Abstract Two series of bioassay tests were conducted by exposing a total of 7; pest species in commercial transport trailers with volumes of 33 to 71 m . In the first series of tests, conducted in Miami, Florida, 5 species of colony-reared insects and 1 species of ticks were exposed. Approximately 100 resistant (Gainesville, multiple resistant) M. domestica, 50 resistant (Hazard) B. qermanica, 20 H. virescens, 50 A. grandis, and 50 R.sanquineus adults were, excepting A. taeniorhynchus (tested without replication), included in each of 3 test replications. In test series 2, conducted in Baltimore, Maryland, approximately 30 hazard strain B. germanica, 12 B. orientalis (males only) and 100 P. japonica were used in each test replication. Japanese beetles were field collected in methyl eugenol baited traps and caged in 83 mm diara x 60 mm deep, 3 mm mesh wire screen cages; all other species were caged in 0.24 L (1/2 pint - same dimensions as Japanese beetle cage) paper cans with tops replaced with tulle, nylon mesh screen (7 mesh/mm2). Candidate compounds were formulated as aerosols and dusts. Aerosols were formulated with technical grade material in a 1:1 mixture of Freons 11 and 12. The standard material for aerosol treatments, Sumithrin, was also formulated in an aqueous, CO^-propelled system by Enviro-Spray Systems, Inc. Dusts were formulated with HiSii 233 as the carrier. Sumithrin was also formulated with diatomaceous earth (Diabrite K-8, from international Diatoms Industries, Ltd). Cages were placed on the floor of the test trailer ca 10 cam from side walls. Dusts were applied with a “gun” employing compressed CO2 as the propellant, through the rear trailer door. Aerosols were applied from within by an operator walking the length of the trailer while releasing formulation for slightly less than the calculated time to obtain desired dosage and then weighing and adjusting with additional material. Following treatment, trailers were closed for 10 minutes. Then the right rear door was opened and test insects removed 20 min later. Japanese beetles were held for 72 hr before mortality counts were made; all others were counted at 24 hr after treatment. Average temperature during treatment and holding of the first test series was 21°C, and relative humidity was 81 ± 13%. In the second series temperatures averaged 23°C and relative humidity was 72%. Abbott’s formula was used to adjust for control mortality.