The term “fumigants” is correctly used when describing gases which are used to control pests. Many people call any pest control product a fumigant or the pest control process a fumigation. Regular pest control service is not fumigation.
Fumigants are used to control pests in fields, post harvest, and in structures. The main difference between regular pest control products and a fumigant is that the fumigant, being a gas, is under pressure in cylinders or is a solid which forms a gas when moisture in the air comes in contact with the solids. Fumigants, or the process of fumigation, can only be done by people specially trained to apply a fumigant. Entering a fumigated area requires the use of a self contained breathing apparatus, similar to what divers use. Also, security must be provided in order to make sure that people do not wander into the fumigated area.
Fumigants are different from space sprays or foggers in that the space sprays and foggers are pressurized but are not gases. These others create liquid droplets which enter the air and settle. Gas fumigants remain in the room until aerated.
State regulatory agencies have specific requirements for the use of fumigants. At the very least, a certified applicator or someone under the direct supervision must be in charge. Homeowners cannot buy fumigants nor can a professional who does not hold the proper license.
Fumigants penetrate all areas of a fumigated area. This allows the fumigant to penetrate to areas where the pests are living; the pests do not have to contact the material by wandering onto it as with a surface treatment. Fumigation is used to control stored product pests, drywood termites, bed bugs, and rodents.
The most common fumigants today are methyl bromide, sulfuryl fluoride, and phosphine. Methyl bromide and sulfuryl fluoride are gases in pressurized containers, and phosphine is in a solid form.
Fumigants must be used very carefully. After the proper time elapses to control the pests, the area is aerated and air readings are taken. Once cleared, people can reenter. There is no residual effect or long term control after aeration.