The Costco Gas Station hours are usually longer than the Costco Warehouse opening hours, so make sure that you are viewing the Costco Gas Station hours, and not the Store Hours, if you search through an app or with google maps.
All dental hygienists in the United States must be licensed by the state in which they practice, after completing a minimum of two years of school and passing a written board as well as a clinical board exam. State requirements vary by state, and are controlled by state dental boards.
Dental hygienists are licensed by the state or province in which they plan to practice. Generally, candidates for licensure must be graduates of an accredited dental hygiene program, must pass the National Board Dental Hygiene Examination taken near graduation and must pass a state or regional clinical examination.