Ozone vacuum-ultraviolet (VUV) ozone generators, employ a light source that generates a narrow-band ultraviolet light, a subset of that produced by the Sun. The Sun's UV sustains the ozone layer in the stratosphere of Earth. UV ozone generators use ambient air for ozone production, no air prep systems are used (air dryer or oxygen concentrator), therefore these generators tend to be less expensive. However UV ozone generators usually produce ozone with a concentration of about 0.5% or lower which limits the potential ozone production rate. Another disadvantage of this method is that it requires the ambient air (oxygen) to be exposed
Burning Like the Midnight Sun the Midnight Sun" has received some of the most positive reviews of any album in the band's career. Jeff Eibel, writing for the Spin Control column in the "Chicago Sun-Times", called The Choir's latest release "a late-career triumph," and remarked that "Midnight Sun" was the band's "second exceptional album in a row, and its best since 1990's landmark "Circle Slide"." "Christianity Today"′s Andrew Greer highlighted the band's ability to create "smooth musical clarity to contrast the murky exploration of everyday faith," while "The Phantom Tollbooth"′s Derek Walker called "Midnight Sun" a "sonic delight" and The Choir's "most cohesive, melodic and