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</o:shapelayout></xml><![endif]--></head><body lang=EN-CA link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Dear Alex<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>I am wary of ever disagreeing with anything you contribute so I am listening carefully:<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><div><div><p class=MsoNormal><b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>></span></b>However, I don't feel that the very recent (shall I singular example) Mongolian experience of very excellent combustion of processed coal used in heating stoves ....negates concerns about real world combustion of many less processed fuels used in chimneyless cooking stoves. <span style='color:#1F497D'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>That raises a very interesting question: why is there not a heck of a lot more effort being put into installing chimneys and hoods? It is what some call blindingly obvious. No one burns their space heating fireplace inside the room any more. In the White Tower in London, on the top floor. There is a large banquet hall. Fires were lit against a wall on a very shallow alcove and has a chimney that starts close to the ceiling. Between the fire and the chimney/vent there is a shallow curve like half a channel built into the wall. So since 1078 AD we have known that putting in a chimney gets the smoke out of the room.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>There is a possibility that the Romans and Greeks also knew about chimneys. And the Egyptians. So why doesn’t the improved stove and IAQ community apply what has been around for millennia?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal>How many orders of magnitude worse (combustion) is the best mass produced raw wood chimneyless cook stove? <span style='color:#1F497D'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Three. Three point three if you understand dB.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal>It may not <span style='color:#1F497D'>[be] </span>strictly correct <span style='color:#1F497D'>[to] </span>criticize a fuel for incomplete combustion but if there isn't a real world example of excellent combustion with a given fuel used for a given purpose then I don't have a huge problem with<span style='color:#1F497D'> </span>being critical of fuels. <o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>There is a power station in the UK that burns car tires. I would say there is no fuel that cannot be burned cleanly. On a small scale it may be unproven, but we should get over the issue of problem identification. For the WHO to say that combustion products are inherent emissions is obviously misleading. It is like the guy who wrote that the “combustion efficiency of dung is 85%”. That’s silly. Dung doesn’t combust itself (unless it is in a gigantic pile). Stoves combust dung and have a combustion efficiency. A crappy stove can’t burn crap.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal>Best in class can still be a loser.<o:p></o:p></p></div></div><div><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Best in class that is not good enough is still not good enough. If the stove designers are so clever, let them design better stoves. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Thanks<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Crispin<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p></div></div></body></html>