There are many misconceptions about when the right time to test fluid may be. Many people test their fluid when they suspect that there may be a problem. At this point it is usually too late. Another common mistake is “spot checking” which is usually once a year or at random intervals. The best program to institute is regularly scheduled or “Trendline” analysis. The interval then will be determined by the sensitivity of the equipment and the severity of their function to the system. Also to take into consideration would be the number of hours of operation and environment that the equipment is in.