permissible concentration limit for CO
maximum permissible concentration
maximum permissible concentration of unidentified radionuclides
maximum permissible concentration value
maximum permissible limit
permissible concentration
permissible limit for a regression line
permissible limit of vibration
environmental limit concentration
explosion concentration limit
explosive concentration limit
firing concentration limit
hazard concentration limit
the limit concentration of pollutants
High-concentration and low-concentration wastewater