Identify which state plumbing licenses require a medical gas endorsement, using specific state examples

Steps

1. Confirm Texas requires a separate Medical Gas Piping Installation Endorsement (Texas State Board of Plumbing Examiners) on top of an existing Master Plumber, Journeyman Plumber, or Plumbing Inspector license; per TSBPE's own eligibility page (tsbpe.texas.gov/license-types/endorsements/), the stated prerequisite to sit the endorsement exam is completion of a 24-hour training course approved by the TSBPE, and the exam itself is based on 'ASSE Gold' materials and NFPA 99
2. Do not cite a TSBPE-recognized alternate pathway via demonstrated ASSE 6010 completion in place of the 24-hour approved course — TSBPE's current official eligibility page lists only the approved 24-hour course as the qualifying prerequisite; older secondary sources describing an ASSE-6010 alternate should not be relied on without confirming against tsbpe.texas.gov directly
3. Confirm Washington State requires a Medical Gas Endorsement (WA Department of Labor & Industries) for a Medical Gas Piping Installer (MG01) — per L&I's own page (lni.wa.gov), requiring an active Journey Level Plumber (PL01) certification, at least 32 hours of training in an L&I-approved medical gas course, and proof of an NITC or METC card before applying
4. Confirm Montana also administers a medical gas piping endorsement (Montana Board of Plumbers) requiring proof of an approved training program based on NFPA 99C and ASME Section IX that meets ASSE Series 6000 professional-qualification-standard criteria, with third-party testing acceptable to the board
5. Confirm licensing requirements and any qualifying pathways for the specific state relevant to the project directly on that state's official licensing-board site rather than assuming any one state's rule (or alternate pathway) generalizes to another, since medical gas endorsement requirements are state-specific and can change