Contamination Terms

1. Contamination Terms • Contamination — The process of transferring a hazardous material from its source to people, animals, the environment, or equipment • Decontamination • The process of removing hazardous materials to prevent the spread of contaminants beyond a specific area and reduce the level of contamination to levels that are no longer harmful • Is performed when a victim, responder, animal, or equipment leaves the hot zone (1 of 2) Operational Level

2. Contamination Terms • Secondary contamination — The contamination of people, equipment, or the environment outside of the hot zone • Exposure — The process by which people, animals, the environment, and equipment are subjected to or actually come in contact with a hazardous material • Hazard — The harm that can be done by a material (2 of 2) Operational Level

3. Types of Contamination • Primary • The direct transfer of a hazardous material to persons, equipment, and the environment • Occurs in the hot zone because of direct contact with a hazardous material (1 of 3) Operational Level

4. Types of Contamination • Secondary • The contamination of people, of equipment, or the environment outside the hot zone • The contaminant is carried from the hot zone by personnel’s clothing or tools, air currents, and runoff water. • If personnel are not decontaminated before leaving the hot zone, they can contaminate whomever and whatever they touch thereafter. (2 of 3) Operational Level

5. Types of Contamination • Surface • The contamination of the surface of a material • Does not penetrate, permeate, or soak into materials • Permeation • The penetration of a contaminant below the surface of a material (3 of 3) Operational Level

6. Categories of Decontamination • Gross • Emergency • Technical (formal) • Mass • Secondary • Definitive • Patient • Buddy • Self (1 of 4) Operational Level

7. Decontamination Methods • Wet • Washing the contaminated surface with solutions or flushing with a hose stream or safety shower • Usually necessitates the collection of runoff water in wading pools or other liquid-retaining devices • Dry • Scraping, brushing, and absorption • May be as simple as removing contaminated clothing and putting into a 55-gallon (208 L) storage bag • Does not create large amounts of contaminated runoff (1 of 2) Operational Level

8. Decontamination Methods • Physical • Removes the contaminant from a contaminated person without changing the material chemically • The contaminant is contained for disposal • Chemical • To make the contaminant less harmful by changing it through some kind of chemical process (2 of 2) Operational Level

9. Emergency Decontamination • When it is needed: • Failure of protective clothing • Accidental contamination of first responders • Heat illness or other injury suffered by emergency workers in the hot zone • Immediate medical attention required for other victims (1 of 2) Operational Level

10. Emergency Decontamination • Advantages • Requires minimal equipment • Reduces contamination quickly • Does not require a formal contamination reduction corridor or decontamination process • Limitations • Does not always totally decontaminate the victim • Creates contaminated runoff that can harm the environment and other exposures (2 of 2) Operational Level

11. Steps in Emergency Decontamination • Remove the victim from the contaminated area. • Wash immediately any exposed body parts with flooding quantities of water. • Remove victim’s clothing and/or PPE rapidly – if possible, cutting from the top down in a matter that minimizes the spread of contaminants. (1 of 2) Operational Level

12. Steps in Emergency Decontamination • Perform a quick cycle of head-to-toe rinse, wash, and rinse. • Transfer the victim to treatment personnel for assessment, first aid, and medical treatment. • Ensure that ambulance and hospital personnel are told about the contaminant involved. (2 of 2) Operational Level

13. Technical (Formal) Decontamination • Absorption • Picking up liquid contaminants with absorbents • Advantage — Absorbents are inexpensive and readily available • Limitations • Absorbents do not alter the hazardous material • Absorbents have limited use on protective clothing and vertical surfaces • Absorbent disposal may be a problem (1 of 9) Operational Level

14. Technical (Formal)Decontamination • Adsorption • Process in which a hazardous liquid interacts with (or is bound to) the surface of a sorbent material • Brushing or scraping • Removing large particles of contaminant or contaminated materials such as mud from boots or other PPE • Is not sufficient decontamination • Is used before other types of decontamination (2 of 9) Operational Level

15. Technical (Formal)Decontamination • Chemical degradation • Using another material to change the chemical structure of a hazardous material • Commonly used materials • Household bleach • Isopropyl alcohol • Hydrated lime • Household drain cleaner • Baking soda • Liquid detergents (3 of 9) Operational Level

16. Technical (Formal)Decontamination • Chemical degradation • Advantage — Can reduce cleanup costs and the risk posed to the first responder • Limitations • Takes time to determine the right chemical to use and set up the process • Can be harmful to first responders if the process creates heat and toxic vapors (4 of 9) Operational Level

17. Technical (Formal)Decontamination • Dilution • Using water to flush contaminants from contaminated victims or objects and diluting water-soluble hazardous materials to safe levels • Advantage — The accessibility, speed, and economy of using water • Limitations • Water may cause a reaction and create even more serious problems. • Runoff water from the process is still contaminated and must be confined and then disposed of properly. (5 of 9) Operational Level

18. Technical (Formal)Decontamination • Neutralization • Changing the pH of a corrosive, raising, or lowering, it towards 7 (neutral) on the pH scale • Sanitization, disinfection, or sterilization • Sanitization — Reduces the number of microorganisms to a safe level (such as by washing hands with soap and water) • Disinfection — Kills most of the organisms present • Sterilization — Kills all microorganisms present, with chemicals, steam, heat, or radiation (6 of 9) Operational Level

19. Technical (Formal)Decontamination • Solidification — Process that treats a hazardous liquid chemically so that it turns into a solid • Vacuuming — Process using high efficiency particulate air (HEPA) filter vacuum cleaners to vacuum solid materials such as fibers, dusts, powders, and particulates from surfaces (7 of 9) Operational Level

20. Technical (Formal)Decontamination • Washing • Process similar to dilution, but also involves using prepared solutions such as solvents, soap, and/or detergents mixed with water in order to make the contaminant more water-soluble before rinsing with plain water • Evaporation • Can be accomplished by simply waiting long enough for hazardous materials to evaporate (8 of 9) Operational Level

21. Technical (Formal)Decontamination • Isolation and disposal • Isolating the contaminated items by collecting them in some fashion and then disposing of them in accordance with applicable regulations and laws (9 of 9) Operational Level

22. Factors to Consider when Choosing a Decontamination Site • Accessibility • Must be away from hazards, but adjacent to the hot zone • Crucial time periods to consider • Travel time in the hot zone • Time allotted to work in the hot zone • Travel time back to the decontamination site • Decontamination time (1 of 4) Operational Level

23. Factors to Consider when Choosing a Decontamination Site • Terrain and surface material • The decontamination site ideally slopes toward the hot zone. • Diking around the site prevents accidental contamination escaping. • It is best if the site has a hard, nonporous surface to prevent ground contamination. • When a hard-surface driveway, parking lot, or street is not accessible, some type of impervious covering may be used to cover the ground. • Use covers or sheeting to form the decontamination corridor regardless of whether the surface is porous. (2 of 4) Operational Level

24. Factors to Consider when Choosing a Decontamination Site • Lighting (and electrical supply) • A site illuminated by streetlights, floodlights, or other type of permanent lighting reduces the need for portable lighting • Drains and waterways • Avoid locating a site near storm or sewer drains, ponds, ditches, and other waterways. • Water supply • Water (and sometimes detergent) must be available. (3 of 4) Operational Level

25. Factors to Consider when Choosing a Decontamination Site • Weather • Set up the site upwind in order to prevent the spread of contaminants into clean areas. • Make every attempt to shield victims from cold winds while they are removing protective clothing. (4 of 4) Operational Level

26. Setting up aDecontamination Corridor • Ensure privacy. • Provide a private, restricted area in which to conduct decontamination. • Use female responders to assist whenever possible when decontaminating women. (1 of 2) Operational Level

27. Setting up aDecontamination Corridor • Bag and tag contaminated clothing/effects carefully. • Label bags whenever possible. • Separate personal effects into clear plastic bags clearly marked with the person’s name. • Mark all personal effects so that they can be returned to their proper ownders after the incident without confusion. • Make the corridor visually recognizable – with barrier tape, safety cones, etc. (2 of 2) Operational Level

28. Decontamination Corridor Operational Level