About TapeAlert and frequency-based cleaning
Using TapeAlert with frequency-based cleaning ensures that a drive is cleaned at least every x hours, depending on the setting for the cleaning frequency. In addition, the drive can be cleaned sooner if the drive sets the CLEAN_NOW or CLEAN_PERIODIC TapeAlert flag.
When TapeAlert is used without frequency-based cleaning, a drive is cleaned only when the drive sets its CLEAN_NOW or CLEAN_PERIODIC flags.