noise and emissions controls

Hi Cathy, GBCI does not have any published guidance on db levels or on specific emissions control limits that projects must adhere to. The general guidance that GBCI provides is to demonstrate the site maintenance equipment performs better in terms of noise levels and emissions, than standard practice. CARB is a good standard to use as their emissions limits are stricter than EPA recommended emissions limits for site maintenance equipment. Other than this reference, there are a few resources online that point to best practices for site maintenance equipment in terms of db level and emissions standard. For example, the following document has db level requirements listed on page 151. https://www.documents.dgs.ca.gov/green/bpm-bbmbt.pdf I think the intent behind the reviewer comment is to ensure there are set standards the equipment is meeting to ensure it is environmentally preferred. I do not think there is a specific db level or emissions control limit that is required, however, whatever is levels are specified in the plan must be able to demonstrate they produce a lower environmental impact than standard practice. I hope this helps!