@article{keever_1999, title={Modified tobacco warehouse aerations for lowered acute emissions of phosphine into surrounding environs}, volume={34}, ISSN={["0749-8004"]}, DOI={10.18474/0749-8004-34.4.452}, abstractNote={Regulations of atmospheric emissions of phosphine have been enacted by a number of states in the U.S. The maximum concentration allowed at the property of fumigated sites addresses not environmental contamination, but rather the health and safety of citizens in the proximity of warehouse fumigations. In a warehouse fumigation, phosphine is most rapidly vented just after opening the warehouse for aeration. Therefore, alternative aeration techniques were tested with the objective of minimizing peak concentrations outside the warehouse through a slower and more uniform emission rate. Three types of warehouse aerations were tested: (1) a standard aeration with all doors and vents open for 3 d, (2) a modified aeration with only roof vents open for 1 d and then all doors and vents open for the following 2 d, and (3) a second modified aeration with only one large door open for 1 d and then all doors and vents open for the following 2 d. Rates of phosphine emission from the warehouses throughout aeration, gas concentrations downwind from the warehouse, and the adequacy of aeration in both the commodity and warehouse freespace were determined. Modified aerations greatly reduced phosphine peak emission rates, adequately aerated the warehouse freespace, and for most application situations, adequately aerated the tobacco. At one warehouse complex, the three types of aeration (Standard, Roof-Vent-Only and Door-Only) released 45.7, 8.5 and 9.7%, respectively, of the available gas during the first 30 min of aeration. Compared with the Standard aeration, both types of modified aeration delayed aeration of both freespace and tobacco by less than 24 h. Outside downwind concentrations of phosphine were greatly reduced by the modified aerations, especially the Roof-Vent-Only in which downwind concentrations were virtually undetectable.}, number={4}, journal={JOURNAL OF ENTOMOLOGICAL SCIENCE}, author={Keever, DW}, year={1999}, month={Oct}, pages={452–461} }
 @article{keever_hamm_1996, title={Descriptive model of phosphine concentrations and emission rates during controlled aeration of fumigated tobacco warehouses}, volume={31}, ISSN={["0749-8004"]}, DOI={10.18474/0749-8004-31.2.218}, abstractNote={A model was developed to describe the emission of phosphine gas from the interior of a tobacco warehouse to the outside during controlled aeration after fumigation of the warehouse. We used a fan/stack exhaust system to control the aeration, but other systems can be used. Model inputs include phosphine concentrations in the warehouse just prior to aeration, warehouse characteristics, and characteristics of the system used to release phosphine. Model outputs for any time during aeration include the emission rate of phosphine from the warehouse, the phosphine concentration remaining in the warehouse, and suggested exhaust rates that help fumigators comply with regulatory standards on phosphine emission rates. (Exhaust rate refers to release of air/phosphine mixture from the warehouse [=volume/time], but phosphine emission rate refers to the amount of phosphine [=mass/time]). The model also calculates how much exhaust rates can be increased at regular time intervals to hasten aeration without exceeding the initial phosphine emission rate. The model can be used by fumigators to comply with regulatory standards on phosphine emissions, and by regulators to assess that compliance. Diffusion of phosphine from the packaged tobacco (cases) into the freespace of the warehouse and its impact on the model are discussed.}, number={2}, journal={JOURNAL OF ENTOMOLOGICAL SCIENCE}, author={Keever, DW and Hamm, LA}, year={1996}, month={Apr}, pages={218–226} }
 @article{keever_bradley_ganyard_1977, title={EFFECTS OF DIFLUBENZURON (DIMILIN) ON SELECTED BENEFICIAL ARTHROPODS IN COTTON FIELDS}, volume={6}, ISSN={["0046-225X"]}, DOI={10.1093/ee/6.5.732}, abstractNote={Populations of the arthropod predators, Geocoris punctipes (Say), Nabis spp., Hippodamia convergens Guerin, Coleomegilla maculata (DeGeer), Orius insidiosus (Say), Chrysopa spp., and Araneida, were monitored in cotton fields treated with diflubenzuron, in cotton fields treated with conventional insecticides, and in cotton fields to which no insecticides were applied. G. punctipes and H. convergens were taken from both diflubenzuron-treated and untreated fields to the laboratory to study oviposition and egg hatch. With the exception of G. punctipes , reduction of predator populations in diflubenzuron-treated fields vs. untreated fields was not significant. This was in marked contrast to the highly adverse effects of conventional insecticides upon the predator populations. For 6 days after collection, egg hatch in laboratory-held H. convergens was significantly lower in females collected from diflubenzuron-treated cotton fields than in those from untreated fields. Additional differences in fecundity were not detected in the laboratory studies.}, number={5}, journal={ENVIRONMENTAL ENTOMOLOGY}, author={KEEVER, DW and BRADLEY, JR and GANYARD, MC}, year={1977}, pages={732–736} }