15A NCAC 02D .1808 EVALUATION OF NEW OR MODIFIED SWINE FARMS (a) Purpose. The purpose of this Rule is to specify the methods for evaluating new or modified swine farms for compliance with the performance standard in G.S. 143-215.10I (b)(3). (b) Applicability. This Rule applies to new or modified swine farms required by G.S. 143-215.10I to meet the performance standard in G.S. 143-215.10I (b)(3). (c) Requirements. New or modified swine farms subject to this rule shall comply with the requirements in this Section. (d) Evaluation of new or modified swine farms. For the purpose of evaluating odor at new or modified swine farms for compliance with the performance standard in G.S. 143-215.10I (b)(3), the following shall apply: (1) (2) History Note: When a field olfactometry method and instrumentation is used to determine odor intensity at the designated evaluation location, as specified in Rule .1802(e) of this Section, the measured dilution-tothreshold ratio shall be less than or equal to 7:1 as determined using the manufacturer's instrument procedures and instructions; or When odor intensity is determined using an Odor Intensity Referencing Scale (OIRS) as specified in ASTM 544-99, the instantaneous observed level shall be less than the equivalent of 225 parts per million n-butanol in air. In addition, the average of 30 consecutive observations conducted over a minimum of 30-minutes at designated evaluation locations shall be less than the equivalent of 75 parts per million n-butanol in air and a minimum of four readings out of the minimum 30 readings shall be less than or equal to the equivalent 25 parts per million n-butanol in air. Authority G.S. 143-215.10I; 143-215.3(a)(1); 143-215.107(a)(11); 143-215.108(a); Eff. January 1, 2009.