I am curious about the opinions/experiences of others on schedules for equipment replacement such as hose, filters, and masks. Equipment suppliers ( in my case Lambert's health care in Knoxville, TN) give time periods for replacement with no explanation. Are these replacement periods for our benefit...

About a week ago my equipment supplier printed the charts for my machine. ( A Resmed S9). Where is a reference that can explain the
charts as to the meanings and interpretations for the charts??

Thanks H. Hampton.