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509. Chapter 11 Decontamination. Textbook Page. Objectives. Define The Following Terms Area Of safe Refuge Area Contaminant Contamination Decontamination Decontamination Corridor Decontamination Officer Decontamination Team Degradation Disinfection Emergency Decontamination.
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509 Chapter 11Decontamination Textbook Page
Objectives • Define The Following Terms • Area Of safe Refuge Area • Contaminant • Contamination • Decontamination • Decontamination Corridor • Decontamination Officer • Decontamination Team • Degradation • Disinfection • Emergency Decontamination
Objectives • Exposure • Mass Decontamination • Gross Decontamination • Technical Decontamination • Sterilization • Describe The Difference Between Contamination And Exposure, And Their Significance In Decontamination Operations. • Describe The Difference Between Surface Contamination And Permeation Contamination, And Their Significance In Decontamination Operations.
Objectives • Describe The Difference Between Direct Contamination And Cross Contamination, And Their Significance In Site Safety Operations. • Define The Following Terms And Describe Their Potential Harmful Effects To The Human Body Relating To Contamination: • Highly Acute Toxicity Contaminants • Moderate To Highly Chronic Toxicity Contaminants • Embryo toxic Contaminants • Allergenic Contaminants • Flammable Contaminants
Objectives • Highly Reactive Or Explosive Contaminants • Water Reactive Contaminants • Etiologic Contaminants • Radioactive Contaminants • Describe The Phases Of The Decontamination Process And Their Significance In DECON Operations • Gross DECON • Secondary DECON
Objectives • Describe The Following Types Of Decontamination Operations, And Their Application And Implementation At A Hazardous Materials Incident. • Emergency DECON • Technical DECON • Mass DECON
Objectives • Identify The Advantages And Limitations, And Describe An Example Where Each Of The Following Decontamination Methods Would Be Used: [NFPA 472 - 6.3.4(1)] • Absorption • Adsorption • Brushing And Scraping • Chemical Degradation • Dilution • Disinfection
Objectives • Sterilization • Evaporation • Heating And Freezing • Isolation And Disposal (I.E., “Dry DECON”) • Neutralization • Pressurized Air • Solidification • Vacuuming • Washing • Evaporation
Objectives • Identify Three Sources Of Technical Information For Selecting Decontamination Procedures And Identify How To Contact Those Sources In An Emergency. [NFPA 472 - 6.3.4(2)] • Identify Considerations Associated With The Placement, Set-up And Operation Of The Decontamination Area. [NFPA 472 - 6.3.4]
Objectives • List Three Types Of Fixed Or Engineered Safety Systems Which May Be Used To Assist Emergency Responders In Implementing DECON Operations Within Special Hazmat Facilities. • Define The Term "Clean-up" And Its Coordination With Decontamination Operations. • Describe Four General Clean-up Concerns When Decontaminating Equipment.
Introduction • Proper DECON Is Essential To Ensure The Safety Of Emergency Responders And The Public. • In This Text, We Have Adopted The Decon Terminology Referenced In NFPA 471, 472 And 473. • The Simplicity Of Decontamination Has Been Compared To Changing An Infant’s Diaper • Remove It From Others • Keep It Off Yourself • Don’t Spread It Around! • DECON Needs To Be An Adaptive And Flexible Procedure
512 Basic Principles Of Decontamination • The Process Of Decontamination Basically Involves The Physical Removal Or Neutralization Of Contaminants From Personnel And Equipment. • The Entire Process Of Decontamination Should Be Directed Toward Confinement Of The Contaminant Within The Hot Zone And Neutralizing It Within The DECON Corridor To Maintain The Safety And Health Of Response Personnel, And The General Public. • The Best Method Of Decontamination Is To Avoid Contamination.
Terminology And Definitions • Contaminant • Contamination • Exposure • Decontamination • DECON • Contamination Reduction • Degradation • Disinfection • Sterilization
Terminology And Definitions • Safe Refuge Area • Decontamination Team • Decontamination Corridor • Phase and Methods of DECON • Gross Decontamination • Secondary Decontamination • Emergency Decontamination • Technical Decontamination • Mass Decontamination
Understanding The Basics Of Contamination • The Level Of DECON Will Always Be Based Upon The Level Of Contamination. • Four Basic Concepts Of Contamination Are: • How To Prevent Contamination • Surface Vs. Permeation Contamination • Direct Vs. Cross Contamination • Types Of Contaminants
Preventing Contamination • Contamination Is Any Form Of Hazardous Material (Solid, Liquid, Or Gas) That Physically Remains On People, Animals, Or Objects. • Exposure Means That A Person Has Been Subjected To A Toxic Substance Or Harmful Physical Agent Through Any Route Of Entry Into The Body (E.G., Inhalation, Ingestion, Injection, Or By Direct Contact (Skin Absorption). • A Responder Who Has Been “Contaminated” When Wearing PPE Has Not Necessarily Been “Exposed.”
Preventing Contamination • Exposures Can Occur Through A Breach Or Failure Of PPE, The Exposure Can Occur If The PPE Is Accidentally Breached During An Operation, But PPE Failures Rarely Happen. • The Most Common Cause Of Contamination Comes From Poor Decontamination And Clean-up Operations. • Consider The Following Basic Principles To Prevent Contamination: • Stress Work Practices That Minimize Contact With Hazardous Substances.
Preventing Contamination • If Contact Is Made With A Contaminant, Move Contaminated ERP Personnel To An Area Of safe Refuge Area Within The Hot Zone Until They Can Be Decontaminated. • Keep Your Respiratory Protection SCBA Or Air Purifying Respirator (Apr) On As Long As Possible During The DECON Process. • Use Of Limited- Use / Disposable Protective Clothing Or Over-garments Can Significantly “Lighten” Your DECON Requirements. • Use A Systematic Approach To DECON. Don’t “Wing It.”
Surface Vs. Permeation Contamination • Surface Contaminants Are Found On The Outer Surface Of A Material But Have Not Been Absorbed Into The Material.
Surface Vs. Permeation Contamination • Permeation Contaminants Are Absorbed Into A Material At The Molecular Level. Permeated Contaminants Are Often Difficult Or Impossible To Detect And Remove.
Surface Vs. Permeation Contamination • Factors That Influence Permeation Include: • Contact Time • Concentration • Temperature • Physical State
Direct Vs. Cross Contamination • Direct Contamination Occurs When A Person Comes In Direct Physical Contact With A Contaminant. Direct Contamination Can Also Happen , Or When A Person Comes Into Contact With Any Object That Has The Contaminant On It • Cross Contamination (A.K.A. Secondary Contamination) Occurs When A Person Who Is Already Contaminated Makes Contact With A Person Or Object That Is Not Contaminated.
Direct Vs. Cross Contamination • Once The Contaminated Individual Person Physically Contacts The Uncontaminated Person, The Contaminant Is Transferred And Both Individuals Are Now Contaminated To The Other Person, And They Are Now Also Contaminated. • This Process Of Cross Contamination Can Go On And On, And Spread From One Person To The Next As They Touch More People And Objects.
Types Of Contaminants • The Types Of Contaminants Can Be Divided Into Eight Different Categories Based On Their Primary Hazards. These Include: • Highly Acute Toxicity Contaminants • Moderate To High Chronic Toxicity Contaminants • Embryotoxic Contaminants • Allergenic Contaminants • Flammable Contaminants • Highly Reactive Or Explosive Contaminants • Water Reactive Contaminants
Types Of Contaminants • Etiologic Contaminants • Virulence • Dose • Physical Environment • Personal Health Status • Radioactive Contaminants • Alpha Emmiters • Beta Emmiters • Gamma Emitters • All Three Hazards May Present
521 Decontamination Methods • Decontamination Methods Can Be Divided Into Two Basic Categories: Physical And Chemical. • Physical Methods Generally Involve “Physically” Removing The Contaminant From The Contaminated Person Or Object. • Chemical Methods Generally Involve Removing The Contaminant Through Some Type Of Chemical Process.
Examples of Physical Methods • Absorption • Absorbent Works By “Soaking Up” The Contaminant • Adsorption • Adsorbent Adds Itself Or “Sticks To” The Contaminant. • Brushing Or Scraping • Freezing
Examples of Physical Methods • Dilution / Washing • Isolation And Disposal • Heating • Pressurized Air • Vacuuming • Evaporation
Examples of Chemical Methods • Chemical Degradation • Commonly Used Degradation Agents Include Calcium Hypochlorite Bleach, Sodium Hypochlorite Bleach, Sodium Hydroxide As A Saturated Solution (Household Drain Cleaner), Sodium Carbonate Slurry (Washing Soda), Calcium Oxide • Degradation Chemicals Should Never Be Applied Directly To The Skin! Note: The Use Of Sodium Hypochlorite Or Bleach Solutions Can Have Adverse Effects On Any Firefighting Protective Clothing Or Equipment Using Kevlar Or Kevlar Blends
Examples of Chemical Methods … • Neutralization • Solidification • Disinfection • There Are Two Major Categories Of Disinfectants: • Chemical Disinfectants • Antiseptic Disinfectants • Sterilization
Effectiveness Of Decon Operations • The Effectiveness Of Any DECON Method Should Be Assessed At The Beginning And Periodically Throughout The Operation. • Criteria For Evaluating DECON Effectiveness: • No Personnel Are Exposed To Concentrations Above The TLV/TWA. • Personnel Are Not Exposed To Skin Contact With Materials Presenting A Skin Hazard. • Contamination Levels Are Reduced As Personnel Move Through The DECON Corridor.
Effectiveness Of Decontamination • Contamination Is Confined To The Hot Zone And DECON Corridor. • Contamination Is Reduced To A Level That Is As Low As Reasonably Achievable (ALARA). • Methods for Assessing Effectiveness of DECON • Visual Observation • Monitoring Devices • Wipe Sampling • Note: It Should Be Noted That There Is Currently No Practical Way To Determine The Effectiveness Of Decontamination In The Field For Most Etiologic Hazards.
527 DECON Site Selection And Management • Before Initiating Decontamination, The IC And The DECON Officer Must Decide • How Much And What DECON Method Is Required • To What Extent DECON Will Be Accomplished In The Field. • These Decisions Should Be Based On The Answers To The Following Questions: • Can DECON Be Conducted Safely? • Are Existing Resources Immediately Available To DECON Personnel And Equipment? • Can The Equipment Used Be Decontaminated?
The Decontamination Team • DECON Team Functions Include: • Research And Development Of The DECON Plan • Set-up And Operation Of An Effective Decontamination Area • Capable Of Handling All Potential Exposures • Entry Personnel • Contaminated Patients • And Equipment. • The DECON Team Is Managed By The DECON Officer, Who Reports To The Hazmat Branch Supervisor.
The Decontamination Team … • The DECON Officer Performs The Following Activities: • Determine The Appropriate Level Of Decontamination To Be Provided. • Ensure That Proper DECON Procedures Are Used By The DECON Team, Including DECON Area Set-up, DECON Methods And Procedures, Staffing, And Protective Clothing Requirements. • Coordinate DECON Operations With The Entry Officer And Other Personnel Within The Hazmat Branch.
The Decontamination Team … • Coordinate The Transfer Of Decontaminated Patients Requiring Medical Treatment And Transportation With The Hazmat Medical Group. • Ensure That The DECON Area Is Established Before Any Entry Personnel Are Allowed To Enter The Hot Zone, Whenever Possible. • Monitor The Effectiveness Of DECON Operations. • Appoint Or Act As An Accountability Officer To Limit Access To Personnel Entering And Operating Within The DECON Area.
The Decontamination Team … • Coordinate The Transfer Of Decontaminated Patients Requiring Medical Treatment And Transportation With The Hazmat Medical Group. • Ensure That The DECON Area Is Established Before Any Entry Personnel Are Allowed To Enter The Hot Zone, Whenever Possible. • Monitor The Effectiveness Of DECON Operations. • Appoint Or Act As An Accountability Officer To Limit Access To Personnel Entering And Operating Within The DECON Area.
DECON Site Selection • Outside The DECON Site Should Be Accessible Form A Hard Surface Road • Ideal Outdoor DECON Site Is Upwind And Uphill From The Incident • Attention Should Be Paid To Drains, Manholes And Waterways • Decon Indoors Consideration Should Be Given To Hallways, Slope Of The Floor, Drains And Ventilation Air Flow
DECON Site Selection • Complete DECON May Be Impractical To Achieve At A Single Location, So A Combination Of On-site And Off-site Contingencies May Be Necessary. • The DECON Corridor Is Simply A Pathway From The Hot Zone Into The DECON Area • Some Scenarios Will Require Multiple DECON Corridors. • Response Scenarios In Which The DECON Area Is Physically Separated From The “Problem” By A Large Distance Can Pose Additional Challenges For Responders.
Staffing And Personal Protection • The DECON Officer Should Be Trained To The Hazardous Materials Technician Level (Or Equivalent). • Each Staffed DECON Station Should Have At Least One DECON Member Assigned • Those Stations Which Require Entry Personnel To Be Scrubbed Or To Remove Their PPE Should Be Staffed With Two DECON Members, If Possible.
Staffing And Personal Protection • The Level Of Skin And Respiratory Protection Required By DECON Team Members Will Be Dependent Upon: • The Type Of Contaminants Involved • The Level Of Contamination Encountered By Entry Personnel • Where Individuals Are Working Along The DECON Line.
Tactical And Safety Considerations • The DECON Team Should Be Dressed In Chemical Protective Clothing And Equipment Based On The Hazards And Risks Of The Contaminants They Will Be Decontaminating. • The Most Common Level Of Protection For The DECON Team Is Chemical Splash Protective Clothing • Extended Entry Operations Will Require That The DECON Team Be Provided With An Uninterrupted Air Supply.
Tactical And Safety Considerations • Respiratory Protection For DECON Team Members May Be Downgraded To PAPR's Or APR's Providing That Air Monitoring Is Conducted And Filter Cartridges Are Compatible With The Concentration Of Contaminants Present. • All DECON Team Personnel Must Be Decontaminated Before Leaving The DECON Area
532 Types Of Decontamination Field DECON • While There Are A Variety Of Different Approaches To DECON, The Better Standard Operating Procedures Are Built Around Several Basic Principles: • Contaminated People And Equipment Generally Flow From The Dirty End (Area Of Highest Contamination) To The Clean End (Area Of Least Contamination). • Just Like The Car Wash, Decontamination Requires A Multiple-step Process To Reduce Contaminants To An Acceptable Level. • Conducting All Of The Cleaning Process At One Station Concentrates All Of The Contamination In One Area. • Multiple Decontamination Stations Make You Cleaner.
Types Of Decontamination • Multi-step DECON Operations Can Be Broken Into Two Broad Phases: • Gross Decontamination—The Initial Phase Of The Decontamination Process During Which The Amount Of Surface Contaminant Is Significantly Reduced. In Simple Terms, It Is Designed To Remove Most Of The “Big Stuff.” • Secondary Decontamination–The Second Phase Of The Decontamination Process Designed To Physically Or Chemically Remove Surface Contaminants To A Safe And Acceptable Level. • Depending On The Scope And Nature Of The Incident, Multiple Secondary DECON Steps May Be Implemented. • Technical DECON Incorporates Both Gross And Secondary Phases.
DECON Information Sources • Sources For Determining The Appropriate DECON Methods And Related Information Can Include: • Product Specialists • Technical Information Specialists • Technical Information Centers, • Material Safety Data Sheets (MSDS) • Emergency Response Guidebooks • Some Online Computer Databases Now Incorporate DECON Information.
DECON Information Sources – Bottom Line • Bottom Line: There Is No One Single Best Resource For Acquiring Field Decontamination Information. • Remember The “Rule Of Three’s” • Failure To Consult With “Live, Talking Technical Information Sources” At Working Hazmat Incidents With High Technical Or Political Risks Will Increase The Potential For An Unacceptable Outcome
Types of DECON • Different Type of Decontamination may be required based on the nature of the Problem, urgency of the situation, the number of people contaminated, and the scope of contamination. • The Three Types of Decontamination • Emergency Decon • Technical Decon • Mass Decon
Types of DECON 533