Allowing a credit against the State income tax for 20% of the costs of equipment placed in service during the taxable year to be used in connection with transient mass-emission repair or testing; allowing unused tax credits to be carried forward for 5 taxable years; applying the Act to tax years after 1997 for equipment placed in service after 1997; and requiring the Department of the Environment to prepare and publish a list of equipment that complies with the requirements of the tax credit on or before December 31, 1999.