WPM ( Wooden Packaging Material ) Fumigation
Inspection of fumigation site: Intact floor without cracks or drains Floor not undulated, no pebbles or stones Locate in a safe working area. Well ventilated, sheltered area, rain and wind protected as for as possible.
Stacked to allow good circulation leaving enough space around (2 m).Impervious wrapping removed or slashed. Commodity not impervious to fumigant Not forbidden commodity. Preparation and installation of equipment Vaporizer filled with water and heating . sheets of correct size & specification, Gas distribution line installed, Gas sampling tubes installed (minimum of 3 per enclosure &1 per container).Fan installed and working checked (one in each container and 2 per enclosure ) Cover the enclosure with sheet and make gas-tight sealing at the ground with two rows of sand snakes. Measure enclosure volume and calculate dosage, Establish and mark out hazardous area and place dangerous sings. Preparation to gas enclosure & Application of gas to enclosure Ensure risk area and surrounds free of un protected personnel (up to 3 m).Turn on fans, Test leak checker for working ,Wear and test the respirator for correct fitness. Position calculate gas cans and connect to inlet of vaporizer and the out lat to gas distribution line. Release gas and test fittings for gas leak and correct if necessary. Check vaporizer water boiling, Release required quantity of gas from the cylinder or dispenser, Check for hot gassing, Check for gas leakages around enclosure and correct leakages if any. Initial monitoring Turn off fan after 30 min. Measure gas levels on all monitor lines . Check to ensure all readings are above standard , calculate if equilibrium achieved Turn-on fans, if necessary repeat until equilibrium achieved Ensure levels still above standard-record and document. End point monitoring Measure gas levels on all monitor lines check to ensure all levels above standard Carry out “top-up” procedures , if appropriate Declare fumigation successful or failed, as appropriate-document. De-gassings Ensure risk area and surrounds free of un protected personnel (up to 3 m )Turn-on fans Wear gas mask and test for fitness Open enclosure and allow ventilation. Test for Thresh hold limit value (TLV)-Continue aeration until gas level below TLV . Remove warning signs and risk area demarcation . Documentation Complete all documentation and release fumigated goods after ensuring gas-free.
