EHS Flashcards
Biohazard def
Pathogenic and non-pathogenic microorganisms, proteins, and nucleic acids, as well as any biological matter that may contain microorganisms, proteins, nucleic acids, or parts thereof.
Biohazard examples
- Micro-organisms
- Viruses, fungi, parasites, prions, bacteria and toxins
- Human and animal blood and bodily fluids * Cell lines and other tissue cultures * Nucleic acids
- Genetically modified organisms
- Plants and algae
Laboratory-Acquired Infections (LAI) routes
- Direct contact (e.g. splash)
- Inhalation
- Ingestion
- Parenteral/inoculation
- Indirect contact
- Vectors: animal/insect
bites
Some aerosol generating procedures
: homogenizing, blending, grinding vortexing, mixing, pipetting centrifugation
opening snap-cap tubes
animal cage changing, necropsy
streaking agar plates
spills
Best protection against inhalation of aerosols and sources
Best protection is a Biological Safety Cabinet
Some aerosol generating procedures:
homogenizing, blending, grinding
vortexing, mixing, pipetting
centrifugation
opening snap-cap tubes
animal cage changing, necropsy
streaking agar plates
spills
What to do after accidental exposure to hazardous material
- Ask for help – provide immediate first aid
- Serious injury dial 911 and Security
- Needlesticks and cuts: wash with soap and water
- Splashes: flush eyes, mouth, nose
- If required, seek medical attention:
- Notifysupervisor
- Complete Accident, Incident & Occupational Disease Report
- Monitor for symptoms - incubation period
How many pathogen risk levels
Categorization of relative hazards of pathogens (4 levels)
* Known for most common pathogens
What determines pathogen risk level
For new pathogens:
* Pathogenicity
* Infectious dose
* Mode of transmission
* Host range
* Effective prevention, e.g. vaccine
* Effective treatment, e.g. antibiotic, antiviral PEP
Risk group definitions
Risk Group 1
* Low individual risk * Low community risk * Unlikely to infect healthy humans & animals
Risk Group 2
* Moderate individual risk * Low community risk * Treatment/prevention available
Risk Group 3
* High individual risk
* Low community risk
* Cause serious disease, treatment/prevention usually available
Risk Group 4
* High individual risk
* High community risk
* Cause serious or lethal disease by casual contact
* Treatment/prevention not usually available
Risk level vs containment level
Containment levels based on:
* Potential for aerosol generation
* Quantity
* Concentration
* In vitro, in vivo or large scale
* Shedding
Risk -> personal community risk and treatment possible
Containment levels
Containment Level 1
* Physical requirements: * Basic design features
* Operational requirements:
* Work may be done on open bench top
* BSC not required, may be used for sterility
* Good microbiological
practices (good hygiene)
Containment level 2
Additional physical requirements, e.g.
Limited access, signage, lockable doors
Resistant, non-absorptive surfaces (for disinfection)
Containment of aerosols, e.g.: BSC
Centrifuges with sealed rotors or safety cups Minimize environmental contamination:
Handwashing sinks Decontamination facilities (autoclaves)
Level 3
* Respiratory protection
* HEPA filtration of lab exhaust
* Strictly controlled access
Level 4
* Isolated facility with sealed perimeter
* Positive pressure suits or Class 3 BSC
* Effluent sterilization system
Local risk assessment
- Hazards: Identify hazards associated with tasks and procedures, break down into steps as necessary.
- Risk statement: An accurate picture of a risk, includes; the event itself and the potential negative impact if the risk is not managed.
Risk level based on = likelyhood of occurence * consequence
Risk mitigation steps
Elimination/ substitution:
Engineering Controls: (lighting, handwash stations, autoclave, BSC)
Administrative Controls: (limited access, record keeping, inventory)
Personal Protective Equipment (PPE):
Biosafety and biosecurity
Biosafety: containment principles, technologies and operational practices that are implemented to prevent unintentional exposure to pathogens or toxins
Biosecurity: measures designed to prevent the loss, theft, misuse, diversion or intentional release of infectious materials or toxins
Standard biosafety practices
No Eating, drinking, applying cosmetics, inserting and removing contact lenses, storing food and utensils
- Cover open wounds, Transport biohazards in leak-proof containers
- Decontaminate waste, work surfaces daily
wash hands (beginning, soiled, glove removal, leaving)
Blunt-end needles if possible (no bending, recapping)
Discard immediately,
Separate contaminated and non-,
puncture-proof waste containers
Mechanical pipetting devices
* Discharge liquid down side of container
* as close as possible to contents
* Never blow
Sterilization decontamination disinfection
Sterilization
* Destruction of all microorganisms, including
spores
Sterilization of materials prior to use * Animal care/surgeries - Cell-culture
Disinfection
* Destruction of microorganisms – may not kill spores
Decontamination
* Destruction or reduction of pathogens to safe level
Autoclaves
- Contact with heated steam at high pressures results in the coagulation of proteins
- Effective conditions must be met and documented
- Validation
- Verification
- For heat and moisture-stable
material
Chemicals (solvents, corrosives) Radioactive materials Bleach and other chlorinated products Plastic and glass not rated for autoclave use
validation +
verification
validation:
Biological Indicators
* Use biological indicators, e.g. Geobacillus stearothermophilus, regularly to prove that the cycle in use is effective
Temperature Sensitive Tape
verification is routine to make sure all good
How to transport biohazardous materials
Use secondary containers to contain potential spillage
Routes of entry
Skin Absorption
Inhalation
Injection
Ingestion
Skin absorption & ***inhalation
common in a lab setting
How many hazard classes are there in WHMIS 2015 for Physical Hazards and Health Hazards?
Physical Hazards: 19 Classes, Health Hazards: 12 Classes
What do pictograms in WHMIS 2015 represent?
They represent various hazard classes. Note: WHMIS 2015 pictograms may have more than one class.
Define the term “Flash Point.”
The lowest temperature at which a liquid produces enough vapour to ignite in the presence of a source of ignition.
lowest flash point -> risk of burning
Describe what pyrophoric substances are and which class
Pyrophoric substances are those that ignite instantly when exposed to air.
physical hazard -> flammables
