The United States Small Business Administration (SBA) is increasing small business size standards for 209 industries in North American Industry Classification System (NAICS) Sector 31-33, Manufacturing. SBA is also modifying the size standard for NAICS 324110, Petroleum Refiners, by increasing the refining capacity component of the size standard to 200,000 barrels per calendar day for businesses that are primarily engaged in petroleum refining and by eliminating the requirement that 90 percent of the output to be delivered be refined by the successful bidder from either crude oil or bona fide feedstocks. The Agency is also updating Footnote 5 to NAICS 326211 to reflect the current Census Product Classification Codes 3262111 and 3262113. As part of its ongoing comprehensive size standards review, SBA evaluated employee based size standards for all 364 industries in NAICS Sector 31-33 to determine whether they should be retained or revised. This rule is one of a series of rules that result from SBA's review of size standards of industries grouped by NAICS Sector.