DPH presents clarifications to Health Code Article 38 and updates Air Pollutant Exposure Zone

The San Francisco Department of Public Health presented proposed rules and regulations clarifying Health Code Article 38, which requires enhanced ventilation standards for new and significantly renovated "sensitive use" buildings located in the city’s Air Pollutant Exposure Zone (APES).

Jonathan Piakas of the Environmental Health Branch said Article 38 requires an enhanced ventilation system that "sufficiently removes harmful, fine particles from the air and prevents them from going from outside and reaching our sensitive use populations inside these new buildings," and that the system is designed around MERV‑13‑equivalent filtration and use of positive pressure where appropriate. He reviewed the law’s history: the ordinance originated in 2008, was amended in 2014 to expand covered sensitive uses (child care, schools, adult day care, licensed health facilities) and to remove a 10‑unit threshold so small projects near high‑pollution corridors are covered.

Piakas described the five‑year update cycle for the APES and said the 2020 map expanded in part because state emission factors became more restrictive and because the modeling for the update included stationary and maritime sources for the first time. To simplify compliance, the department partnered with state and regional air agencies to model the city and publish the APES; a Planning Department map layer now lets users check a parcel for APES inclusion.

The rules and regulations under review clarify who may design and certify enhanced systems, set performance and maintenance expectations, and add disclosure requirements so systems remain protective over time. Piakas said the department is in the middle of a 30‑day voluntary public‑comment period and had not yet received additional comments on the draft rules.

Commissioners asked about updating APES in the face of long‑term emissions reductions and climate‑related changes; Piakas said the map is updated at least every five years and staff coordinate with the California Air Resources Board and the Bay Area Air Quality Management District to account for new information. Commissioners also discussed using approved enhanced‑ventilation buildings as clean‑air respite sites during wildfire events; Piakas said department teams have used approved sites and shared data across divisions to identify suitable locations.