sought due to safety and efficacy concerns. Vaporized hydrogen peroxide is a dry gaseous method that has been used as a reliable alternative for aseptic processing isolators, and more recently, for room/facility decontamination. Hydrogen peroxide and silver in solution and diluted in water is a non-toxic and low cost agent. For example, to fumigate a 1000ft3 (~28.32 m3) area, a 20% solution (200mL of solution in 1000mL demineralized water) would be sprayed via fogger for 30 minutes. Fogging may be done at a rate of up to 130mL/minute and the contact time should be at least one hour. Chemicals Methyl bromide was among the most widely used fumigants until its production and use was restricted by the Montreal Protocol due to its role in ozone depletion. 1,3-dichloropropene dazomet (methyl isothiocyanate precursor) chloropicrin DBCP formaldehyde hydrogen cyanide iodoform methyl isocyanate phosphine sulfuryl fluoride sulfur dioxide Safety Fumigation is a hazardous operation. Generally it is a legal requirement that the operator who carries out the fumigation operation holds official certification to perform the fumigation, as the chemicals used are toxic to most forms of life, including humans. Post operation ventilation of the area is a critical safety aspect of fumigation. It is important to distinguish between the pack or source of the fumigant gas and the environment which has been fumigated. While the fumigant pack may be safe and spent, the space will still hold the fumigant gas until it has been ventilated. See also ISPM 15 FAO Fumigation Manual Health and safety guidance for employers and technicians carrying out fumigation operations (‘Contains public sector information published by the Health and Safety Executive and licensed under the Open Government Licence’) Early publication W. G. Johnson, Fumigation Methods (New York, 1902) References External links National Pesticide Information Center Pest control techniques Pesticides es:Fumigación