<unk><unk>  guidelines for operating<unk>  are determined by the American Society of Heating, Refrigerating and<unk> -Conditioning Engineers (ASHRAE) using a standard known as Minimum Efficiency Reporting Value (MERV). MERV is determined based on the size of particles successfully removed from the<unk>  and is used to classify the efficiency of HEPA filters. Ratings range from 1-16 and efficiency increases as the rating increases. ASHRAE groups surgeries into three categories: minor surgical procedures (A); minor or major surgical procedures performed with minor sedation (B); and major surgical procedures performed with general anesthesia or regional block anesthesia (C). Each surgical category is given a minimum MERV rating it must comply with.
Air filtration in operating rooms
Table of modes of mechanical ventilation
Powered air-purifying respirator
Machine perfusion
Nomenclature of mechanical ventilation
Operating room management
Open-source ventilator
Control of ventilation