Abstract
Plywood pieces (1×5×0.3cm) were contaminated artificially with 104.5 of Escherichia coli or 104.7 of Staphylococcus aureus per piece. Also, the pieces and plywood boards (60×90×0.3cm) were placed in the floor of a chicken house during 1 week to contaminate naturally. A number of 107.3 of bacteria contaminated per piece or of 106.5 per 1 cm2 in the board.
The pieces were placed in a wooden box (1 m3 of capacity) and the boards in a room (14.5 m3 capacity). A volume of 40 ml of formalin per m3 of the capacity were sprayed like a mist. A high degree of disinfection was obtained as well as the fumiga-tion using the same volume of formalin.
