Lectures 4 & 5 Flashcards
What is the hierarchy of controls?
-Engineering: most effective (designing equipment)
-Administrative: depends on adherence to rules (training procedures)
-PPE: last line of defence (gloves, masks, etc.)
What is decontamination?
Describes the procedures that remove contamination by killing microorganisms with the goal of making items safe for use or disposal.
What is disinfection?
-A type of decontamination that destroys specific types of organisms, but not all spores
-Usually done with chemicals
What is sterilization/
The complete removal of all microorganisms by chemical OR physical means
3 uses of chemical disinfectants for decontamination:
-surfaces and equipment that can’t be autoclaved
-spills of biohazardous material
-in discard jars and pipette jars
What is the most common disinfectant?
Diluted sodium hypochlorite (aka bleach, 5.25%)
What is the more effective concentration of isopropyl alcohol?
70%
What should you always do before using chemical disinfectants?
Check labels for proper use instructions and use appropriate PPE
5 ways to accomplish sterilization:
- Steam autoclaves
- Gas sterilizers
- Filtration
- Dry heat
- Boiling
The 5 aspects of autoclave sterilization:
- Pressure
- Temperature
- Moisture content
- Time
- Contact
What are the effective operating parameters for gravity displacement steam autoclaves?
Temperature: 121C
Pressure: 15 psi
Time: minimum 15 minutes
Describe the proper use of an autoclave:
-Items loaded into metal or heat-resistant plastic containers
-Avoid stacking/crowding items
-Remove lids from lidded containers
-Autoclave should be located near to the lab
What are indicators used for in autoclaves?
Indicators are used to determine if you’ve achieved successful decontamination, can be biological or chemical
What is a biological indicator?
-A test system containing viable bacteria with a defined resistance to a specified sterilization process
-After sterilization the bacteria must be incubated; if no bacteria grow, it was successful.
What is a chemical indicator?
A test system that changes in response to certain predefined variables, often changing from one colour to another to indicate success.
What is ergonomics?
The science of designing work with the worker in mind, an integral part of work efficiency and worker well-being.
Name 7 results of improper ergonomics:
- Musculoskeletal Disorders (MSDs)
- Fatigue
- Repetitive motion injuries
- Monotony (increased errors and accidents)
- Biochemical stresses that create strains, aches, injuries
- Eye strain from screens
- Lowered morale (mental health issues)
What are MSDs?
Disorders of muscles, tendons, and nerves caused gradually by overuse that become hazardous due to continual repetition, forceful manner, speed of the movements, and lack of recovery time
What are the 3 common risk factors for MSDs?
- Force: amount of compression/tension/shear inside or applied to the body (e.x. wrists on a desk while typing
- Posture: deviating from neutral posture causes stress on the body (e.x. bending, twisting)
- Time: frequency, duration, repetition of tasks/movements
Name 5 ergonomic considerations and solutions:
- Adjustable work surfaces
- Variation of tasks and movements
- Using carts to move heavy materials
- Design and position of screens
- Air quality (temperature, humidity)
What are the dangers and precautions associated with compressed gas?
- Dangers: can explode if heated, high pressure gas streams can puncture skin, can make a toxic, flammable, or corrosive atmosphere
- Precautions: secure cylinders upright to architectural support, store away from the lab, transport using 4-wheeled hand trucks or dollies
What are the dangers and precautions associated with cryogenics?
- Dangers: burns and tissue damage, embrittlement of materials, pressure buildup in container
- Precautions: wear PPE, no jewelry, be aware of drops of liquid nitrogen remaining on containers, wear eye protection until pressure has been released
What are the dangers and precautions associated with electrical hazards?
- Dangers: potential ignition source, can be fatal
- Precautions: avoid using extension cords and multiple adapters, use outlets with grounding connection, pull plugs not cords, keep cords away from high traffic areas
What are the dangers associated with ionizing radiation, and where does it come from?
- Sources: x-rays, gamma rays, alpha particles, beta particles, neutrons
- Dangerous to: bone marrow, breasts, thyroid, lungs, digestive system, fetuses
What is non-ionizing radiation?
radiation that does not ionize atoms or molecules, and includes: lasers, microwaves, and UV radiation
What are the dangers and precautions associated with lasers?
- Dangers: eye injury, fire
- Precautions: don’t look directly at the laser, wear appropriate eye protection
What are the dangers and precautions associated with ultraviolet lamps?
- Dangers: unless exposure is extreme, most injuries are transitory
- Precautions: goggles or face shields with lens filters, turn off UV lights when not needed
What are the dangers and precautions associated with heat exposure?
- Dangers: burns, hyperthermia
- Precautions: heat-resistant gloves, allow autoclave to exhaust steam before opening, take breaks and drink water if working in a warm environment
What are the dangers and precautions associated with cold exposure?
- Dangers: burns, hypothermia
- Precautions: insulating gloves, warm clothing if working in a cold environment
What are the dangers and precautions associated with noise?
- Dangers: hearing loss, aural pain, disruption of sleep or relaxation, interference with communication
- Precautions: evaluate equipment noise levels before purchasing, place noise away from workstations if possible, maintain equipment
What are the dangers and precautions associated with pressure?
- Dangers: pressure differences between lab apparatus and atmospheric pressure can cause glassware to shatter, can result from rapid temperature changes or chemical reactions in sealed containers
- Precautions: allow containers to return to atmospheric pressure//temperature before opening, wear PPE
Name the four types of symptoms caused by excessive stress:
- Physical (insomnia, high blood pressure)
- Behavioural (irritability, withdrawal from others)
- Emotional (hostility, anxiety, daydreaming)
- Mental
5 ways to control/reduce stress:
- Self-renewal activities (vacations, work-life balance)
- General health practices (proper nutrition, sleep, exercise)
- Counselling
- Communicate with supervisor(s)
- Treatment as prescribed by a physician
The 4 basics of preventing abuse/bullying:
- Reporting system
- Early conflict resolution
- Zero tolerance for disruptive behaviour
- Well designed workplace: escape route, telephone, alarm initiator
What are reproductive risks?
Hazards that impact the ability to have healthy children
Reproductive risks to men:
- reducing sperm production
- changing sperm shape
- altering sperm chromosomes
- impacting sexual performance
Reproductive risks to women:
- menstrual cycle effects
- Infertility or sub-fertility
- miscarriage and stillbirths
- birth defects
What are reproductive effects?
Problems in the reproductive process caused by a substance
What is a teratogen?
A substance that can cause birth defects
What is embryotoxicity?
The ability of a substance to cause harm to the embryo
What is fetotoxicity?
The ability of a substance to cause harm to the fetus
What is mutagenicity?
The ability to cause changes in the DNA of cells
Employer precautions for reproductive hazards:
Identifying hazards, communicating the hazards, control the the hazard through engineering, administrative, and personal controls
Reducing risks during pregnancy:
-notify supervisor
-consult SDS
-modified or changed tasks
What is resolution (in microscopy)?
Indicates how small and how close individual objects can be and still be recognized as distinct; the more detail seen, the higher the resolution
What is magnification?
-units are in terms of diameters, so if an object is magnified 100x, the diameter is magnified to 100x its original size
-total magnification=objective x occular
What is the numerical aperture?
