Fumigation procedures

Because certain f imdamental concepts were demonstrated for the first time in the Sampson projects, the tests will be described in sufficient detail to explain why fogs were used instead of standard fumigation procedures the insects involved will be mentioned as well as what happened to them. 

Kassim, G., Martin J. R, and Haider, K. (1981). Incorporation of a wide variety of organic substrate carbons into soil biomass as estimated by the fumigation procedure. Soil Sci. Soc. Am. J. 45,1106-1112. 

Two new methods for measuring soil microbial P have been described, based on the widely used CHCI3- fumigation procedure for measuring the soil microbial biomass. In these methods, the P released from microbial cells following lysis with CHClg is extracted from the soil with NaHCO. Some of this P will be immediately fixed by soil colloids, and in one methoda spike of P is used to correct for this. The other method is calibrated for recovery of microbial P for each soil type. Non-microbial P was not affected to any extent by fumigation. 

Inversion Break-up Fumigation - The inversion break-up screening calculations are based on procedures described in the Workbook of Atmospheric Dispersion Estimates (Turner, 1970). The distance to maximum fumigation is based on an estimate of the time required for the mixing layer to develop from the top of the stack to the top of the plume, using ... 

In the evaluation of ethylene dibromide as a soil fumigant, a sensitive procedure was needed for determining concentrations lower than 0.2 mg. per cubic inch in soil. When the method of Brenner and Poland was used, addition of a small quantity of acetic acid considerably increased the percentage of ethylene dibromide recovered. 

Kerwin et al. [41] determined methyl bromide soil fumigant by cyrotrapping and electron capture gas chromatography. Down to 0.23pM of methyl bromide could be detected by this procedure. Kerwin et al. [41] found levels of methyl bromide in the stratosphere and claimed that this contributed to ozone destruction. 

The document lists common technical grade pesticides and recommended classihcations together with a listing of active ingredients believed to be obsolete or discontinued for use as pesticides, pesticides subject to the prior informed consent procedure, limitations to trade because of the Persistent Organic Pollutants (POPs) convention (UN 2001), and gaseous or volatile fumigants not classified under these recommendations. 

The layout and design of production areas and equipment should permit effective cleaning and decontamination (e.g. by fumigation). The adequacy of cleaning and decontamination procedures should be validated. 

Various other workers have reported on the determination of volatile organic compounds in soils [186,187] and landfill soils [188]. Soil fumigants such as methyl bromide have also been determined by this technique [189]. Trifluoroacetic acid is a breakdown product of hydrofluorocarbons and hydrochlorofluorocarbon refrigerant products in the atmosphere and, as such, due to the known toxicity of trifluoroacetic acid, it is important to be able to determine it in the atmosphere, water and in soil from an environmental point of view [190]. In this method the trifluoroacetic acid is extracted from the soil sample by sulfuric acid and methanol, which is then followed by the derivatisation of it to the methyl ester. The highly volatile methyl ester is then analysed with a recovery of 87% using headspace gas chromatography. Levels of trifluoroacetic acid in soil down to 0.2 ng/g can be determined by the procedure. 

Fig. 5 Single door to an execution gas chamber for one single person per gassing procedure (Baltimore, USA, 1954, technology from the 1930s). The execution of a single person with hydrogen cyanide is inevitably far more complicated and dangerous to the environment than the fumigation of clothing (even in a DEGESCH circulation chamber).

Chapter 1.3. contained a discussion of an instance of damage to a church which occurred in 1976 in Bavaria, Germany. In the many hundreds of thousands of fumigations which have been carried out since 1920, there cannot, as a rule, have been any complications, otherwise the procedure would have been very rapidly abandoned. The case in question was, therefore, an exception. But what exactly was it that made this church an exception ... 

Wu, J., Joergensen, R. G., Pommerening, B., Chaussod, R., and Brookes, P. C. (1990). Measurement of soil microbial biomass C by fumigation-extraction—An automated procedure. Soil Biol. Biochem. 22, 1167-1169. 

The regulations of that time stipulated that after every delousing procedure utilizing hydrogen cyanide, a hydrogen cyanide residue detector had to be used to test the fumigated facilities to determine whether ventilation had been successful. Only then could the deloused rooms be entered without a protective gas mask. 

Initially, ordinary rooms were turned into disinfestation facilities for material objects by means of makeshift alterations intended to render the windows and doors as gas-proof as possible and to provide adequate heating and ventilation systems for the rooms. Workers wearing protective masks distributed the Zyklon B evenly on the floor of the room, which had been previously stocked with the items to be fumigated. This procedure was similar to that used at the time for the fumigation of ordinary rooms for purposes of disinfestation. 

In such fumigations, gaseous toxins are distributed throughout the space in question. They are left to react for an appropriate period of time, and then the space is aired out and the toxins are removed to the outside world. Of course it is important that the facilities to be fumigated are sealed off as tightly as possible during the procedure. 

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