Choose the chemical(s) and the respective use concentration(s) that you will be dealing with from the pull-down menu.

Contaminant Concentration: This is the highest concentration of contaminant expected in the workplace. Enter the concentration of chemical in ppm or mg/m3.

If the chemical is not on the pull-down menu, contact MSA Customer Service at 1-800-MSA-2222 for additional information.

If the chemical chosen has an applicable OSHA standard, a Breakthrough Time will not be calculated on this website. OSHA standards can be found at: http://www.osha.gov