Dear all,

We have mechanically ventilated spaces. For the option 1 we therefore have to comply with the requirement B. interior cross-contamination prevention. To create negative pressure we provide exhaust rates of 0.50 cfm per square foot (2.54 l/s per square meter) for all the spaces where hazardous gases or chemicals may be present or used, except in the garage. For the garage we want to implement airlocks with overpressure (The USGBC states that an airlock is a reasonable way to avoid contaminants from the parking areas from migrating into occupied spaces).

To avoid contaminants our strategy is to install airlocks to every staircase core which connect the parking areas with the occupied areas.

Elevators which serve the parking areas with the occupied areas will be equipped with elevator lobbies with self-closing doors and deck-to-deck partitions. Do we have to install airlocks with overpressure in front of the elevator lobbies, do we have to establish elevator lobbies with overpressure or is the ingress of contaminates with an elevator lobby with self-closing doors excluded and we do not need to install airlocks here? What do you think?

Many thanks in advance for your help.