you know i mean fireplaces their great but you can get you know one hundred percent clean burning natural gas in your fireplaces and i mean you know most of the fireplaces are for ambience anyway they're not that efficient
A lot of fireplaces are just for display, and they are inefficient.
If the RWC is &lt;25% effluent the concentrations may  (1) 4 times the RWC, (2) 2 times the RWC, (3) RWC, (4) RWC/2, and (5) RWC/4.