(a)  For the purpose of this Rule the following definitions shall apply:

(1)           "Functionally dependent" means that structures, buildings or equipment are interconnected through common process streams, supply lines, flues, or stacks.

(2)           "Indirect heat exchanger" means any equipment used for the alteration of the temperature of one fluid by the use of another fluid in which the two fluids are separated by an impervious surface such that there is no mixing of the two fluids.

(3)           "Plant site" means any single or collection of structures, buildings, facilities, equipment, installations, or operations which:

(A)          are located on one or more adjacent properties;

(B)          are under common legal control; and

(C)          are functionally dependent in their operations.

(b)  The definition contained in Subparagraph (a)(3) of this Rule does not affect the calculation of the allowable emission rate of any indirect heat exchanger permitted prior to April 1, 1999.

(c)  Emissions of particulate matter from the combustion of wood shall not exceed:


Allowable Emission Limit

Maximum Heat Input In                                                                   For Particulate Matter

Million Btu/Hour                                                                                 In Lb/Million Btu


Up to and Including 10                                                                                      0.70

100                                                                                                                         0.41

1,000                                                                                                                      0.25

10,000 and Greater                                                                                             0.15


For a heat input between any two consecutive heat inputs stated in the preceding table, the allowable emissions of particulate matter shall be calculated by the equation E = 1.1698 (Q to the -0.2230 power.)  E = allowable emission limit for particulate matter in lb/million Btu. Q = Maximum heat input in million Btu/hour.

(d)  This Rule applies to installations in which wood is burned for the primary purpose of producing heat or power by indirect heat transfer.

(e)  For the purpose of this Rule, the heat content of wood shall be 8,000 Btu per pound (dry-weight basis). The total of maximum heat inputs of all wood burning indirect heat exchangers at a plant site in operation, under construction, or with a permit shall be used to determine the allowable emission limit of a wood burning indirect heat exchanger. Wood burning indirect heat exchangers constructed or permitted after February 1, 1983, shall not change the allowable emission limit of any wood burning indirect heat exchanger whose allowable emission limit has previously been set.

(f)  The emission limit for fuel burning equipment that burns both wood and other fuels in combination or for wood and other fuel burning equipment that is operated such that emissions are measured on a combination basis shall be calculated by the procedure described in Paragraph (f) of Rule .0503 of this Section.


History Note:        Authority G.S. 143-215.3(a)(1); 143-215.107(a)(5);

Eff. February 1, 1976;

Amended Eff. August 1, 2002; April 1, 1999; June 1, 1985; February 1, 1983.