View Sources Source(s) or Contributor(s) Pacific Northwest National Laboratory Measure Guideline: Combustion Safety for Natural Draft Appliances Using Indoor Air Level 4 of the Combustion Safety module, which focuses on: Understand the remediation options available for making home combustion safe for indoor air appliances Attachment(s) Combustion Safety Module Level 4 - Lecture Notes _ Problem Sets.docx Lecture Length 1 hour Last Updated Date 2022-05-25