The initial request for certification or renewal application shall be signed by the employer and shall contain the name of the firm, its mailing address, the physical location of the firm's principal place of business and a description of the business operations and items produced. In addition, the initial or renewal application shall contain the names, addresses, and languages (if other than English) spoken by the homeworkers that are currently employed (if any) or expected to be employed. The employer shall also provide the Administrator, within thirty (30) days, a notice of each change of address of the principal place of business. The notification shall be in writing and addressed to the Administrator, Wage and Hour Division, Employment Standards Administration, 200 Constitution Avenue, NW., Washington, DC 20210.