Measuring and testing – Sampler – sample handling – etc. – With heating or cooling
Patent
1999-08-19
2000-09-12
Raevis, Robert
Measuring and testing
Sampler, sample handling, etc.
With heating or cooling
G01N 100
Patent
active
061160970
DESCRIPTION:
BRIEF SUMMARY
The invention relates to a method and means for detecting chemical contaminants on the ground. More specifically, the invention relates to a method and means for carrying out the detection from a moving vehicle.
At chemical and nuclear energy accidents such as release of toxic and hazardous compounds and at radioactive fallout and chemical attack during war, safe and rapid detection and mapping is essential for the continued work. Vehicles equipped with personal protection for the crew, so that the vehicles can be used in areas contaminated with chemical warfare agents or radioactive fallout, are previous known. Equipment for mapping radioactive fallout situations are relatively well provided for, but the presence of chemicals of low volatility on the ground can be difficult to detect. Chemical warfare agents are dispersed as droplets and can at low temperatures remain as a ground contamination for a considerable time and involve a urgent danger--contact risk--even if the evaporation and consequently the concentration in the surrounding air is low. The equipment used today for vehicle based mobile detection of chemical warfare agents present as a ground contamination is based on the principle that a sample is first taken from the ground surface, i.e. with a special silicon wheel which after sampling is lifted and analysed (Fuchs), or by measuring compounds in the form of vapour in the ambient air on different heights over the ground surface. The British Patent 2 259 572 relates to an equipment of the latter type.
An object of the present invention is to provide a simplified method and simplified means for vehicle based mobile detection of chemical contaminants on the ground and to make it possible to detect also small amounts of compounds with extremely low volatility and under difficult conditions such as low temperatures.
The invention is based on the recognition that when a vehicle is driven through a chemically contaminated area, for instance on a road or in the terrain, the vehicle will become more or less spattered, contaminated, by the chemical in question. All transport from the contaminated ground to the vehicle is caused by the wheels or tracks contacting the ground. The spattering is mainly directed backwards towards the area where cars usually have mudflaps. According to the invention, this fact has been utilised to achieve a method and means for detecting chemical contaminants on the ground.
The inventive method is characterised in that a wheeled or tracked vehicle having a sampling screen arranged as a mudflap in connection with at least one wheel/track of the vehicle is driven on the ground to be investigated, whereby said sampling screen is contaminated by particles thrown up from the ground, and that an air stream carrying substances evaporated from said particles is caused to flow from said sampling screen through a conduit via a detection unit in the vehicle.
In order to increase the evaporation of substances from the particles, the sampling screen preferably has a heating device.
The air stream carrying evaporated substances to the detection unit can be a result of the speed of the vehicle or be accomplished by a fan/air pump in the conduit.
At dry conditions a sprinkling device can be used for wetting the wheel with a liquid to increase the spatter of particles and consequently the sensitivity of the detection.
The vehicle can be a car, all terrain carrier, armoured personnel carrier etc. but can also be a trailer, which is equipped for the purpose. The track/wheel of the vehicle that is used for spattering particles on to the sampling screen does not have to be one of the regular tracks/wheels of the vehicle but can constitute a separate unit. When detecting CW agents or similar toxic compounds the vehicle can be equipped with a so called collective protection for the crew. That is, the vehicle is tight, an overpressure can be maintained in the passenger compartment and incoming ventilating air is filtered through a chemical agent adsorbing filter.
By the inventive method very small a
REFERENCES:
patent: 3420091 (1969-01-01), Franklin
patent: 3793887 (1974-02-01), Anderson et al.
patent: 4738147 (1988-04-01), Tomlin
patent: 4982616 (1991-01-01), Koch et al.
patent: 5437203 (1995-08-01), Koch et al.
patent: 5517026 (1996-05-01), Sickenberger et al.
Berglund Tage
Nyholm Sune
Olofsson Goran
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