Establish operating limit
(d) Establish operating limit. For each operating parameter that must be monitored in 63.11925(c) for process vent control devices, you must establish an operating limit as specified in paragraphs (d)(1) through (4) of this section. You must establish each operating limit as an operating parameter range, minimum operating parameter level, or maximum operating parameter level as specified in Table 7 to this subpart. Where this subpart does not specify which format to use for your operating limit (e.g., operating range or minimum operating level), you must determine which format is best to establish proper operation of the control device such that you are meeting the emission limits specified in Table 1 or 2 to this subpart. (1) For process vent control devices, the operating limit established for each monitored parameter specified in 63.11940 must be based on the operating parameter values recorded during any performance test conducted to demonstrate compliance as required by 63.11925(d)(4) and (e)(4) and may be supplemented by engineering assessments and/or manufacturer's recommendations. You are not required to conduct performance tests over the entire range of allowed operating parameter values. The established operating limit must represent the conditions for which the control device is meeting the emission limits specified in Table 1 or 2 to this subpart. (2) You must include as part of the notification of compliance status or the operating permit application or amendment, the information in paragraphs (d)(2)(i) through (iv) of this section, as applicable, for each process vent control device requiring operating limits. (i) Descriptions of monitoring devices, monitoring frequencies and operating scenarios. (ii) The established operating limit of the monitored parameter(s). (iii) The rationale for the established operating limit, including any data and calculations used to develop the operating limit and a description of why the operating limit indicates proper operation of the control device. (iv) The rationale used to determine which format to use for your operating limit (e.g., operating range, minimum operating level or maximum operating level), where this subpart does not specify which format to use. (3) For batch processes, you may establish operating limits for individual batch emission episodes, including each distinct episode of process vent emissions or each individual type of batch process that generates wastewater, if applicable. You must provide rationale in a batch precompliance report as specified in 63.11985(c)(2) instead of the notification of compliance status for the established operating limit. You must include any data and calculations used to develop the operating limits and a description of why each operating limit indicates proper operation of the control device during the specific batch emission episode. (4) If you elect to establish separate operating limits for different batch emission episodes within a batch process as specified in paragraph (d)(3) of this section, you must maintain daily records indicating each point at which you change from one operating limit to another, even if the monitoring duration for an operating limit is less than 15 minutes. You must maintain a daily record according to 63.11990(e)(4)(i).