12.  Accrued Warranty Reserve

The Company provides for the estimated costs of warranties at the time revenue is recognized. The specific terms and conditions of those warranties vary depending upon the product sold, the location of the sale and the length of extended warranties sold. The Company’s product warranties generally start from the delivery date and continue for up to eighteen months. Factors that affect the Company’s warranty obligation include product failure rates, anticipated hours of product operations and costs of repair or replacement in correcting product failures. These factors are estimates that may change based on new information that becomes available each period. Similarly, the Company also accrues the estimated costs related to a specific plan developed by the Company to address reliability repairs on products covered under standard warranty and for products no longer in warranty when, in the Company’s judgment, it is prudent to provide such repairs. The Company assesses the adequacy of recorded warranty liabilities quarterly and makes adjustments to the liability as necessary. When the Company has sufficient evidence that product changes are altering the historical failure occurrence rates, the impact of such changes is taken into account in estimating future warranty liabilities.

Changes in accrued warranty reserve during the six months ended September 30, 2011 are as follows (in thousands):