Fumigation is the process in which toxic fumes has been used at a lethal concentration in an enclosed space for a period of time to keep the pest population under control below the economic threshold level. Fumigation is the process in which a fumigant is introduced into a gas-tight enclosure at a particular temperature and pressure can exist in a gaseous state in sufficient concentration and for sufficient time to be lethal to insects and other pests. Govt. of India permits only two fumigants that can be used for fumigation purposes i.e. Aluminium Phosphide and Methyl Bromide, MBR is generally used for export treatment only.
- Phosphine: Phosphine is one of the most toxic fumigants to stored product insects in general. Phosphine uptake in insects is slow and progressive and it is not greatly influenced by the increase in concentration. It’s required sufficient concentration & temperature and a minimum exposure period.
- Methyl Bromide: It is used as a soil and post-harvest commodity fumigant to control insects, weeds and soil pathogens. It is colour-less, odour-less and nonflammable. It is especially suitable for vacuum fumigation and plays an important role in quarantine purposes. It does not penetrate readily at normal atmospheric pressure, into tightly packed commodities. It is most sorbed comparatively by the commodities than phosphine. Fumigation with Methyl bromide should be avoided on seeds meant for planting or malting & can foods.
- Inform warehouse in charge before undertaking fumigation
- Place danger placards and assemble safety equipment prior to taking up fumigation
- Ensure that the stack is duly prepared for fumigation providing adequate space around the stack to facilitate proper sealing.
- Ensure that all unauthorized personnel are clear of the warehouse before placing fumigant.
- Calculate the required phosphine dosage and ensure the product is on hand.
- Assemble safety equipment and monitoring equipment for supervision job.
- Provide lock and keys for the fenced-in area to be used for Wet De-activation.
- Display Danger placards together with a list of names and phone nos. of personnel to be contacted in case of emergency.
- Check fumigation cover for leaks and carry out repairs, if necessary.
- Contact lenses should not be worn by anyone using a mask, irreparable damage to the eye may occur if the mask leaks and the gas gets in between the lenses and the cornea.
- Facial hair such as beards and sideburns interfere with the proper sealing of the face mask. Do not allow such persons to participate as a matter of procedure.
- Never fumigate alone.
- No persons to be allowed into the warehouses other than personnel carrying out fumigation.