The Small Business Administration (SBA) website is helpful in identifying potential vendors or suppliers of products or services. It also identifies those small business firms certified by the SBA as "Disadvantaged" or "HUBZone." All other small business classifications, such as Women-owned or Veteran-owned, only require a prospective vendor or supplier to identify the business as falling under that classification.
The NAICS Code Search portion of the U.S. Census Bureau website provides helpful information about the North American Industry Classification System (NAICS). In order to determine the "size" of a vendor or supplier (e.g., "large" or "small"), the commodity or service being offered must be identified by an NAICS code. Business size varies from one NAICS code to another. Hazardous Waste Treatment and Disposal falls under NAICS code 562211.