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Controls in Biosafety II: Work Practices and Personal Protective Equipment. EMD 545b Lecture #6. Biosafety Work Practices. Foundation matrix Routes of Exposure on Y axis 7 Basic biosafety work practices on X axis Which practices block each route of exposure?
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Controls in Biosafety II:Work Practices and Personal Protective Equipment EMD 545b Lecture #6
Biosafety Work Practices • Foundation matrix • Routes of Exposure on Y axis • 7 Basic biosafety work practices on X axis • Which practices block each route of exposure? • Majority of biosafety work practices stem from the core 7 practices
Routes of Exposure • Ingestion • Inhalation • Mucous membranes (eyes, nose, mouth) • Percutaneous
Biosafety Work Practices • No mouth pipetting • No eating, drinking, smoking, food storage • Wear personal protective equipment • Work carefully to avoid creation of aerosols • Eliminate/avoid the use of sharps • Decontaminate work surfaces/spills • Wash hands after removing PPE, skin contact (keep hands away from face)
Biosafety Work Practices • Administrative • establish safety policies (written SOP) • restrict access to lab to those involved in work • post entry requirements (immunizations, PPE) • labels on equipment storing biohazards, door sign with agent and contact information • ensure training for all who work with hazards • advise all workers of any special hazards • workers must demonstrate proficiency
Biosafety Work Practices • Transport/Shipping • use two leak proof labeled containers for on-campus shipment (include contact info) • avoid the use of glass primary or secondary containers whenever feasible • Use UN-Approved infectious substance shippers for public roadways, air, other methods of conveyance • All shippers/transporters trained biennially
Biosafety Work Practices • Contain other aerosol generating procedures • any procedure that imparts energy to a microbial culture, includes: • homogenizing, blending, shaking, grinding • vortexing, mixing, pipetting, spills • opening tubes which are under pressure (vacutainer) • removing syringe from vial, expelling air • animal bedding, cage dust, animal hair, necropsy • droplets from pipets to bench, liquid to liquid (from height), forcibly expelling liquid from pipette
Bioafety Work Practices • Personnel • ensure reporting of all near misses or incidents • report immunosuppression/compromised skin • evaluate new procedures before initiation • never initiate work without authorization • address all medical requirements before starting • know signs/symptoms of disease, report them • always work carefully, avoid short cuts, follow written SOP’s • keep pets, other unrelated items out of lab
Foundational Biosafety Practices • Hand washing • No mouth pipetting • No eating or drinking in lab • Minimize aerosol generation • Decontaminate work surfaces • Safe sharps handling • Wear applicable PPE
Foundational Biosafety Practice #1 Confine Aerosols
Aerosols • Procedures that impart energy into a microbial suspension are a potential source of aerosol (Chatigny, 1974) • Many common lab procedures and accidents have capability of releasing aerosols • homogenization, sonication, blending, mixing, grinding, shaking, vortexing, spills, opening vials, pipetting, animals excreting agent, opening vials under pressure, etc.
Confine Aerosols! Promote Awareness of: • Aerosol containment • Work Practices & PPE • Emergency Response Procedures • Minimize/prevent lab-acquired infections
Procedure sonic oscillator mixing w/ pipette overflow from mixer opening lyophilized vial top removed after blending dropping flask of culture dropping lyophilized culture # Particles/ft3 of air 6 7 9 135 1500 1551 4839 Viable Particles Recovered from Air(Chatigny, 1974)
Correct Use of Biosafety Cabinets • Purge air before and after use • Load supplies prior to work • Wipe items with disinfectant before loading (or removing) • Clean up spills promptly
Biosafety Work Practices • Effective Use of the Biosafety Cabinet • use to contain aerosols (pipetting, other work) • decontaminate interior before/after use • work at least 4” inside front grille • minimize movement of hands out of cabinet • keep traffic behind operator to a minimum • avoid the use of an open flame inside cabinet
Centrifuge Containment • Load/unload sealed buckets in a biosafety cabinet • Wait 2 to 5 minutes after run to allow aerosols to settle • Decontaminate centrifuge and buckets after each use
Biosafety Work Practices • Centrifugation Precautions • use secondary containment (decon after use) • check tubes for cracks or deformities before use • always use sealed primary tubes • don’t overfill primary containers • balance loads to avoid damage to centrifuge • unit should have solid lid and interlock
Emergency Response • Aerosol exposure • BL2 • leave lab upon release • Wash wounds, flush face/eyes if exposed, wash hands • post sign, keep area vacated for 20 - 30 minutes to allow aerosols to settle • decontaminate personnel clothing, skin • notify lab supervisor, biosafety, and Health Services if necessary
Foundational Biosafety Practice #2 Hand Washing
Hand Washing • Hands must be washed after removing: • gloves • other PPE • and whenever gloves are damaged or torn
Foundational Biosafety Practice #3 No Mouth Pipetting
Careful Pipetting Techniques • Never blow out last drop in pipette • Use pipette aids with filters • Horizontal pipette collection tubs • Never mix by suction + expulsion
Minimize Aerosols • Careful pipetting practices • Avoid drops onto hard surfaces • Wipe up spills promptly with appropriate disinfectant
Careful Pipetting Techniques • Discharge liquid down side of container • Deliver as close as possible to contents • Work over plastic-backed absorbent matting
Avoid Splatter 3 Correct 1 Incorrect 2 Incorrect
Minimize Aerosols • Use capped tubes when mixing, blending, or vortexing • Pour liquids carefully • Avoid bubbles
Foundational Biosafety Practice #4 Eliminate or Work Safely with Sharps
Use Extreme Care with Sharps • Percutaneous exposure risk • Employ safe work practices • Utilize safe sharp devices • Aerosol risk • Use biosafety cabinet for removal of air from needle • Sharps also includes scalpels, blades and wires.
Only use sharps if absolutely required as part of a process. Ongoing evaluation of new safety devices Safe Sharps Devices
Keep hands away from needles. Use mechanical methods for needle removal. Never bend, recap or manipulate sharps by hand. Safe Use of Sharps
Dispose of entire unit into sharps container. Collect reusable sharps in labeled, leak proof container. Safe Use of SharpsDisposal/Reprocessing
Infectious Waste Disposal • All cultures and stocks are decontaminated before disposal. • Wastes must be in closed containers for transport out of lab. • Infectious waste containers must be labeled.
Infectious Waste Disposal • Written SOP’s for: • Waste management • Regulated sharps • Other sharps (tips, pipettes, glass items, etc.) • Liquid waste
Foundational Biosafety Practice #5 No Eating, Drinking or Smoking (Avoid touching your eyes, nose, mouth)
Foundational Biosafety Practice #6 Personal Protective Equipment (PPE)
Personal Protective Equipment (PPE) Purpose of PPE: • Barrier against skin, mucous membrane or respiratory exposure to infectious agents • To prevent spread of contamination.
Laboratory Clothing • Protects the worker from splash and splatter during procedures. • Protects worker’s clothing from contamination. • Can be used to protect product from contamination.
Choice of fabric: must be appropriate for use Fire retardant and resistant to chemicals Water repellant if risk of splash and splatter. Can add plastic apron Type and use must be prescribed in SOP or manual and staff trained Laboratory Clothing: Important Considerations
Laboratory Clothing: Important Considerations • Staff must be trained in aseptic removal procedures-gloves last! • Reusable clothing must withstand autoclaving • Laundry facilities must be provided. Lab clothing not to be taken home.
Removing Gloves 1 2
Removing Gloves 1 2 3
Removing Gloves 1 4 2 3
Gloves: Important Considerations • Avoid wetting gloves (disinfectants enhance permeation) • Change gloves as soon as feasible after contamination • Use utility gloves or double glove for spills • Examine utility gloves after washing for integrity
Personal Protective Equipment (PPE) • Limitations of PPE: • Does not eliminate the hazard. • Integrity wanes with use (change gloves frequently) • Not all gloves created equal - select best glove for the task.