{"operation":"document","citation":"Mich. Admin. Code R 460.20303","title":"Vault and pit sealing, venting, and ventilation","source_type":"regulation","agency":"Michigan Public Service Commission","status":"current","official":true,"published_on":null,"effective_on":"2026-05-04","summary":"Rule 303. In addition to the requirements contained in 49 C.F.R.§192.187(a)(3), which is adopted by reference in R 460.20606, an operator shall ensure that the outside end of the ventilation ducts of an underground vault or closed top pit is equipped with a suitable weatherproof fitting or vent head","machine_formats":{"json":"https://regulus.evalyn.ai/document/mi-admin-code-r-460-20303.json","markdown":"https://regulus.evalyn.ai/document/mi-admin-code-r-460-20303.md"},"app_url":"https://regulus.evalyn.ai/document/mi-admin-code-r-460-20303","source_url":"https://ars.apps.lara.state.mi.us/AdminCode/DownloadAdminCodeFile?FileName=R%20460.20101%20to%20R%20460.20606.pdf","body":"Rule 303. In addition to the requirements contained in 49 C.F.R.§192.187(a)(3), which is adopted by reference in R 460.20606, an operator shall ensure that the outside end of the ventilation ducts of an underground vault or closed top pit is equipped with a suitable weatherproof fitting or vent head designed to prevent foreign matter from entering or obstructing the duct.\n\nHistory: 1998-2000 AACS.","truncated":false,"body_characters":400}