Our project is outside the U.S. and MERV filters are not available. We want to run the HVAC system during construction – what should we do?

In countries where filters with MERV ratings are not available, filtration media must be Class F5 or higher, as defined by CEN Standard EN 779–2002. Filtration media with a minimum dust spot efficiency of 30% or higher and greater than 90% arrestance on a particle size of 3–10 μg are also acceptable.