Chapter 6: Maintaining Your Filtered Enclosure
3.
4.The weight of the carbon filter with the gasket down will compress the gasket.
Calculating Odor Control Carbon
Filter Life
Labconco developed a modeling program to estimate the filter life for typical carbon filters. Since filter life is dependent on the chemical used, the airflow, filter size, and the dwell time, refer to the Chemical Guide for the Paramount® Filtered Enclosure. The estimated life for Odor Control carbon filters for the filtered enclosures is conservatively calculated at 50% or half of the published values for the Paramount in the Chemical Guide. For example, if you use isopropyl alcohol to disinfect and use approximately 100 ml per week during 2 hours of use per day then follow these steps to calculate the concentration in parts per million (ppm).
Steps for Calculating PPM and Filter Life
1.Determine the amount of the proposed chemical lost to evaporation over a given amount of time. For example, if you use isopropyl alcohol and lose approximately 100 ml per week during 2 hours of use per day.
2.Convert the amount lost into ml/min. For this example:
100 ml X | 1 week X | 10 hours = | 100 ml lost | =.17 ml/min | |
week | 10 hours use | 600 minutes | 600 minutes | ||
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3.Convert ml/min to PPM by multiplying ml/min by the conversion factor found in the second to the last column on the right. For isopropyl alcohol .17 x 41 = 7.0 PPM.
4.Find the PPM value on the chart that comes closest to the value you just calculated in step #3. In this example, round up to 10 PPM, which is close to the calculated 7.0. We may approximate the filter life to be around 155 hours of actual use, but use 50% of this for the Odor Control filters or 78 hours.
5.Insert the estimated filter life into the estimated usage to determine how long filters will last.
78 hours filter life | =7.8 weeks before filter saturation | |
10 hours per week use | ||
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