One study concluded that it is important to achieve and maintain temperatures of above 118.4°F (48°C) for more than 20 min to effectively kill all life stages of bedbugs, considering the clutter in treated spaces and the fact that bedbugs move to cooler temperatures, treatment times must be much longer to penetrate cracks and crevices, At 60-min exposure to 113°F , approximately 50% of adult bedbugs exposed survived, while 20% survived after 4 hours. Complete mortality was obtained at temperatures 118.4°F, 122°F, and 131°F for all exposure times except 10- min at 118.4°F. Even if some nymphs emerged, they did not develop at temperatures higher than 118.4°F. No differences in mortality were shown between fed and unfed bedbugs.
90% higher temperatures than previously reported were required to kill bedbugs when the temperature rose slowly — possibly because of the way previous heat tests have been conducted — but it is not known what enables bedbugs to resist gradual heat stress.<ref>[http://www.propanecouncil.org/uploadedFiles/Council/Research_and_Development/REP_12221%20Efficacy%20of%20Heat%20on%20Bed%20Bugs.pdf Fundamental Research on the Efficacy of Heat on Bed Bugs and Heat Transfer in Mattresses''], TEMP-AIR, INC</ref>. The EPA will also soon be offering $550,000 in grants to state and tribal agencies for pilot projects relating to outreach and education. <ref>[http://bedbugger.com/2010/06/11/bed-bugs-cheer-ohios-propoxur-exemption-request-denied/ ''Bed bugs cheer: Ohio’s propoxur exemption request denied'']</ref>
==Environmentalism==