Unit 2 Flashcards
Hazard
(any sources of potential damage, harm, etc)
any sources of potential damage, harm, or adverse health effects on something or someone
Risk
the chance or probability that a person will be harmed
the chance or probability that a person will be harmed or experience an adverse health effect if exposed to a hazards
Route of entry (4) of hazards
Hazards’ entry route
Inhalation, absorption, ingestion, injection
What type of inhalation hazards?
Biogical inhalation hazards: airborne pathogens, viruses, toxin, spores, fungi
Chemical inhalation hazards: gases, vapours, aerosol
What is best control of hazards on injection hazards?
Engineering controls
What tools use for Hazard of identification?
SDSs(safety data sheet)
Review of precesures
Review of inspection and incident reports
Equipment operating manual
Maintenance report
Literature reviews
Hierarchy of control of hazards
Engineering controls-most effective measures
Administrative controls
PPE controls -the last line of defence
How many step of Hazard assessment ?
5step
- List the critical steps
- Identify all equipment and procedures
- Identify potential sources of hazards
- Implement hazard controls - use the hierarchy
- Verify the effectiveness of controls
Risk assessment parameters
- risk classification
Probability
Severity
Frequency
What level of risk is acceptable ?
Low risk
Low Risk -acceptable, no further controls are required, may continue
Medium Risk - unacceptable further control needs may continue for a limited period
High Risk - unacceptable further control needs, work stop immediately
Never gonna be 0 risk-always have risk in lab
Good lab safety practices
Before working the lab
- Emergency response procedures
- Know escape route and althernate route
- Know the location of emergency equipment
Good lab safety practices
While working the lab
- Wear PPE appropriate
- No food
- No unknown(unauthorized) person
Good lab safety practices
Before leaving the lab
- Clean up areas equipment surfaces
- Leave PPE in the lab
- Hand washing
Example of Biological hazard
8things
Biological Hazards
Bacteria, viruses, fungi, parasites, infectious materials(body fluid, blood, cell lines), prions, vector-burned pathogens, microbial toxins
Bacteria; single celled organisms (E.Coli, salmonella, streptococcus) can live within or outside a host.
Viruses; infective agent (hepatitis B, HIV-1, mumps) capable of copying itself, but requires a host
Fungi; spore producing organisms (yeasts, rust, molds)
Parasites; organism which lives within the host, depriving it of nutrients (roundworms, toxoplasma gondii)
Infectious material (blood and body fluid, cell lines)
Prions; pathogenic agents that are transmissible. Effects prion proteins in the brain
Vector-borne pathogens; infection transmitted from animal to human (malaria from mosquitoes)
Risk Groups from Canadian biosafety standard
4
Risk Group 1 - low individual risk, low community risk; containment Level 1
Risk Group 2 -moderate individual risk, low community risk; containment Level 2
Risk Group 3 -high individual risk, low community risk; containment Level 3
Risk Group 4 - high individual risk, high community risk; containment level 4
What risk group and containment level of the majority of clinical and lab?
Rush group 2 containment level 2
How to mitigate risk on containment levels?
Containment level 1: hand washing
Containment level 2: administrative controls
Containment level3: engineering controls
Transmission of biological hazards
How many of The links in the chain?
6 infectious agent - reservoir - portal of exit - mode of transmission - portal of entry - susceptible host
How to break the link
Infectious agent - sterilization disinfection
Reservoir / engineering controls
Portal of exit /hand hygiene
Mode of transmission - engineering control ,hand hygiene
Portal of Entry - hand hygiene, PPE
Susceptible host - treatment, immunization
Biological Aerosols
Respiratory exposure to airborne infectious agents is dependent on
The type of infectious agent
The size of the infectious particles
The concentration of infectious agents in the aerosol
The persistence of the aerosol
The length of exposure time
What do Microorganisms need to grow? 6
Nutrition
Oxygen
Moisture
Temperature 37C
Darkness
Neutral pH7
Pathogen
an organism that causes infection
Communicable disease:
an infection that spreads from person to person
Nosocomial infection
hospital-acquired infection resulting from contact with infected patients, employees, visitors or contaminated equipment
Opportunistic infection
results from a defective immune svstem that cannot defend the body from pathogens normally found in the environment
Normal flora or resident
bacteria that normally exist on our body
• On the skin, it resides and grows in the epidermis and deeper layers of the skin known as the dermis
• Difficult to remove from the skin
Transient flora
picked up bacteria during daily activity can be pathogenic
• Lives and grows on the superficial skin layers, or epidermis
• Picked up on the hands through daily activities
• Often pathogenic, but because it is attached loosely to the skin, it is removed easily with handwashing or by applying an alcohol-based hand rub
Fomites
inanimate objects that can carry and transmit infectious agents
• Bed linens, contaminated equipment, telephones, water fountains
Means of infection (8)
Inhalation
Absorption
Ingestion
Percutaneous
Permucosol
People
Contaminated objects
Venipunctures
How to remove or reduce microorganisms?
Decontamination
Disinfection
Sterilization
What requires for autoclaves?
(5)
Time 15mins or more
Temperature 121C
Pressure 15PSI
Contact
Moisture content
Biological indicator for sterilization
What advantage and disadvantage?
Geobaillus stearothermophilhs uses steam
Bacillus atrophaeus uses dry heat
A: Specific temperature and time
D: Test materials must be incubated in 24-48 hours
What is the difference between disinfection and sterilization and discontamination?
All of goal : reduce or remove micro organisms
Decontamination - reasonable free of microorganisms
Disinfection - much less lethal to infectious materials than sterilization
Sterilization : full of elimination
Decontamination - “process by which materials and surfaces are rendered safe to handle and reasonably free of microorganisms, toxins, or prions; this may be accomplished through disinfection, inactivation, or sterilization
Sterilization - a process “that completely eliminates all living microorganisms, including bacterial spores”
• Usually though use of an autoclave, dry heat, boiling or incineration
Disinfection: “that eliminates most forms of living microorganisms; disinfection is much less lethal to infectious material than sterilization”
Bleach; 1/10 for spills, 1/100 for wiping
Isopropyl alcohol; 70% or 95%
Combination products; alcohol/quaternary ammonium, hydrogen peroxide
What is Universal precautions and Standard precautions?
Universal precautions ( 1985) - procedures for dealing with patients and test specimens based on the assumption that all patients may be positive for bloodborne pathogens
Standard precautions (1996) - used with all patients all the time
A safety guidelines designed to protect patients and healthcare workers
All patients and all body fluids, any substance, organs and unfixed tissues be regarded as potentially infectious.
• 3 transmission based precautions - airborne, droplet, contact
Use PPE
Routine practices - based on all laboratory samples being potentially infectious
What BSCs?
Biological safety cabinet
• Designed for partial primary containment for BIOLOGICAL hazards
• Air supply and removal
• Minimizes the escape or aerosols
• HEPA filter
• Certified on initial installation, when moved/repaired, annually
• Routine maintenance - wipe down, drip tray, clean the lights
Step of proper use of BSCs
Start up
Working
Completion
Start up considerations
A BSC is certified for use by one person at a time(no 2peole)
Working in the BSC
Avoid excessive movement of hands and arms through the front opening
Completion of work in the BSC
Allow enough time for the air in the BSC to filler
