I am not sure what it is about fresh air intake for exhaust ventilation systems, but we should call them “Rodney”, as in Rodney Dangerfield, because they get no respect. As I said in 2016 and 2018 in my articles:
- The Ventilation Design Basis begins with our intakes
- FRESH AIR intakes for a ventilation system need to be from a source of FRESH AIR!
Here are two (2) photos of a person bragging on their NH3 refrigeration start-up. Besides the fact that the process does not appear to have completed its PSSR, take a look at the piping work and its location and proximity to the fresh air intake…
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401.4 Intake opening location. Air intake openings shall comply with all of the following:
- Intake openings shall be located not less than 10 feet (3048 mm) from lot lines or buildings on the same lot.
- Mechanical and gravity outdoor air intake openings shall be located NOT LESS THAN 10 FEET (3048 mm) horizontally from ANY HAZARDOUS OR NOXIOUS CONTAMINANT SOURCE, such as vents, streets, alleys, parking lots and loading docks, except as specified in Item 3 or Section 501.3.1. Outdoor air intake openings shall be permitted to be located less than 10 feet (3048 mm) horizontally from streets, alleys, parking lots and loading docks provided that the openings are located NOT LESS THAN 25 FEET (7620 mm) vertically above such locations. Where openings front on a street or public way, the distance shall be measured from the closest edge of the street or public way.
- Intake openings shall be located NOT LESS THAN 3 FEET (914 mm) BELOW contaminant sources where such sources are located within 10 feet (3048 mm) of the opening.
- Intake openings on structures in flood hazard areas shall be at or above the elevation required by Section 1612 of the International Building Code for utilities and attendant equipment.