Safety Guidelines Flashcards
What are the categories of hazards?
chemical
biological
physical
ergonomic
psychological
a commonly used approach to identify and control hazards is called a
TASK HAZARD ANALYSIS
steps of a task hazard analysis
- list critical (major) steps of task
- identify potential hazards at each step
- review available control measures
- verify the task, ensuring the requirements for proper procedures and use of all required controls
- if current control measures are not adequate, identify more appropriate controls
a risk assessment should take into consideration these three things:
severity
probability
frequency
hierarchy of controls
engineering (substitution)
administrative (adherence)
personal controls (last line)
T or F. Administrative controls are considered the most effective
F! engineering controls are considered most effective
what is due diligence?
doing everything reasonable to protect the health and safety of workers
- employers shall take all reasonable precautions, under the particular circumstances, to prevent injuries/accidents in the workplace
Management is responsible to:
- provide appropriate resources for safe work
- conduct accident investigations
- orient and train all staff
- identify hazards and advise employees accordingly
- take corrective action for identified safety hazards
- participate in program development and implementation
employees are responsible to:
- report hazards
- report accidents and incidents
- follow rules
- undergo training
- participate in program development and implementation
T or F. Health and safety legislation is primarily a provincial jurisdiction in Canada
T! each province and territory have its own occupational health and safety act and associated regulatory agency
what are the three major elements of WHMIS 2015?
safety data sheets
labels
training
the most important element of WHMIS legislation is
training
this control includes actions, items, or equipment designed to reduce harmful exposures
engineering controls
- isolation of hazard
- guarding to prevent contact between worker and moving parts
- ventilation
- safety containment
this control is composed of actions that can be taken by administrators of an organization to reduce employee exposure to hazards
administrative controls
the major components of an emergency preparedness plan are:
- identification of potential emergency situations
- development of emergency response procedures and contingency plans
- communication protocols uring emergencies, both internal and external communications
- training of staff on emergency response procedures, including periodic drills
what is a hazard?
anything that present the potential to cause injury or illness to a lab worker
what is risk?
takes into account the real possibility that there will be an exposure as well as the extent of damage an exposure will cause
T or F. Not all hazards are risks
T! but all risks are derived from hazards; first step is always ID of hazards
the chance or probability that the hazard will cause an injury or illness
risk
steps of a job hazard assessment
- list critical/major steps of the job
- identify all equipment to be used and procedures to be performed
- identify potential hazards at each step (include all types of hazards)
- review available control measures (hierarchy of controls)
- verify effectiveness of controls
who publishes the Canadian biosafety standard and Canadian biosafety handbook?
PHAC
risk group 1
low indiv risk, low community risk
risk group 2
moderate indiv risk, low community risk
risk group 3
high indiv risk, low community risk
risk group 4
high indiv risk, high community risk
this contains a list of human pathogens classified according to risk group
human pathogens and toxins act
this is the first step in determining the appropriate containment level for handling and storing biohazards
classification according to risk group
T or F. For the most part, risk group and containment level are the same
T! risk group 2 = containment 2
EXCEPTIONS = HIV, HTLV-1, Mycobacterium tuberculosis complex (MTBC) are risk group 3 stored and handled at containment level 2 w specific additional biosafety requirements
this describes the minimum physical features and operational practices needed for the safe handling and storage within an identified area such as a laboratory
containment levels
this provides a detailed description of the four containment levels used in Canada
Canadian Biosafety Standard
decontamination
term used to describe procedures that remove contamination by killing microorganisms, rendering the items safe for disposal or use
disinfection
means of decontamination and refers to the destruction of specific types of organisms but not all spores usually by chemical means
sterilization
the complete destruction or removal of all microorganisms by chemical or physical means, usually to provide sterile items for use
the three principal methods of decontamination in general use for decontamination lab waste
- autoclave
- chemical disinfectants
- incineration
methods used for decontamination of reusable lab wares are:
- autoclave
- chemical disinfectants
how is sterilization accomplished?
- autoclaves
- gas sterilizers (ethylene oxide)
- filtration
- dry heat
- boiling
autoclaves function efficiently through proper control of:
- pressure
- temperature
- moisture
- time
- contact
effective operating parameters for gravity displacement steam autoclaves
temp = 121C
pressure = 103.4 kPa or 15 psi
time = 30-60 mins
** displacement is dependent upon proper loading of adequate steam penetration **
recommended test microorganisms used as bio-indicators for autoclaves
Geobacillus stearothermophilus spores (sterilizers that use steam, H2O2 gas plasma or peracetic acid as well as immediate use steam sterilizers
Bacillus atrophaeus (formerly B. subtilis) spores for sterilizers that use dry heat or ethylene oxide
types of chemical indicators used for sterilizers
- tapes = indicate if air is removed, but are not sensitive to time and temp
- glass tubes containing pellets = melt at 121C; independent of steam and partially dependent on time
recommended conctn of alcohol as a disinfectant
70%
more effective than 95%!
for highly concentrated spills of biological agents, this can be useful because it has low corrosivity, acts quickly, and is active against a wide variety of microorganisms
peroxyacetic acid mixed with hydrogen peroxide
Lagging indicators
measure the occurrence and frequency of events that occurred in the past, such as the number or rate of injuries, illnesses, and fatalities
Leading indicators
proactive and preventive measures that can shed light about the effectiveness of safety and health activities and reveal potential problems in a safety and health program (Occupational Safety & Health Admin)
Threshold Limit Values
highest level at which large percentage of healthy workers can be exposed to a substance without ill effects
- allowable levels of exposure adopted by Canadian provinces
prions susceptibility & effective disinfectants
extremely resistant!
chemical disinfectants (high conctn of sodium hypochlorite or heated strong solutions of sodium hydroxide)
protozoal oocysts susceptibility & effective disinfectants
highly resistant
amm hydroxide, high conctn halogens, halogenated phenols
bacterial endospores susceptibility & effective disinfectants
highly resistant
some acids, aldehyde, high conctn halogens, some peroxygen compounds, some phenols
mycobacteria susceptibility & effective disinfectants
resistant
alcs, aldehydes some alkalis, halogens, some peroxygen, some phenols
non-env viruses susceptibility & effective disinfectants
aldehydes, halogens, peroxygen compoounds
susceptible organisms
fungal spores, GNB, env viruses, GPB
- use alcs, aldehydes, alkalies, etc. *
highly susceptible organisms
mycoplasma
T or F. Incinerators are rarely under the control of the lab
T!
a term used to describe a set of procedures for dealing w patients and test specimens, based on the assumption that all patients may be positive for blood-borne pathogens such as hepatitis and HIV
universal precautions (1985)
Body Substance Isolation procedures
1987
same as universal precautions (same barrier precautions for all moist body substances not just those associated with transmission of HIV and Hep)
Standard Precautions
1996
airborne, droplet, contact precautions
Post-exposure follow-up plan
- timely response (ideally within 2 hrs of exposure)
- documentation
- ID of source
- testing of source patient’s blood/bodily substance
- testing of employee’s blood
- counselling
the number and size of HEPA filters used depends upon …
type and size of bio safety cabinet used
- standards based on filter’s efficiency of removing particles of 0.3 um (most difficult size to filter)
when are HEPA filters tested and certified?
upon installation
when moved/repaired
annually
T or F. The use of UV light to disinfect BSC is highly recommended
F! not recommended due to limited effectiveness at disinfecting interior surfaces of BSC
should only be used as a secondary method of maintaining the disinfected status of a BSC
what disinfectant is included in a bio spill kit?
small quantities, made fresh daily if phenolics or hypochlorites
WEEKLY if activated glutaraldehyde
T or F. Supplier labels need to both be in French and English
T (either on one label or two separate labels) and no longer need hatched borders
What are supplier labels required to have?
product identifier (brand name, chemical name, etc.)
ID of supplier,
pictogram,
signal word (+ severity),
hazard statements describing nature of hazard,
precautionary statements,
supplemental info (some hazards)
Two choices for signal words
warning and danger (higher risk hazards)
T or F. Supplier labels on products of 100 mL or less do not need to have hazard or precautionary statements on the label
T! All other requirements apply though
what is required on a workplace label?
at least:
product name
safe handling precautions
reference to SDS
consult provincial requirements
When is the SDS updated?
anytime supplier becomes aware of any significant new data that impacts validity of contents
LD50
LETHAL DOSE 50
quantity of substance that when administered by a particular route, is expected to CAUSE DEATH OF 50% OF A DEFINED POPULATION
(mg/g per kg)
LC50
lethal concentration 50
conctn of substance in air that, when administered over specified period of time is expected to cause death of 50% of defined popln
(ppm or mg/m^3)
the max limit of exposure to an air contaminant
exposure limit
8-hr TWA (time-weighted average)
concentration in air, when averaged over an 8-hr work shift represents the conditions under which it is believed that nearly all workers may be repeatedly exposed day after day w/out adverse health effects
STEL
short-term exposure limit
concentration in air, when averaged over a 15min period represents conditions under which is believed that nearly all workers may be repeatedly exposed day after day, up to a max of 4 times per day without adverse effects
ceiling limit
the concentration in air which should never be exceeded and is applied to chemicals w acute toxic effects
the most common route of entry for hazards for lab workers
resp system
the only A1 carcinogen associated with the lab
benzene (mostly phased out)
A2 carcinogens in lab
ethylene oxide and formaldehyde
CARCINOGENS (5)
A1 - confirmed human carcinogen
A2 - suspected
A3 - animal carcinogen
A4 - not classifiable as human carcinogen
A5 - not suspected as human carcinogen
flammable vs combustible materials
flammable = can burn at RT
combustible = must first be heated before they can burn
fire triangle
FUEL
OXYGEN
HEAT
what is the flash point?
minimum temp at which a liquid gives off enough vapour to ignite in the presence of a source of ignition – the lower the fp the greater the risk of fire
ignition or auto-ignition temperature
temp at which a material will ignite even in the absence of source of ignition
flammable or explosive limits
specify range of conctns of fuel in air that will burn/explode in presence of ignition source
below lower flammable limit = fuel too low to ignite
above upper limit = oxygen too low
oxidizing materials (5)
- provides source of oxygen
- can cause fires if contact w flammable and combustible materials (even in absence of O2 or ignition source)
- can increase speed/intensity of fire
- can cause non-combustibles to burn rapidly
- can react w other chemicals = liberate toxic gases
organic peroxides
special oxidizers
provide both source of fuel and oxygen = risk of explosion
ex: benzoyl peroxide
corrosive materials include:
acids
bases (caustics, alkalis)
others with corrosive properties
T or F. We must use dry forms of oxidizers
F! UNSAFE; use solutions to avoid release of dusts
T or F. The closer the pH is to 7, the more corrosive the substance
F! The farther away from 7
How long should we rinse eyes for ?
15 minutes
T or F. We should always store acids with bases to neutralize
F! store acids separate from bases
Where should we store glacial acetic acid?
flammables
- flash pt of 39C
- common mistake = store w acids
We should store liquids (below/above) eye level?
BELOW
what are insidious hazards?
progress imperceptibly but harmfully (may not intitially be hazardous, but progress to possess harmful effects overtime)
= ether, mercury, perchloric acid, picric acid, sodium azide
how to clean up: solvents
spill control pillows
activated charcoal
how to clean up: acids
spill control pillows
acid neutralizer
how to clean up: caustics (bases)
spill control pillows
caustic neutralizer
how to clean up: “other liquids”
spill control pillows
how to clean up: mercury
mercury vacuum or mercury spill kit
what are cryogenic fluids?
liquefied gases at very low temps (below - 73.3C)
ex: liquid nitrogen
radiation that has the ability to displace an electron from an atom or molecule = producing ions
ionizing radiation
three major types of non-ionizing radiation found in the lab:
lasers
microwaves
UV
major danger of lasers to worker
eye injury
- cornea and lens can focus parallel light beams and burn retina
laser class I
enclosed beam/low power (unlikely to cause eye injury) = laser printers, bar code scanners, disc players
laser class II
low power lasers (<1 mW)
- staring could damage eyes
- classroom pointers
laser class IIIA
1-5 mW
- staring directly or through lenses is hazardous
- some pointers, therapeutic lasers
laser class IIIB
5-500 mW
- instant injury to eyes from direct or specularly reflected beam
- light show lasers, engraving lasers, some medical lasers
laser class IV
> 500 mW
- instant injury to eyes, skin
- can cause fires
- surgical lasers, computer controlled cutting lasers
the principle hazard associated with microwaves is …
the heating of tissue
UV wavelength
180 to 390nm
three main factors determining risk of musculoskeletal injuries
awkward postures/movements
repetitive movements
amount of force applied
why should the vertical position of microscope eyepieces be set a little high for comfort?
this forces workers to maintain head upright = prevent strain on neck
factors that may contribute to excessive stress:
organizational factors, environmental factors, personal factors
factors that determine if an infection will occur as a result to aerosol exposure:
- viability of biohazard
- conctn of particles
- size of particles
- persistence of aerosols
- susceptibility of individual person
the most commonly used disinfectant in the lab
bleach
- sodium hypochlorite
- 1/10 dilution for spill control
standard precautions are now called:
routine practices and additional precautions (Canada, 1999)
T or F. A current of as little as 25 milliamperes from a 100 volt power source can be fatal
T!
sources of ionizing radiation
x-rays
gamma
alpha particles
beta
neutrons
high penetrating radiation types
x-rays
gamma
high-energy beta particles
(external exposures are of concern)
internal exposure hazards
alpha (most damaging to human tissues when absorbed)
beta
gamma
the most penetrating ionizing radiation
gamma
technostress
stress caused by rapidly changing technology and reliance on technology-based equipment
teratogen
substance that can cause birth defects
- can be fetotoxic or embryotoxic
embryotoxicity
ability of substance to cause harm to embryo
fetotoxicty
ability of substance to be harmful to fetus (eg: malformation, altered growth in utero death)
mutagenicity
ability to cause changes in DNA of cells
dibromochloropropane
lower sperm count
lead
lower sperm count
abnormal shape
altered sperm transfer
altered hormones/sexual performance
toluenediamine and dinitrotoluene
lower sperm count
ethylene dibromide
lower sperm count, abnormal sperm shape and transfer
ethylene glycol monoethyl ether
lower sperm count
perchloroethylene
abnormal sperm shape
mercury vapour
altered hormone/performance
radiation
lower count
abnormal shape
altered sperm transfer
altered hormones/performance
carbon disulfide
altered hormones/performance
bromine vapour
lower count
abnormal shape and transfer
2,4-dichlorophenoxyacetic acid
abnormal shape and transfer
general ventilation
AKA dilution ventilation
- dilution of inside air with a supply of outdoor air
general ventilation serves to (4)
- maintain comfort levels (temp, humidity, etc.)
- dilute indoor air contaminants
- provide make-up air to replace air being exhausted by local vent devices
- provide control of environmental conditions for specialized applications (ex: clean rooms)
two basic components of general vent system
air supply and air exhaust
HVAC system
heating
vent
air conditioning
how can air from a lab be removed?
either via local exhaust device (fume hoods; air released outdoors) OR via air returns (some of air is mixed w outside air and recirculated within HVAC)
effectiveness of general ventilation system is dependent on:
- volume of fresh air
- purity of air
- temp and humidity levels
- proximity of air supply sources to air return grilles and local exhaust devices (don’t want to “short circuit”)
- air distribution efficiency
- balancing of ventilation to maintain neg pressure (more air exhausted than supplied to room to prevent c contamination of adjacent areas)
- maintenance of system
- renovations and other functional changes within building
T or F. General ventilation is the preferred means of controlling exposure to airborne substances
F! better achieved by way of local exhaust ventilation
common local exhaust vent devices
chemical fume hoods
canopy hoods
slotted hoods
BSCs
direct connections
what is a local exhaust vent system
captures and removes contaminants or excess heat from pt of release
preferred location of fan of a fume hood
end of the duct
auxillary air hoods and variable air volume hoods
designed to conserve energy
AA = lacks reliability
VAV = dependable
ductless fume hoods
self-contained devices which filter air from hood and return it to lab
these are designed to capture heat or contaminants from machines or processes
canopy hoods
why can’t we use canopy hoods as a substitute for chemical fume hoods
draw contaminated air through breathing zone of user
draw upwards; less effective in capturing heavy vapours & aerosols
provide less enclosure than a chemical fume hood = more vulnerable to air turbulence
fail to provide adequate suction beyond a few cm away from hood opening
these capture emissions at the source
direct connections
transient emissions
AKA fugitive emissions
air pollutants released into indoor environment and usually characterized by the presence of odours that sometimes disappear as mysteriously as they appear
humidity range
20-60%
source of transient emissions
- inappropriate lab practices
- building system malfunctions
- renovation, construction or maintenance activities
- outdoor pollution sources
two most common errors workers make with respect to PPE
- not wearing PPE when indicated
- self-contamination during removal of PPE
T or F. facial protection is generally the last PPE removed
T!
T or F. Face shields are a substitute for eye protection
F!
this document prescribes the baseline standards for regular emergency eyewash and shower equipment
ANSI
American national standards institute
the most critical of the emergency wash devices
eyewash
what are drench hoses?
provides a controlled flow of water to a portion of body at low velocity (non-injurious)
which classes of fire does carbon dioxide extinguish?
B,C
- dissipates quickly; hot fuel may re-ignite
which classes of fire does ABC dry chemical extinguish?
A,B,C
- most versatile, but leaves mildly corrosive powder which must be cleaned
which classes of fire does water extinguish?
A
- dangerous if used in many lab situations (ex: electrical equipment or on water-reactive chemicals)
which classes of fire does class D dry chemical extinguish?
D
- metal fires ONLY
T or F. Fire blankets are always recommended
F!
- emergency blankets are used to keep injured person warm and in order to prevent shock
T or F. During a needlestick injury, one must apply alcohol-based hand sanitizer to clean their injury
F! wash with soap and water
do NOT use chemical cleansers, antiseptics or disinfectants
AED
automatic external defibrillator
- portable device
- automatically diagnoses certain types of cardiac arrhythmias (applies small electrical charge to heart muscle to enable heart to resume normal rhythm
which type of tubes should we avoid
cellulose nitrate tubes
- highly flammable
- distort w age and can explode in autoclave
water baths precautions
- prevent microbial contamination by adding disinfectant to water bath (phenolic detergent suggested)
- do not use sodium azide = explosion hazard
- unplug before filling or emptying
what type of pipette to use with biohazards?
pipettes plugged w cotton
why do we expel liquids to the side of tubes slowly when pipetting?
to avoid aerosol formation via splashing
what do we routinely decontaminate cryostats with?
100% alcohol
- tuberculocidal if suspected tuberculosis
- sodium hydroxide of CJD suspected
T or F. Defrost and decontaminate cryostats monthly
F! WEEKLY
T or F. Disposal of biological and radioactive agents are provincially and municipally regulated
F federally; everything else = municipal and provincial legislation
T or F. Live vaccines are considered biomedical waste
F!
what is biosecurity?
designed to prevent intentional or deliberate acts
- biosafety = unintentional or accidental acts
hazards that need emergency wash devices
- corrosive materials that can damage eyes or skin
- toxic materials that can be absorbed through eyes and skin
- open source nuclear substances
- infectious substances that can be absorbed through eyes or skin
- released dusts or projectiles
an emergency eyewash should be located…
within ten seconds walking distance of eye hazard
tepid water temp
16 - 38C
T or F. Before using an emergency shower, you should remove your outer clothing
F! remove while under shower
T or F. It is required that emergency wash devices have a drain
F!
this substance can leave behind explosive crystals if it condenses in the lining of a fume hood duct
perchloric acid
this can combine with copper in a drain which results in a potentially explosive compound
sodium azide
