Dry decontamination is a method of removing

contaminants Contamination is the presence of a constituent, impurity, or some other undesirable element that renders something unsuitable, unfit or harmful for the physical body, natural environment, workplace, etc. Types of contamination Within the scie ...

(such as

chemicals A chemical substance is a unique form of matter with constant chemical composition and characteristic properties. Chemical substances may take the form of a single element or chemical compounds. If two or more chemical substances can be combin ...

biological Biology is the scientific study of life and living organisms. It is a broad natural science that encompasses a wide range of fields and unifying principles that explain the structure, function, growth, origin, evolution, and distribution of ...

particles, or other

liquid Liquid is a state of matter with a definite volume but no fixed shape. Liquids adapt to the shape of their container and are nearly incompressible, maintaining their volume even under pressure. The density of a liquid is usually close to th ...

gas Gas is a state of matter that has neither a fixed volume nor a fixed shape and is a compressible fluid. A ''pure gas'' is made up of individual atoms (e.g. a noble gas like neon) or molecules of either a single type of atom ( elements such as ...

ses, or

solid Solid is a state of matter where molecules are closely packed and can not slide past each other. Solids resist compression, expansion, or external forces that would alter its shape, with the degree to which they are resisted dependent upon the ...

s) without the need to use

water Water is an inorganic compound with the chemical formula . It is a transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance. It is the main constituent of Earth's hydrosphere and the fluids of all known liv ...

or other liquids.

Decontamination Decontamination (sometimes abbreviated as decon, dcon, or decontam) is the process of removing contaminants on an object or area, including chemicals, micro-organisms, and/or radioactive substances. This may be achieved by chemical reaction, dis ...

is an essential duty of

hazmat Hazmat, HazMat or HAZMAT may refer to: * Dangerous goods, hazardous materials and items * Hazmat suit * Hazmat diving * Hazmat (comics) is a Marvel Comics character * ''HazMat'' (film), a 2013 horror film See also * Hazmat Modine Hazmat Mo ...

responders as it protects victims from harmful reactions to the contaminants. Dry decontamination is a relatively recent method of decontamination and is especially useful in cold weather conditions, or when water is scarce or difficult to transport. Dry decontamination reduces the size and manpower requirements of the decontamination line and eliminates the need to purchase excess equipment that becomes ineffective due to storage or infrequent use.

Dry decontamination methods

Dry decontamination is usually performed after the removal of clothing and before a shower (when available). There are five different types of dry decontamination, each of which can be used in conjunction with others to remove up to 100% of all suspected contaminants:Rudner, Glen D. ''Emergency Responder Considerations for Decontamination of Incidents.'' # Scraping # Absorbent materials #

Adsorbent Adsorption is the adhesion of atoms, ions or molecules from a gas, liquid or dissolved solid to a surface. This process creates a film of the ''adsorbate'' on the surface of the ''adsorbent''. This process differs from absorption, in which a ...

materials # Vacuuming # Pressurized air

Scraping

Scraping is a process of decontamination in which the bulk contaminant is removed from the victim or environment using a

spatula A spatula is a broad, flat, flexible blade used to mix, spread and lift material including foods, drugs, plaster and paints. In medical applications, "spatula" may also be used synonymously with tongue depressor. The word ''spatula'' derives ...

, wooden

tongue depressor A tongue depressor or spatula is a tool used in medical practice to depress the tongue to allow for examination of the mouth and throat. Hobbyists, artists, teachers and confectionery makers use tongue depressors, which may also be referred to ...

, or other handheld implement. Scraping works best with

viscous Viscosity is a measure of a fluid's rate-dependent resistance to a change in shape or to movement of its neighboring portions relative to one another. For liquids, it corresponds to the informal concept of ''thickness''; for example, syrup h ...

liquids and solids.

Absorbent materials

Absorbent materials are specifically made to absorb (or capture and contain) contaminants. Absorbent materials include FiberTect, Reactive Skin Decontamination Lotion (RSDL),

Fuller's earth Fuller's earth is a term for various clays used as an absorbent, filter, or bleaching agent. Products labeled fuller's earth typically consist of palygorskite (also known as attapulgite) or bentonite. Primary modern uses include as absorbents ...

flour Flour is a powder made by Mill (grinding), grinding raw grains, List of root vegetables, roots, beans, Nut (fruit), nuts, or seeds. Flours are used to make many different foods. Cereal flour, particularly wheat flour, is the main ingredie ...

baking soda Sodium bicarbonate (IUPAC name: sodium hydrogencarbonate), commonly known as baking soda or bicarbonate of soda (or simply “bicarb” especially in the UK) is a chemical compound with the formula NaHCO3. It is a salt (chemistry), salt compose ...

paper towel A paper towel is an absorbent, disposable towel made from paper. In Commonwealth English, paper towels for kitchen use are also known as kitchen rolls, kitchen paper, or kitchen towels. For home use, paper towels are usually sold in a roll of p ...

s, etc., all of which absorb hazardous materials from the victim. After absorption is completed using an absorbent material and immediate danger has passed, the contaminated surface should be blotted with a wet paper towel. An absorbent material increases in volume when a contaminant is absorbed.

DEC'POL

The DEC'POL® Emergency Decontamination Mitt is a polyvalent device that incorporates superabsorbent material with active agents for the destruction of chemical and biological contamination. The mitt was developed and is produced in

Lyon Lyon (Franco-Provençal: ''Liyon'') is a city in France. It is located at the confluence of the rivers Rhône and Saône, to the northwest of the French Alps, southeast of Paris, north of Marseille, southwest of Geneva, Switzerland, north ...

, France, by clothes and fabric manufacturer Ouvry SAS. DEC'POL is available in cases of 20 mitts. 600003 DECPOL 1

FiberTect

FiberTect is a multi-layer

nonwoven Nonwoven fabric or non-woven fabric is a fabric-like material made from staple fibre (short) and long fibres (continuous long), bonded together by chemical, mechanical, heat or solvent treatment. The term is used in the textile manufacturing in ...

composite fabric that absorbs and adsorbs chemical, biological, and radiological contaminants. It is made of two layers of

polyester Polyester is a category of polymers that contain one or two ester linkages in every repeat unit of their main chain. As a specific material, it most commonly refers to a type called polyethylene terephthalate (PET). Polyesters include some natura ...

with an inner layer of fibrous activated

carbon Carbon () is a chemical element; it has chemical symbol, symbol C and atomic number 6. It is nonmetallic and tetravalence, tetravalent—meaning that its atoms are able to form up to four covalent bonds due to its valence shell exhibiting 4 ...

. The three layers are needle-punched to form a single fabric that allows the material to be structurally sound while creating void spaces for better absorption and

adsorption Adsorption is the adhesion of atoms, ions or molecules from a gas, liquid or dissolved solid to a surface. This process creates a film of the ''adsorbate'' on the surface of the ''adsorbent''. This process differs from absorption, in which a ...

. FiberTect is available in wipes or mitts, which remove up to 90% of contaminants.

RSDL

RSDL (or Reactive Skin Decontamination Lotion) consists of an absorbent sponge applicator and a lotion that neutralizes toxic agents. RSDL removes or neutralizes chemical warfare agents,

T-2 mycotoxin T-2 mycotoxin is a trichothecene mycotoxin. It is a naturally occurring mold byproduct of ''Fusarium'' spp. fungus which is toxic to humans and other animals. The clinical condition it causes is '' alimentary toxic aleukia'' and a host of sympto ...

s, and pesticides. RSDL is the standard decontamination means for many armed forces such as the US Army, Canadian Forces and the German Bundeswehr.

Fuller's earth

Fuller's earth is any clay material that has the ability to absorb oil, grease, etc. without chemical treatment. It is also used for filtering, clarifying, decoloring, and as a filler in paint. It is used by the military and first responders to decontaminate clothing and equipment.

Adsorbent materials

Adsorbent materials adhere to and encapsulate contaminants on various surfaces. Adsorbent materials do not increase in volume when a contaminant is absorbed.

Vacuuming

Vacuuming physically removes solid materials from victims and the contaminated environment. Vacuuming should only be done when the victim and all people in the vicinity are wearing respiratory protection and the usefulness of vacuuming can be limited by the availability of supplies, equipment, and electricity.

Pressurized air

Pressurized air uses low-pressure air streams to remove solid, dry contaminants from equipment and the environment. As with vacuuming, the use of pressurized air should be limited to situations where all people in the contaminated area are wearing personal protective equipment (PPE). The use of pressurized air is often not recommended because there are many hazards associated with the method, including respiratory and skin damage.

Dry decon vs. wet decon

Advantages of dry decontamination

Dry decontamination reduces concerns associated with cold weather decontamination while also speeding up the decontamination process by allowing victims to self-decontaminate (or be decontaminated by a

first responder A first responder is a person with specialized training who is among the first to arrive and provide assistance or incident resolution at the scene of an emergency. First responders typically include Law enforcement, law enforcement officers (co ...

with minimal cross-contamination). In addition, some contaminants are water-reactive and wet decontamination methods may only increase the potential hazards.

Time effectiveness

The deployment of a dry decontamination system allows the victim to assist in his/her own decontamination. In addition, dry decontamination operations are expedited by allowing for the quick removal of contaminants from the victim's skin, reducing the amount of time a victim is in contact with the contamination (which therefore minimizes the potential harm caused).

Cold weather decontamination

When conducting decontamination in temperatures below 36 °F, dry decontamination can be an effective solution that prevents more casualties resulting from

hypothermia Hypothermia is defined as a body core temperature below in humans. Symptoms depend on the temperature. In mild hypothermia, there is shivering and mental confusion. In moderate hypothermia, shivering stops and confusion increases. In severe ...

. Other sources recommend that wet decontamination be avoided in external temperatures of below 65 °F to avoid the adverse effects of

cold shock Cold shock response is a series of neurogenic cardio-respiratory responses caused by sudden immersion in cold water. In cold water immersions, such as by falling through thin ice, cold shock response is perhaps the most common cause of death. Al ...

Logistical issues

Wet decontamination lines require not only a water source, but occasionally electricity for deployment. As a rule, dry decontamination is faster both in deployment and clean-up as it does not require an immediate water supply, contaminated water collection basin, resources (like hoses, nozzles, shelters, and other large pieces of equipment), or a large number of personnel.

Mass casualty decontamination

Large-scale decontamination often involves civilians who, unlike soldiers and responders, are not trained in decontamination methods. Currently, wet decontamination is most frequently used in large-scale decontamination efforts, during which civilians are directed by soldiers and responders to shower (usually with water and a detergent or bleach). Dry decontamination is proving to be a safer, more effective method of decontamination for large-scale incidents.

References

{{Reflist Hygiene