(a) An air curtain incinerator operates by forcefully projecting a curtain of air across an open, integrated combustion chamber (fire box) or open pit or trench (trench burner) in which combustion occurs. For the purpose of this division only, air curtain incinerators include both firebox and trench burner units.(b) Air curtain incinerators that burn only the materials listed in paragraphs (1) through (4) of this subsection are required to meet only the requirements in this section and §§113.2349 through 113.2355 of this title (relating to When must I comply if my air curtain incinerator burns only wood waste, clean lumber, and yard waste?, What must I do if I close my air curtain incinerator that burns only wood waste, clean lumber, and yard waste and then restart it?, What must I do if I plan to permanently close my air curtain incinerator that burns only wood waste, clean lumber, and yard waste and not restart it?, What are the emission limitations for air curtain incinerators that burn only wood waste, clean lumber, and yard waste?, How must I monitor opacity for air curtain incinerators that burn only wood waste, clean lumber, and yard waste?, What are the recordkeeping and reporting requirements for air curtain incinerators that burn only wood waste, clean lumber, and yard waste?, and Am I required to apply for and obtain a Title V operating permit for my air curtain incinerator that burns only wood waste, clean lumber, and yard waste?) and are exempt from all other requirements of this division.(1) 100 percent wood waste.(2) 100 percent clean lumber.(3) 100 percent yard waste.(4) 100 percent mixture of only wood waste, clean lumber, and/or yard waste.