Lecture 14 (Biohazards)

Question 1

Biohazard

Answer 1

Biological substances that threaten the health of living organisms
Sources include bacteria, viruses, and other animals

Question 2

Legistlation

Answer 2

Federal Human Pathogens and Toxins Act
Health of Animals Act and Regulations
Transportation of Dangerous Goods Act

Question 3

Standards and Guidelines (CFIA)

Answer 3

Containment Standards for Facilities Handling Aquatic Animal Pathogens (CFIA)

Question 4

Examples of Biohazards

Answer 4

Severe Acute Respiratory Syndrome
Hepatitis C 
HIV/AIDS
Swine Flu
Avian Flu
Salmonella

Question 5

Classification: Category A

Answer 5

Infections affecting animals and humans

Question 6

Standards and Guidelines (BMBL)

Answer 6

Biosafety in Microbiological and Biomedical Laboratories

Question 7

Classification: Category B

Answer 7

Infections affecting animals only

Question 8

Classification: Category C

Answer 8

Substances transported for diagnostics and investigative purposes

Question 9

Agents and Sources

Answer 9

Bacteria
Viruses 
Fungi
Parasites 
Blood borne Pathogens

Question 10

Bacteria

Answer 10

Simple one-celled organisms
Can be pathogenic, harmless or useful
Broken skin is vulnerable

Question 11

Viruses

Answer 11

Living non-cellular entities
Cannot survive without living cells
Common occupational exposures to animal virus, poxvirus and arbovirus

Question 12

Reckettsia

Answer 12

Similar to bacteria but smaller
Transmitted to humans via bloodsucking
Responsible for typhus and Rocky Mountain fever

Question 13

Parasites

Answer 13

Parasitic to plants or animals
Diseases include malaria, and other blood infections
Dermatitis and other skin problems are due to mites and chiggers

Question 14

Fungi

Answer 14

Either parasitic or saprophytic
Hypersensitivity due to fungal antigens
Fungal disease include athlete’s foot and ringworm

Question 15

Toxins

Answer 15

Poisonous substance produced by a biological organism

eg. cholera toxin, botulinum toxin

Question 16

Risk Assessment

Answer 16

A measure of the exposure probability, resulting in an adverse health effect
Risk = function (Severity x Probability)

Question 17

Risk Assessment Considerations

Answer 17

1. Pathogenicity/Virulence ability of organism to cause disease/degree
2. Availability of effective prophylactic and therapeutic treatments
3. Measure the mode of transmission and route of infection
4. Host Range number of species it can infect
5. Natural Distribution Region where pathogen is naturally found
6. Impact of Release

Question 18

RG 1

Answer 18

Low individual and community risk

Not capable or unlikely to cause disease in humans or animals

Question 19

RG 2

Answer 19

Moderate individual and low community risk
Can cause serious disease but chances are low
Effective and permanent treatment available

Question 20

RG 3

Answer 20

High individual and low community risk
Likely to cause serious disease
Effective and permanent treatment available

Question 21

RG 4

Answer 21

High individual and community risk
Likely to cause serious diseases and death
Spread risk high and treatment may not be available

Question 22

Containment Levels

Answer 22

Aerosol Generation
Quantity 
Concentration
Type of Proposed Work
Shedding

Question 23

Containment Level 1

Answer 23

Do not cause disease in healthy humans.

eg. E coli

Question 24

Containment Level 2

Answer 24

Potential hazard to personnel and environment:

eg. Salmonella

Question 25

Containment Level 3

Answer 25

Can cause serious/lethal disease via inhalation:

eg. SARS Virus

Question 26

Containment Level 4

Answer 26

Can be easily aerosol transmitted and cause fatal diseases in humans with no possible treatments
eg. Ebola virus

Question 27

Hierarchy of Controls

Answer 27

Engineering Controls
Administrative Controls
PPE

Question 28

Engineering Controls

Answer 28

Air Handling

• Inward directional air flow to prevent the escape of biohazards
• Filtration

Question 29

HEPA Filtration

Answer 29

High Efficiency Particulate Air Filtration
Captures 99.97% of particles through: 
Impaction
Diffusion
Interception

Question 30

Class 1 Biosafety Cabinets

Answer 30

Provide personnel and environmental protection

No product protection

Question 31

Class 2 Biosafety Cabinets`

Answer 31

Provide personnel, environmental and product protection

Further divided into sections A1,A2,B1,B2

Question 32

Class 3 Biosafety Cabinets

Answer 32

Product protection, and Maximum environmental and personnel protection
Designed for RG4 work
Complete enclosure

Question 33

Administrative controls

Answer 33

Work with animals, children, people known to be infectious
Large quantities, high concentrations
Transport

Question 34

PPE

Answer 34

Gloves
Eye protection
Lab Coats 
Face Mask
Suit with respirators

Question 35

Decontamination

Answer 35

Process by which materials rendered safe to handle and are reasonably free of micro-organisms/toxins

Question 36

Steam Sterilization

Answer 36

Effectiveness dependent on:
Temperature
Length of Time
Ability of the steam to penetrate the load

Question 37

Chemical Disinfection

Answer 37

Usually for equipment and work surfaces 
Effectiveness dependent on micro-organism and disinfectant as well as: 
Organic load
Concentration
Contact time (and more)

Question 38

Gaseous Decontamination

Answer 38

Used in higher containment zones

eg. Formaldehyde, chlorine dioxide, etc.

Question 39

Irradation

Answer 39

Gamma radiation
- good for heat sensitive materials
Ultraviolet
- only effective for airborne or surface contamination

Question 40

Incineration

Answer 40

Effectiveness dependent on:
Equipment design
Time
Temperature

Question 41

Effluent Treatment

Answer 41

Treatment of liquid wastes prior to release to sanitary sewer
Typically heat bases
Required for high containment zones (CL 3+)