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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 Nate<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 experimenting with a different form of stability as the chances of a pot tipping over are not as great as that of a pot falling off. If the support triangle or square of a stove is relatively then putting on a large diameter pot is dangerous because it easily falls over spilling hot water on everything and everyone.<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'>We are looking at a rice steaming soblok as the most dangerous local cooking container. It has a hollow space at the bottom where water is boiled continuously, a platform for holding the rice which is more dense than water, and a tall pot with little space above. When tilted the centre of gravity moves more than it would if there was no steamer section.<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'>When that same pot is used for boiling water it is relative tall for its diameter. When tilted the water shifts to the outside moving the CG more than the tilt of a solid object.<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 was thinking of a spec whereby the pot supports should be adequate to cause the water to spill out of an 80% full pot before falling over. It is a test that can be done mathematically as well as practically.<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'>Interested?<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'>Regards<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'>Crispin in Jakarta<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 style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0mm 0mm 0mm'><p class=MsoNormal><b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif"'> Stoves [mailto:stoves-bounces@lists.bioenergylists.org] <b>On Behalf Of </b>Nathan Johnson<br><b>Sent:</b> Monday, September 23, 2013 11:28 PM<br><b>To:</b> <stoves@lists.bioenergylists.org><br><b>Subject:</b> Re: [Stoves] Stoves Digest, Vol 37, Issue 24<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Hi Lanny, <o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>There are two methods and metrics commonly used to measure the susceptibility of a stove from tipping over<o:p></o:p></p></div><div><p class=MsoNormal>1) method -- with a stove standing vertically, tilt the stove to one side until it falls over; metric -- the angle that the stove can be tilted away from vertical before it tips over on its own (typically used for portable stoves)<o:p></o:p></p></div><div><p class=MsoNormal>2) method -- apply a specified horizontal force to the stove; metric -- if the stove tilts, moves, deforms, or falls over when the force is applied (typically used for larger stationary stoves)<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Protocols should not specify the required size of the base to prevent tipping. That decision is left to the designer based on his/her findings from the safety tests. <o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Most protocols do not require pots present on the stove. Yet, as you note, a pot can affect the stove's risk of tipping. No doubt all aspects of the cooking system--stove, user, pots/utensils, kitchen--affect cooking safety. Many people in the stove community tend to consider the larger contexts that influence the efficacy of technical designs. I have a similar viewpoint, and chose to include the stove when developing a new set of safety guidelines tailored to biomass cookstoves. You can find my work on stove safety here <a href="http://community.cleancookstoves.org/user_content/files/003/052/3052100/a8d66ebfa9745553fb1d971160a282d4-bssp1.0.pdf">http://community.cleancookstoves.org/user_content/files/003/052/3052100/a8d66ebfa9745553fb1d971160a282d4-bssp1.0.pdf</a> The text is copied from my Master's Thesis. Let me know if you want a copy of the full text. <o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Best regards, <o:p></o:p></p></div><div><p class=MsoNormal>Nate<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p><div><div><div><div><p class=MsoNormal><span style='font-size:13.5pt;font-family:"Helvetica","sans-serif";color:black'>--<br>Nathan Johnson<br>Assistant Professor<br>Department of Engineering & Computing Systems<br>Arizona State University<br><br></span><o:p></o:p></p></div></div></div></div><p class=MsoNormal><o:p> </o:p></p></div></div></body></html>