Lectures 1-3 Flashcards
Universal precautions:
Set of precautions that assume all patients are positive for blood borne pathogens (1985)
Body substance isolation procedures:
Same as universal precautions, but applies to all body fluids (1987)
Five steps of standard precautions:
- Education (training for safe handling)
- Hand washing
- PPE
- Decontaminate surfaces
- Safe handling/disposal of contaminated materials
Isolation precautions (contact):
-C. diff, norovirous
-gown + gloves
Isolation precautions (droplet):
> 5 microns
-mumps, influenza
-mask, goggles, face shield
Isolation precautions (airborne):
< 5 microns
-tuberculosis, chicken pox
-gown, gloves, goggles, N95
Donning PPE order:
-HH
-Gown
-Mask
-Eyewear
-Gloves
Doffing PPE order:
-Gloves
-Gown
-HH
-Eyewear
-Mask
-HH
Proper glove removal:
Glove-to-glove
Skin-to-skin
Small spills:
< 10mL
-Cover with paper towels
-Pour disinfectant from outside in
-Wait 30 min
-Remove towels with forceps
-Repeat
Large spills:
> 10mL
-Hold breath and move away
-Inform others
-Wait 10-30 min
-Follow small spill procedure
Spills in centrifuge:
-Turn off
-Don PPE
-Wait 30 min
-Remove all broken items & place in disinfectant
-Place unbroken specimens in disinfectant
-Disinfect bowl
-Dispose of cloths
-Remove sealed bucket to BSC (unless something broke, then autoclave it all)
Spills in a BSC:
-Fan on
-Pour disinfectant to dilute 10 fold
-Wait 30 min
Spill kits contain:
-Additional PPE
-Towels + spill sock
-Container for disposal of contaminated spill kit items
-Forceps
-Disinfectant
-Autoclavable dust pan + brush
-Heavy duty polyethylene bags
-Activated charcoal
-Acid + caustic neutralizers
-Mercury vacuum/spill kit
Leaking specimens:
-Rejected unless irretrievable
-Inform others
-Don PPE
-Place in tray in large ziplock & move to BSC
-Perform small spill procedure where specimen was
-In BSC use paster pipette to transfer specimen to clean container
-If requisition is contaminated place in plastic until copied
-After transfer flood tray + contents with disinfectant for several hours then autoclave
General chemical storage:
-Keep secure
-Minimize quantities kept in lab
-Use unbreakable/shatterproof containers
-Store hazard liquids where spills can be contained
-Keep large containers on low shelves
-Store liquids below eye level
-Separate chemicals by reactivity class and flammability
-Keep current inventory list
Classes of fire:
-Class A: combustible solids (paper, wood)
-Class B: liquid fuels (organic solvents, oil)
-Class C: electrical
-Class D: flammable metals (Na, K)
Types of fire extinguishers:
-Carbon dioxide: class B+C
-A-B-C dry chemical: class A+B+C
-Water: class A
-Class D dry chemical: class D
PASS technique:
Pull
Aim
Squeeze
Sweep
Emergency fire procedures:
-Alert others
-Call fire department/institutional emergency line
-Evacuate lab and close door
-Pull nearest alarm
-Exit building
-If exit not possible enter designated refuge area, close door, place wet towels around openings and inform someone of your location
-Only use extinguishers on small fires
-Never use fire blanket, only stop drop and roll
Needle stick injuries:
-Clean exposed area with soap + water
-Use eyewash station on mucous membranes
-Avoid chemicals/antiseptics
-Don’t milk wound
-Allow free bleeding then cover lightly
-Identify source/patient/sample code & report to supervisor immediately
-Follow internal procedures
Hand washing technique:
-Wet hands
-Apply soap
-Lather entire hands for 15sec minimum
-Dry hands
-Use paper towel to close tap
-Dispose of paper towel
Four moments of hand hygiene:
- Upon entering patient area
- Immediately before aseptic procedures
- Immediately after exposure risk & glove removal
- Upon leaving
Eye wash procedure:
-Proceed directly to station
-Activate unit
-Hold eyes open & roll back and forth to rinse entire eye
-Flush for minimum 15min
-Flush 1min before removing contact lenses, then flush 15min
-Seek medical treatment
Emergency shower:
-Proceed directly to station
-Activate unit
-Remove clothing
-Flush minimum 15min
-Seek medical treatment
Biohazard waste disposal:
-Large biohazard boxes (brutes): CONTAMINATED NON-SHARPS (visibly soiled gloves, used gauze)
-Sharps containers: CONTAMINATED SHARPS (lancets, used needles)
-Biohazard sharps pail: OTHER CONTAMINATED SHARPS (used glass slides, test tubes) & NON-CONTAMINATED SHARPS (broken glass)
-Regular garbage for NON-CONTAMINATED NON-SHARPS (gloves, paper towel)
Volumetric glassware:
-Measures accurate volumes
-Calibration is a lengthy process
-Costs more than non-calibrated
-Must be high quality, transparent, & free from irregularities/defects
Graduated glassware:
-Piece of glassware with calibrated markings
-Measures approximate liquid volumes
-Poor accuracy compared to volumetric
Reading the meniscus:
-Always read from the bottom
-Determine how many sig figs you have
-always some uncertainty
Blow out:
-Pipettes designed to have the bulb blow out all contained liquid
-Determined by presence of etched rings at top
Volumetric pipettes:
-Deliver a fixed volume by drainage
-Highly accurate
-Usually 1-100mL
Ostwald Folin Pipettes:
-Deliver a fixed volume
-Lower pear-shaped bulb
-Blow out
-Used for viscous fluids (blood, serum)
Serological pipettes:
-Graduated
-Larger orifice
-Drains quickly
-Calibrated from tip to zero
-Less accurate than volumetric & mohr
-Blow out
Mohr pipettes:
-Tip volume is unknown
-Designed to deliver multiple volumes
-Not to be used for a single volume
-Not blow out
Proper pipetting technique:
-Use bulb to draw liquid up past calibration mark
-Quickly replace bulb with finger
-Wipe outside of pipette
-Use finger to slowly drain liquid to set the meniscus
-Drain into receiving container holding receiving container at an angle
-Allow fluid to drain
-Determine if pipette is blow out or not
Cleaning pipettes:
-Place in a container of 10% bleach, tip side up
-Soak minimum 30min
-Rinsed 1-2hrs in tap water
-Rinsed 2-3 times in distilled water
-Dry in hot air oven
Cleaning glassware:
-Can be left to soak overnight in water + detergent until you have time to wash
-Decontaminate prior to cleaning by pre-soaking in 5% bleach
-After washing rinse 4-5 times in tap water then 2-3 times in distilled water
Disposable transfer pipettes:
-Most commonly used transfer pipette
-One piece
-Safe method for liquid transfer
-Sizes vary
-Can be sterile or non-sterile
Automatic pipettes:
-Used for rapid, repetitive measurements of small volumes, usually in micro litres
-You set the volume (within range)
-Uses disposable plastic tips
-No need to wipe (non-wettable tips)
-Most auto-eject tips
-Frequent calibration required
Disadvantages of plastic ware:
-Leaching into solutions
-Some permeability to water vapour
-Absorption of dyes, stains, proteins
-Affected by oxidizing agents
-Some soluble in toluene, chloroform
-Affected by sunlight
-Organic solvents can evaporate through
-Cannot be heated
Polyolefins:
-Used for polyethylene & polypropylene
-Most widely used plastic
-No reaction with most chemicals
-Reacts with strong oxidizers at high temps
Polycarbonate resin:
-Physically strong
-Heat & scratch resistant
-Glass-like transparency
Tygon:
-Clear
-Non-toxic
-Flexible
-Unreactive
-Can be autoclaved
-Plastic tubing
Teflon fluorocarbon resin:
-Resists most chemicals
-Withstands -270-255 degrees C
-Expensive
-Bottles, beakers, cylinders
Polystyrene:
-Vinyl polymer
-Inexpensive
-Mostly disposable
-Second most common
Borosilicate glass:
-High thermal resistance
-Low alkali
-Heat up to 600C
-Shock resistant
-Pyrex, Kimax, Exax, Vycor, Corex
-Beakers, flasks, pipettes
Alumina glass:
-High silicate content
-Chemically strengthened
-Radiation, heat, & acid resistant
-Good precision
-Microscopes, lenses, cuvettes
Acid/Alkali resistant glass:
-Resists corrosion & thermal shock
-Boron free. weaker than borosilicate
-“Soft glass”
-Not resistant to thermal shock
-Not very common
Flint glass:
-Oxides of silicon, Ca, Na
-Clear
-Cheapest
-No heat or thermal shock resistance
-Used for disposability
Low actinic glass:
-Brown or amber
-Stores light-sensitive materials
-Can be any type of glass
Labeling containers:
-Supplier labels (product identifier, initial supplier identifier, pictogram(s), signal word, hazard statements, precautionary statements, supplemental info, easily displayed)
-Workplace labels (required when hazard is transferred, name, safe handling, SDS reference)
Calibration of volumetric glassware:
-Determines exact volume
-Marked in graduations
-Checked against specifications
-Performed by weight with distilled water
Preparing reagents in a volumetric flask:
-Always add chemical to water
-Use solvent to rinse all solute from weighing vessel if solute is solid
-Add liquid solvent to flask to just below neck
-Stopper flask & mix by inversion
-Add solvent with transfer pipette drowse up to calibration mark
-Ensure fluid is at room temp first
Absolute and relative uncertainty:
-Absolute: X plus or minus Y
-Relative: absolute divided by measurement time 100%
Accuracy:
-Closeness to true volume
-Can describe technique
-Can describe glassware
-Lower uncertainty = higher accuracy
Precision:
-Reproducibility
-Technique
-Getting same results from same test = precision
-Glassware (if a pipette always delivers same volume)
-Not necessarily accurate (multiple identical but inaccurate results
