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Louisiana Register Citations in the Louisiana SIP-Approved rules in this web site

Louisiana Register Citations in the Louisiana SIP-Approved rules in this web site

     At the end of each section in the Louisiana Administrative Code, Title 33:III, Environmental Quality: Air (LAC 33:III, Air), is a HISTORICAL NOTE which contains a list of Louisiana Register (LR) citations promulgating the section and amendments to the section.  This HISTORICAL NOTE is also at the end of amendments to sections published in the Louisiana Register.

     The LR cites are in the form "LR Vol:Page (Month Year)".  In the example "LR 16:342 (February 1992)", the number 16 is the volume number, 342 is the page number, and February 1992 is the month and year of the notice.  The Louisiana Register is published the 20th of each month, regardless of the day of the week.  In the example above, the Register was published February 20, 1992.  The Louisiana state effective date of an amendment to a section is assumed to be the date published in the Louisiana Register unless an effective date is given in the amendment.  

     In most sections of the Louisiana regulations in this web site the LR cites listed are only for regulations and amendments that EPA has partially or fully approved as part of the Louisiana SIP.  In other words, only the LR cites of the SIP-approved Louisiana regulations are included in this compilation.  Also, there are many places where EPA approved only part of the text amended in the LR cite.  In this compilation, a LR cite does NOT mean that all of the section or amendments to the section approved in a LR cite were also approved by EPA.  EPA may have approved only part of the amendments approved in the LR cite. 

     In about 1990, the Louisiana Air Quality Division began assigning AQ, MM, or OS log numbers to promulgations of and amendments to Louisiana Air Quality Control regulations.  The AQ numbers are for revisions to the regulations whereas the MM and OS numbers are for miscellaneous corrections and administrative changes to the regulations. The first log numbers found in the Louisiana Register are for AQ12 published in the NOTICE OF INTENT section of the November 20, 1990 Louisiana Register on page LR 16:986 for proposed amendments to LAC 33:III, Chapters 51 and 65; and for AQ16 on page LR 16:989 for proposed amendments to Chapter 31; and in the December 20, 1990 (LR 16:1084) issue for AQ20 for proposed amendments to Chapter 33.  The log numbers appeared at the end of the first introductory paragraph. The log numbers eventually began appearing in the titles of the final RULES and the proposed NOTICES OF INTENT sections of the Louisiana Registers for amendments to the Louisiana air quality rules.  Most Louisiana rule-making submittals to EPA in documents have bookmarks which identify the respective AQ, MM, and OS log numbers of the amendments.  The log numbers are indicated in the documentation of most of the Louisiana rule amendments in this web site approved by EPA since July 5, 2011 (76 FR 38977) (LAd34) to help identify the respective amendments approved by EPA. 

Most amendments to the Louisiana SIP-Approved rules in this web site approved by EPA since July 5, 2011 (76 FR 38977)  (LAd34) are documented in a format similar to this example:

“AQ149  §2145.F.4;LAd34;LA021.05;AQ149;LR24:0025(1/20/1998)”


“AQ149” is a Louisiana Department of Environmental Quality (LDEQ) tracking number that usually appears in the header of LDEQ rules being revised in the Louisiana Register.  The number may also start with OS or MM which are for administrative revisions.

§2145.F.4:  §2145 is the section of LAC 33:III and “F.4” is the paragraph or range of consecutive paragraphs revised.

LAd34 is a number assigned by EPA Region 6 for EPA approval of Louisiana SIP Revisions.  See the Louisiana SIP History document in this Region 6 SIP Regulations web site for information about the LAc and LAd numbers and for a complete list of revisions to the Louisiana SIP regulations.

LA021.05: “LA021.” is a number EPA Region 6 assigns to dockets.  “05” is a shortcut document ID -- in most cases, the “05” will be the same as the last two digits of the document ID.  In this case LA021.05 is a shortcut for document  EPA-R06-OAR-2007-0924-0005.

The second "AQ149" is the same as the AQ number at the beginning of the line.

"LR24:0025" is the Louisiana Register volume and page number where the revision is amended in the Louisiana Register.  The Louisiana Register page number is the first page of the RULE section or the page where the text of the amendments to the section begins.

"(1/20/1998)" is the date published in the Louisiana Register and is the Louisiana effective date of the rule revision.

     To see the text of §2145.F.4 submitted to EPA as a SIP revision, go to, open docket EPA-R06-OAR-2007-0924 [usually found under the Section title in this web site], open document EPA-R06-OAR-2007-0924-0005, in the bookmarks click on AQ149 [in this case you have to click on the second AQ149 (01/1998) -- the first AQ149 is a correction to the first AQ149] and go to the Louisiana Register.