Clean Rooms Typically have a cleanlines level quantified by the number of particles per cubic meter at the predetermined molecule measure.the ambient outdoor air in a typical for each cubic meter in the measurement ,Equivalent to an ISO 9 Cleanroom ,Whilke by comparison an ISO 1 Cleanroom While by Comparison an ISO 1 Cleanroom permits no particles in that size range and just 12 particles in that size range and just 12 particles for each cubic meter of 0.3 um amd smaller