PAF 261: Hazards and Risk Management Flashcards

Comprehensive practice flashcards covering severe weather, biological and human-made hazards, risk management, and emergency planning.

What criteria define a severe thunderstorm in the United States?

A thunderstorm is classified as severe if it produces wind speeds greater than $58\,\text{mph}$, hailstones greater than $1\,\text{inch}$ in diameter, or a tornado.

What are the three essential ingredients required for a thunderstorm to form?

1. Fuel (water vapor, generally from mP or mT air masses), 2. An unstable atmosphere, and 3. A lifting mechanism (convective, orographic, frontal, or convergent).

What characterizes the mature stage of a thunderstorm?

The mature stage is the most dangerous stage, characterized by the simultaneous presence of both updrafts and downdrafts, bringing heavy precipitation, hail, tornadoes, or damaging winds.

What defines a derecho weather event?

A derecho is a widespread, long-lived windstorm associated with a squall line (bow echo) producing straight-line downburst winds exceeding $58\,\text{mph}$ along a path at least $250\,\text{miles}$ in length.

What meteorological conditions are required to officially classify a winter storm as a blizzard?

Winds greater than $35\,\text{mph}$, blowing snow reducing visibility to less than $1/4\,\text{mile}$ ($500\,\text{ft}$), and a duration lasting for at least $3\,\text{hours}$.

What unique mortality pattern was observed during the 1918-1919 Influenza pandemic?

The 1918 pandemic exhibited a W-shaped mortality curve, causing unusually high death rates among healthy young adults aged 20 to 40, in contrast to typical seasonal influenza which mainly affects the very young and elderly.

Which organism was mistakenly identified as the cause of the 1918 influenza pandemic?

The bacterium Haemophilus influenzae was wrongly identified as the causative agent, leading to the development and distribution of ineffective vaccines and treatments.

How did the Love Canal disaster in Niagara Falls, NY, influence United States environmental policy?

The discovery of 21,800 tons of buried toxic chemical waste that leached into homes and a school led to federal emergency declarations and directly prompted the creation of the 1980 Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), commonly known as Superfund.

What toxic substance was released during the 1984 Bhopal disaster in India, and what was its impact?

Approximately 40 metric tons of methyl isocyanate gas leaked from a Union Carbide pesticide plant on December 3, 1984, killing between 2,000 and 8,000 people within the first few days and injuring over 100,000.

What regulatory reform resulted from the 1989 Exxon Valdez oil spill in Prince William Sound, Alaska?

It led to the passage of the 1990 Oil Pollution Act, which mandated double hulls for new oil tankers and barges and set responsible party liability limits for economic damages.

What occurred during the 1979 Three Mile Island accident, and how did it affect nuclear power in the U.S.?

A mechanical pump failure combined with human error caused a partial reactor meltdown near Harrisburg, PA (rated INES Level 5), stopping the construction of new nuclear power plants in the U.S. for decades due to heightened public fear and distrust.

What caused the severe shrinking and ecological collapse of the Aral Sea?

Beginning in the 1960s, the Soviet government diverted its two main feeder rivers (Amu Darya and Syr Darya) to irrigate cotton crops in the desert, causing the 4th largest lake in the world to dry up into a hypersaline wasteland.

What action initiated the Flint Water Crisis in April 2014?

To save money, an appointed Emergency Manager switched Flint's municipal water source from Detroit Water (Lake Huron) to the untreated Flint River, causing lead to leach from aging pipes into drinking water and triggering a Legionnaires' disease outbreak.

How does the CDC classify blistering agents (vesicants) versus nerve agents?

Blister agents (vesicants) cause severe blistering of the eyes, skin, and respiratory tract on contact, whereas nerve agents disrupt the nervous system by interfering with neural signal transmission.

In radiation measurement, what do Becquerels, Grays, and Sieverts measure?

Becquerels (or Curies) measure the activity/decay rate of a radioactive source; Grays (or Rads) measure the absorbed dose of radiation energy; and Sieverts (or Rems) measure the biological dose-equivalent exposure to humans.

What are the three primary types of nuclear radiation?

Alpha ($\alpha$) particles, Beta ($\beta$) particles, and Gamma ($\gamma$) rays.

What chemical reaction produces photochemical smog?

Photochemical smog forms when sunlight reacts with primary air pollutants—specifically nitrogen oxides ($\text{NO}_x$) and volatile organic compounds (VOCs)—producing ground-level ozone and fine airborne particulate matter.

What are the four general characteristics used to classify hazardous waste?

Ignitability (flammables), Corrosivity (acids/alkalis), Reactivity (explosive/unstable compounds), and Toxicity (threats to human health).

What do the four colored quadrants represent on the NFPA 704 hazard identification placard?

Blue represents Health Hazard, Red represents Flammability/Fire Hazard, Yellow represents Instability/Reactivity Hazard, and White represents Specific Hazards (such as Acid, Alkali, Corrosive, Oxidizer, Radiation, or Use No Water).

According to 49 CFR regulations, how are hazardous materials categorized into 9 transport placard classes?

Class 1: Explosives, Class 2: Gases, Class 3: Flammable Liquids, Class 4: Flammable Solids, Class 5: Oxidizers & Organic Peroxides, Class 6: Poisons/Toxic & Inhalation Hazards, Class 7: Radioactive Materials, Class 8: Corrosives, Class 9: Miscellaneous Hazardous Materials.

How do bacteria, fungi, and viruses differ in cellular structure and reproduction?

Bacteria are single-celled prokaryotes that reproduce by binary fission; Fungi are eukaryotic organisms that reproduce via budding, fragmentation, or spores; Viruses are non-cellular agents containing either DNA or RNA that require a living host cell to replicate.

What distinguishes Biosafety Level 3 (BSL-3) from Biosafety Level 4 (BSL-4) laboratories?

BSL-3 handles indigenous or exotic agents that cause serious human disease primarily via aerosol transmission, whereas BSL-4 handles dangerous and exotic agents posing high individual life-threatening risk (such as Ebola) with no available treatment or vaccine.

What are the six links in the Chain of Infection?

1. Infectious Agent (Germs), 2. Reservoir (where germs live), 3. Portal of Exit (how germs leave), 4. Mode of Transmission (how germs spread), 5. Portal of Entry (how germs enter), and 6. Susceptible Host (next vulnerable person).

How is risk defined in risk management contexts?

In engineering, risk is the probability of a hazard event occurring. The Department of Homeland Security (DHS) defines risk as the potential for an adverse outcome assessed as a function of Threat, Vulnerability, and Consequence ($\text{Risk} = \text{Threat} \times \text{Vulnerability} \times \text{Consequence}$).

What is the difference between epistemic uncertainty and aleatory uncertainty?

Epistemic uncertainty stems from a lack of knowledge or data and can be reduced with additional research, whereas aleatory uncertainty represents inherent randomness or variability in a system and is generally irreducible.

What is the key distinction between a hazard and a disaster?

A hazard is a potential source of harm or difficulty (natural or human-made), whereas a disaster occurs when a hazardous event impacts a vulnerable community and exceeds its local resources, requiring external assistance.

How does UNDRR define resilience in the context of disaster risk management?

Resilience is the ability of a system, community, or society exposed to hazards to resist, absorb, accommodate, adapt to, transform, and recover from the effects of a hazard in a timely and efficient manner.

What are the four phases of the Emergency Management Cycle?

1. Mitigation (steps to reduce/avoid damage), 2. Preparedness (pre-event planning and training), 3. Response (urgent actions during/after an event to save lives and property), and 4. Recovery (post-incident rebuilding and restoring community function).

How do Predictable Surprises (Grey Rhinos) differ from Black Swan events?

Predictable Surprises (Grey Rhinos) are high-probability, high-impact events that leaders fail to prevent despite having all necessary information due to institutional inertia or procrastination. Black Swan events are extremely rare, hard-to-predict, unexpected events beyond normal historical expectations.

What are the differences between Strategic, Tactical, and Operational plans?

Strategic plans establish long-term direction (e.g., Hazard Mitigation Plans); Tactical plans outline short-range specific unit activities (e.g., THIRA); and Operational plans provide detailed step-by-step procedures to achieve objectives (e.g., Continuity of Operations Plans).

What is the 'Normalization of Deviance', and what famous disaster exemplifies it?

It is the social process where unacceptable or unsafe practices gradually become accepted as normal behavior because repeated violations occur without immediate catastrophic results. A key example is the 1986 Space Shuttle Challenger disaster.