Commonly Encountered Hazards Lecture 4 Flashcards
1
Q
What are Hazardous Materials?
A
Hazardous materials are substances or chemicals that pose a health hazard, a physical hazard, or harm to the environment.
2
Q
What are the Hierarchy of Controls?
A
- Engineering
- Administrative
- Personal Protective Equipment
3
Q
What is the most effective Control?
A
Engineering
4
Q
What is the Engineering control?
A
Fume hoods, biosafety cabinets, automated sampling on equipment, substitution of less toxic substance, radiation shielding, etc
5
Q
What is the Administrative control?
A
Safe work procedures, training, etc
6
Q
What is the Personal Protective Equipment control?
A
Eye protection, gloves, gown, respirators, masks, etc
7
Q
What is Decontamination?
A
Procedure that removes contamination by killing microorganisms which makes items safe for use or disposal
8
Q
What are the 2 types of Decontamination?
A
Disinfection
Sterilization
9
Q
Disinfection:
A
A means of decontamination that refers to the destruction of specific types of organisms but not all spores, usually with chemicals
10
Q
Sterilization:
A
The complete destruction of all microorganisms by chemical OR physical means.
11
Q
What can sterilization be accomplished by:
A
- Steam autoclaves
- Gas sterilizers
- Filtration
- Dry heat
- Boiling
12
Q
What are chemical disinfectants used for:
A
Chemical disinfectants are used for decontamination…
- Of surfaces and equipment which cannot be autoclaved
- After spills of biohazardous material
- In discard jars and pipette jars
13
Q
What is Sterilization used for:
A
Complete destruction of all microorganisms
Used in some laboratories for equipment or materials used in tissue culture procedures or media preparation
14
Q
What are Autoclaves?
A
A strong heated container used for chemical reactions and other processes using high pressures and temperatures
15
Q
What are the proper controls of autoclaves?
A
Pressure
Temperature
Moisture content
Time
Contact
16
Q
What are the effective operating parameters for gravity displacement steam autoclaves:
A
- Temperature 121 celsius
- Pressure 15 psi
- Time 15 min or more
17
Q
What is an Indicator:
A
Used to determine if you’ve achieved successful decontamination and can be biological or chemical
18
Q
What must you avoid in autoclaves:
A
- Must avoid stacking items and crowding items to allow for adequate steam penetration
19
Q
What are Biological indicators?
A
- A test system containing viable microorganisms providing a defined resistance to a specified sterilization process (either in a strip or vial)
20
Q
How to tell if a biological indicator process failed:
A
If growth is detected, the sterilization process failed
21
Q
How to tell if a biological indicator was successful:
A
If no spores/bacteria grow, then the sterilization process was successful.
22
Q
How long is the incubation period:
A
8hr to 24hr
23
Q
What bacteria is used for sterilizers that use steam?
A
Geobacillus stearothermophilus
24
Q
Chemical Indicators:
A
- A system that responds to a change in one or more predefined process variables with a chemical or physical change
- Variety of chemical indicators, not all of which are steam, temperature, and time-dependent
eg. Paper strips impregnated with a chemical which turns from yellow to mauve when the proper conditions are met
25
What is Ergonomics:
1. Ergonomics is the science of designing work with the worker in mind
2. Integral part of work efficiency and a very important factor in the comfort and well-being of workers
26
What can Improper Ergonomics lead to:
- Musculoskeletal disorders (MSDs)
- Fatigue
- Repetitive motion injuries
- Monotony, leading to increased errors and accident rates
- Biochemical stresses creating strains, aches, injuries
- Eye strain from video display terminals
- Lowered morale
27
What is a Musculoskeletal disorder?
Disorders of muscles, tendons, and nerves
28
How do musculoskeletal disorders become hazardous:
Continual repetition
Forceful manner
Speed of the movements
Lack of recovery time
29
Examples of musculoskeletal disorders
Examples: carpal tunnel syndrome, tendonitis, thoracic outlet syndrome, tension neck syndrome
30
What are the 3 common risk factors (hazards) for MSDs
1. Force (Exertion, Effort)
2. Posture
3. Time
31
Force (Exertion, Effort)
1. Amount of compression occurring inside the body or applied to the body (ex. Resting wrists on a desk while typing on a keyboard)
32
Posture
1. Position of the body or a body part at any point in time
Ex: Bending forward, twisting your torso, reaching above shoulder level, reaching behind you, bending the wrists, reaching forward too far
33
What is Neutral posture?
When your body is positioned in a way that required minimal muscular effort
34
What is Deviated posture?
When your body is positioned outside of neutral, causing more stress on the body and putting you at greater risk for injury
35
Time
- Frequency of tasks or movements
- Duration of movements and postures
- Shorter, more frequent breaks are preferred over longer, infrequent breaks
36
Ergonomic Considerations and Solutions
1. Adjustability of lab benches
2. Variation of tasks
3. Design of lab space to avoid excessive or awkward bending, reaching, stretching, twisting, or other awkward motions
4. Lab stool and chair design
5. Anti-fatigue mats that are cleanable
6. Storing heavy materials on lower shelves
7. Using carts to move heavy materials
8. Design and positioning of display monitors for equipment
9. Indoor air quality factors such as temperature, humidity, and fresh air supply
10. Noise levels kept low
37
Physical Hazards:
1.Compressed gas
2.Cryogenics
3.Electrical Hazards
4.Ionizing Radiation
5.Non-Ionizing radiation
6.Temperature extremes
7.Noise
38
What are the dangers of compressed gasses:
1. Can explode if heated or damaged
2. Sudden release of high pressure gas streams may puncture the skin
3. Can present a toxic, flammable or corrosive atmosphere, depending on the properties of the gas
39
Precautions of compressed gas:
1. Secure gas cylinders firmly in an upright position
2. Secure the cylinder to an architectural support
3. Store gas cylinders in an area separate from the lab – Only gas cylinders connected to an apparatus should be present in the laboratory
4. Use four-wheeled hand trucks or dollies for transporting gas cylinders
40
What are Cryogenics?
Cryogenic fluids are liquefied gasses at very low temperatures (usually below -73.3ºC)
41
What are the physical Hazards of Cryogenics:
- Burns and other tissue damage (extremely low temperatures)
- Embrittlement of materials
- High pressure (build up in the container)
42
Common cryogenic material used in labs:
Liquid nitrogen, used for freezing and storage of biological materials
43
What to wear when dealing with cryogenics:
Wear personal protection when handling cryogenic material including impervious clothing, full face protection, and insulated gloves
44
What are electrical hazards?
Electricity is a potential ignition source and the cause of more
than 25% of fires
Can be fatal even at low voltage and low current
45
What does severity of Electrical hazard injury depend on:
1. Duration of contact
2. Voltage (and current)
3. Pathway of current through the body
4. Moisture content of the skin in contact with the electricity
5. Susceptibility of the exposed individual
46
Electrical precautions:
1. Avoid the use of extension cords and multiple adaptors
2. Use only electrical outlets equipped with a grounding connection requiring a three-pronged plug
3. Remove electrical cords from receptacles by grasping and pulling the plug, not the cord
4. If electrical equipment emits smoke or a burning smell, cut off the power immediately
5. Avoid placing electrical cords across areas of pedestrian traffic
6. Use only Class C extinguishers on electrical fires
47
What is Ionizing Radiation:
Radiation that has the ability to displace an electron from an atom or a molecule, thereby producing ions
48
Sources of Ionizing Radiation:
X-rays
Gamma rays
Alpha particles
Beta particles
Neutrons
49
How can you be exposed to radiation
1. Externally (radiation penetrates deeply into the human body)
2. Internally (nuclear substance is inhaled, ingested, or absorbed)
3. Exposure to ionizing radiation can produce both acute and chronic effects
50
What organs are at greatest risk of being affected by radiation exposure:
Blood-forming cells (bone marrow)
Breasts
Thyroid
Lungs
Digestive system
A fetus
51
What is non-Ionizing radiation:
Non-ionizing radiation refers to the types of radiation that do not carry enough energy to ionize atoms or molecules
52
Types of Non-Ionizing radiation:
Lasers
Microwaves
Ultraviolet radiation
53
What is the major danger of Lasers (Non-ionizing radiation):
1. Major danger of lasers to the worker is eye injury
2. Some lasers are intense enough to produce fire and cause instant injury to the eyes
54
What can Ultraviolet Lamps be used for:
Decontaminate equipment
55
Most injuries resulting from Ultraviolet Lamps are:
transitory (temporary)
56
What health issues can Heat Exposure cause:
1. Burns may result from direct contact with hot equipment, steam (from autoclaves), or liquids
2. May experience hyperthermia
57
What health issues can Cold Exposure cause:
May cause burns from contact with cryogenic agents or hypothermia from working in cold rooms and freezers
58
Noise:
- Unwanted sound
- Prolonged exposure to high levels of noise can produce physiological effects (noise-induced hearing loss, aural pain, tinnitus), psychological effects (disruption of sleep or relaxation), and it can interfere with communication (interfering with safety and job performance)
- Primarily affects concentration, communication, and overall quality of the workplace
59
How can Noise levels be minimized:
- Evaluate noise levels of equipment before purchasing
- Place noise-generating equipment as far away from workstations as possible
- Maintain equipment properly
- Consider engineering controls
60
Ways to reduce the hazards of pressure include:
1. Let pressure return to atmospheric before opening a vacuum desiccator or after removal of a sample container from a cryogenic liquid
2. Allow heated or cooled containers to return to room temperature before opening
3. Wear eye and face protection when handling apparatus under vacuum or under pressure and when manipulating frozen samples
4. Open containers slowly to allow pressure to equilibrate
61
Types of Psychological hazards
1. Stress
2. Abuse/violence
3. Bullying
4. Technostress
5. Fatigue related to shift work or long hours and overtime
6. Work-life conflict
7. Poor health
8. Age-related factors such as declining health, physical limitations, and intergenerational communication issues
9. Depression and other mental illness
62
Causes of Stress:
Work organizational factors:
Environmental factors:
Personal factors:
Laboratory work factors:
63
Work organizational factors:
Conflict
Working alone
Change and uncertainty
Technological change
Fatigue and hours of work
64
Environmental factors:
Noise
Indoor air quality
65
Personal factors:
Depression, anxiety, and other mental illness
Age-related factors
Work-life conflict
Substance abuse
66
Laboratory work factors:
Overtime
Urgency of the work to be done STAT
Ethical issues related to confidentiality of test results
Emotional stress of dealing with very ill patients
Making errors which may have serious impacts on the treatment of patients
Poor management-employee relations
67
Abuse/violence
1. Bullying
2. Verbal and sexual harassment
3. Physical and sexual assault
4. Intimidation and threats
68
What are the 5 Basics of preventing Abuse/violence
- A reporting system
- Early conflict resolution:
- Zero tolerance for disruptive behavior
- A well-designed workplace: Have an escape route behind you
- Clear emergency response procedures:
- Training and awareness:
69
Bullying Examples:
Bullying at work is the repeated, health or career endangering mistreatment of one employee, by one or more employees.
- Social isolation
- Rumours
- Over-monitoring of work
70
Technostress and ways to reduce the risk:
Stress caused by rapidly changing technology and the reliance on technology-based equipment
- Sufficient worker training to ensure workers feel confident and competent
- Having problem-solving resources available to support workers
- Back-up plans
- Worker participation in selection, trial, and implementation of technology
- Selection of technology that is designed to be easy for the user
71
Reproductive risks
Reproductive hazards are any agents that impact the ability to have healthy children
72
Reproductive risks of males:
Can affect males…
Reducing the number of sperm
Changing the shape of sperm
Altering sperm chromosomes
Impacting sexual performance
73
Reproductive risks of females:
Can affect females…
Menstrual cycle effects
Infertility or sub-fertility
Miscarriage and stillbirths
Birth defects
74
Reproductive Effects:
Problems in the reproductive process, which may be caused by a substance
75
Teratogen:
A substance which can cause birth defects
76
Embryotoxicity:
The ability of a substance to cause harm to the embryo
77
Fetotoxicity:
The ability of a substance to cause harm to the fetus
78
Mutagenicity:
The ability to cause changes in the DNA of cells (mutations)
79
Reproductive hazard precautions:
- Identification of the hazard and assessment of the risk
- Communication of information to employees
- Control of the hazard through engineering, administrative, as well as personal and procedural controls
80
Reducing reproductive hazard risks during pregnancy
1. Supervisor should be notified of a pregnancy so that a risk assessment of tasks and potential hazards can be done for that worker
2. Consult SDS, reference lists, infection control officers and institutional safety personnel are used to identify known reproductive hazards
3. Tasks may be reviewed and/or a measurement of the exposure level (depending)
4. Modified tasks
5. Temporary reassignment
81
Laboratory ventilation
1. Air is supplied through the building HVAC system
2. Control over air supply and air exhaust is important to provide control of environmental conditions within the lab
3. This can be referred to as “general ventilation”
4. Not the preferred means of controlling exposure to airborne substances: Local exhaust ventilation
82
Describe Chemical Fume Hoods:
1. Uses a duct system and fans to capture and remove contaminants within the hood
2. The more open the sash is, the lower the air velocity entering the fume hood becomes because the volume of air remains constant
3. Avoid disturbing the air flow by allowing only materials required to be inside the fume hood
4. Work with the sash as low as practical
5. Work with your hands as far into the hood as comfortable
6. Avoid cross drafts at the face of the hood
83
Biological Safety Cabinets
Variety of devices designed for user and/or product and/or environmental protection depending on the class of BSC
A system of air supply and removal that is designed to minimize the escape of aerosols
Rely on HEPA filters and include some recirculation of air in the cabinet
HEPA filters: high-efficiency particulate air filter
84
How to use a BSC:
1. Items should not crowd the rear of the cabinet
2. After placing all items needed to work in the cabinet, allow 3 – 5 minutes for air to purge and airflow to stabilize
3. Perform operations as far to the rear of the work area as is comfortable
4. Elbows and arms should not be resting on the grille or
work surface
5. Avoid excessive movement of hands and arms through
the front
6. Segregate non-contaminated items from contaminated –
Work should always flow from “clean” to “dirty” areas
7. Items should be discarded inside the BSC
85
Fume Hood vs BSC
A chemical fume hood is designed to remove chemical fumes and aerosols from the work area
BSCs are designed to provide both a clean workspace and protection for employees from aerosols created when working with infectious agents or toxins
86
Canopy Hoods
Designed to capture heat or contaminants from machines or processes
Ex: capture emissions from atomic absorption spectrophotometers or heat from autoclaves
Not designed for a personal workstation
- Air is drawn upward from the bench
- Less effective in capturing heavy vapors and aerosols
- More vulnerable to air turbulence because less enclosed
- Fail to provide adequate suction
87
Indoor air quality problems
May physically manifest as irritation to eyes, nose throat, neurological symptoms (ie fatigue, headaches, dizziness, nausea), or skin irritation and dryness
These problems can be related to a number of factors:
Temperature
Air flow
Humidity
Odours
88
Prevention and Control
Common solutions to air quality problems are mostly related to the HVAC system, which is not a system controlled by those working in the lab
We can put dehumidifiers in place to help control the humidity in areas, however this is not an ideal solution
Knowing when and who to contact with regards to air quality problems is key
89
What does HEPA filter stand for?
high efficiency particulate air filter
