Assessee claimed depreciation on pollution control equipment. AO held that description of assets as stated by assessee did not fall in category of 100% depreciation, therefore, AO allowed only 15% depreciation on Plant & Machinery as applicable to general Plant & Machinery and made disallowance. DRP confirmed disallowance on reason that assessee did not prove that pollution control equipment was required for purpose of business and such equipment was used in controlling pollution-emanating from manufacturing operations of tax payer.  Tribunal held that, the assessee had purchased Plant & Machinery which was categorized by him as pollution control equipment. What sort of evidence was required to establish that these were used in controlling pollution was not specified by DRP. Use of machinery in business had not been doubted even by AO as he allowed depreciation at 15%. Assessee categorized certain equipment as pollution control equipment, nature of equipment was to be examined in context of business operations of assessee, the aspect of the assessee had not correctly appreciated by AO or DRP, therefore issue  was set as side for re-examination of nature of equipment purchased and its utilization in business. (AY. 2008 -09 to 2011-12)