U.S. Code of Federal Regulations
Regulations most recently checked for updates: Jan 21, 2026
§ 98.510 - Definition of the source category.
This source category includes any facility that produces caprolactam, glyoxal, or glyoxylic acid. This source category excludes the production of glyoxal through the LaPorte process (i.e., the gas-phase catalytic oxidation of ethylene glycol with air in the presence of a silver or copper catalyst).
§ 98.511 - Reporting threshold.
You must report GHG emissions under this subpart if your facility meets the requirements of either § 98.2(a)(1) or (2) and the definition of source category in § 98.510.
§ 98.512 - GHGs to report.
(a) You must report N
(b) You must report under subpart C of this part the emissions of CO
§ 98.513 - Calculating GHG emissions.
(a) You must determine annual N
(b) You must determine the total annual amount of product i (caprolactam, glyoxal, or glyoxylic acid) produced on each process line t (metric tons product), according to § 98.514(b).
(c) If process line t exhausts to any N
(1) Use the control device manufacturer's specified destruction efficiency.
(2) Estimate the destruction efficiency through process knowledge. Examples of information that could constitute process knowledge include calculations based on material balances, process stoichiometry, or previous test results provided the results are still relevant to the current vent stream conditions. You must document how process knowledge (if applicable) was used to determine the destruction efficiency.
(d) If process line t exhausts to any N
(1) If the abatement technology j has no downtime during the year, use 1.
(2) If the abatement technology j was not operational while product i was being produced on process line t, calculate the abatement utilization factor according to equation 1 to this paragraph (d)(2).
(e) You must calculate N
(f) You must determine the annual emissions combined from each process line at your facility using equation 3 to this paragraph (f):
§ 98.514 - Monitoring and QA/QC requirements.
(a) You must determine the total monthly amount of caprolactam, glyoxal, and glyoxylic acid produced. These monthly amounts are determined according to the methods in paragraph (a)(1) or (2) of this section.
(1) Direct measurement of production (such as using flow meters, weigh scales, etc.).
(2) Existing plant procedures used for accounting purposes (i.e., dedicated tank-level and acid concentration measurements).
(b) You must determine the annual amount of caprolactam, glyoxal, and glyoxylic acid produced. These annual amounts are determined by summing the respective monthly quantities determined in paragraph (a) of this section.
§ 98.515 - Procedures for estimating missing data.
A complete record of all measured parameters used in the GHG emissions calculations is required. Therefore, whenever a quality-assured value of a required parameter is unavailable, a substitute data value for the missing parameter must be used in the calculations as specified in paragraphs (a) and (b) of this section.
(a) For each missing value of caprolactam, glyoxal, or glyoxylic acid production, the substitute data must be the best available estimate based on all available process data or data used for accounting purposes (such as sales records).
(b) For missing values related to the N
§ 98.516 - Data reporting requirements.
In addition to the information required by § 98.3(c), each annual report must contain the information specified in paragraphs (a) through (j) of this section.
(a) Process line identification number.
(b) Annual process N
(1) N
(2) N
(3) N
(c) Annual production quantities from all process lines at the caprolactam, glyoxal, or glyoxylic acid production facility according to paragraphs (c)(1) through (3) of this section.
(1) Caprolactam production (metric tons).
(2) Glyoxal production (metric tons).
(3) Glyoxylic acid production (metric tons).
(d) Annual production capacity from all process lines at the caprolactam, glyoxal, or glyoxylic acid production facility, as applicable, in paragraphs (d)(1) through (3) of this section.
(1) Caprolactam production capacity (metric tons).
(2) Glyoxal production capacity (metric tons).
(3) Glyoxylic acid production capacity (metric tons).
(e) Number of process lines at the caprolactam, glyoxal, or glyoxylic acid production facility, by product, in paragraphs (e)(1) through (3) of this section.
(1) Total number of process lines producing caprolactam.
(2) Total number of process lines producing glyoxal.
(3) Total number of process lines producing glyoxylic acid.
(f) Number of operating hours in the calendar year for each process line at the caprolactam, glyoxal, or glyoxylic acid production facility (hours).
(g) N
(h) Monthly abatement utilization factor for each N
(i) Number of times in the reporting year that missing data procedures were followed to measure production quantities of caprolactam, glyoxal, or glyoxylic acid (months).
(j) Annual percent N
(1) Annual percent N
(2) Annual percent N
(3) Annual percent N
§ 98.517 - Records that must be retained.
In addition to the information required by § 98.3(g), you must retain the records specified in paragraphs (a) through (d) of this section for each caprolactam, glyoxal, or glyoxylic acid production facility:
(a) Documentation of how accounting procedures were used to estimate production rate.
(b) Documentation of how process knowledge was used to estimate abatement technology destruction efficiency (if applicable).
(c) Documentation of the procedures used to ensure the accuracy of the measurements of all reported parameters, including but not limited to, calibration of weighing equipment, flow meters, and other measurement devices. The estimated accuracy of measurements made with these devices must also be recorded, and the technical basis for these estimates must be provided.
(d) The applicable verification software records as identified in this paragraph (d). You must keep a record of the file generated by the verification software specified in § 98.5(b) for the applicable data specified in paragraphs (d)(1) through (4) of this section. Retention of this file satisfies the recordkeeping requirement for the data in paragraphs (d)(1) through (4) of this section.
(1) Monthly production quantity of caprolactam from each process line at the caprolactam, glyoxal, or glyoxylic acid production facility (metric tons).
(2) Monthly production quantity of glyoxal from each process line at the caprolactam, glyoxal, or glyoxylic acid production facility (metric tons).
(3) Monthly production quantity of glyoxylic acid from each process line at the caprolactam, glyoxal, or glyoxylic acid production facility (metric tons).
(4) Destruction efficiency of N
