Enclosures 2 m high and up to 12 m square covered with light-weight cotton-polyester netting were treated with either Deet, diisopentyl malate (DPM) or Indalone to determine if the biting midges, Culicoides mississippiensis, C. furens, C. barbosai and C. floridensis, attracted by CO2 or human bait within the enclosures could be prevented from entering the area. The studies indicated that Deet and DPM treatments provided good area protection to people for 4 and 5 days, respectively, while Indalone in one test was somewhat erratic in its effectiveness. The residual effectiveness of the DPM treatment was greater than the Deet treatment after exposure to rain.