are corrected to a reference temperature of 25 degrees Centigrade and to a reference pressure of 760 millimeters of mercury.