DRRR Quarterly Test Reviewer.pdf

DRRR QUARTERLY TEST KEY CONCEPTS TO REVIEW Hazards and Disasters A hazard is a potential source of harm or damage. It can be natural (like a volcano or earthquake), technological (like a nuclear accident), or hydr...

DRRR QUARTERLY TEST KEY CONCEPTS TO REVIEW Hazards and Disasters A hazard is a potential source of harm or damage. It can be natural (like a volcano or earthquake), technological (like a nuclear accident), or hydrometeorological (like a typhoon). A disaster occurs when a hazard actually causes significant damage or loss of life. Risk is the probability of a hazard causing harm, taking into account the hazard's severity and the vulnerability of the exposed elements. Mitigation involves taking steps to reduce or eliminate the long-term risk posed by hazards. This can include things like building protective structures, creating early warning systems, and educating the public. Preparedness involves planning and preparing for potential disasters. This includes creating emergency plans, assembling disaster supply kits, and participating in drills. Types of Hazards Natural hazards are naturally occurring physical phenomena caused either by rapid or slow onset events. They can be further classified into: o Geophysical: earthquakes, landslides, tsunamis, and volcanic activity o Hydrological: avalanches and floods o Climatological: extreme temperatures, drought, and wildfires o Meteorological: cyclones and storms/wave surges o Biological: disease epidemics and insect/animal plagues Hydrometeorological hazards deal with water in the atmosphere, especially as precipitation. Examples include typhoons, floods, and droughts. Geological hazards include internal earth processes like earthquakes, volcanic eruptions, and landslides. Biological hazards include outbreaks of diseases caused by microorganisms, such as epidemics and pandemics. Technological or man-made hazards are events caused by humans and occur in or close to human settlements. Examples include industrial accidents, pollution, and transport accidents. Impacts of Hazards Hazards can have various impacts on different exposed elements, including: People: injury, death, displacement, psychological trauma Property: damage or destruction of buildings, infrastructure, and crops Environment: pollution, habitat destruction, ecosystem disruption Economy: business interruption, loss of income, increased costs Volcanic Hazards Volcanic hazards are phenomena associated with volcanic activity that can pose a threat to life, property, and the environment. Primary hazards occur directly from the eruption and include: Lava flows - Streams of molten rock that can destroy everything in their path. Pyroclastic flows - Fast-moving currents of hot gas and rock fragments, extremely dangerous due to their high temperatures and speeds. Ashfall/tephra fall - Volcanic particles ejected into the atmosphere, causing respiratory problems, disrupting transportation, and damaging crops. Ballistic projectiles - Rock fragments ejected from the volcano's mouth, posing a threat due to their force of impact. Volcanic gases - Can be toxic and cause respiratory problems, acid rain, and other environmental damage. Secondary hazards are indirectly caused by the eruption and include: Lahars - Mudflows formed when volcanic debris mixes with water, often triggered by rainfall. Tsunamis - Giant waves generated by volcanic eruptions or landslides, posing a threat to coastal communities. Landslides/debris avalanches - Massive collapses of the volcano's slopes, causing widespread destruction. Signs of an Impending Volcanic Eruption Increased seismic activity - Volcanic quakes and tremors indicate magma movement beneath the surface. Changes in gas emissions - Increased or changes in the composition of volcanic gases can signal an impending eruption. Ground deformation - Swelling, tilting, or cracking of the ground can indicate magma intrusion. Changes in hydrothermal activity - Changes in the temperature or chemical composition of hot springs, wells, and crater lakes can be a sign of rising magma. Other signs - Drying up of vegetation, increased steaming activity, crater glow, and unusual animal behavior. Earthquake Hazards Earthquake hazards are phenomena associated with earthquakes that can cause damage and loss of life. Primary hazards occur directly from the earthquake and include: Ground shaking - The rapid vibration of the ground caused by seismic waves, leading to structural damage and collapse.  Ground rupture/displacement - Deformation of the ground surface along the fault line, causing fissures and offsets. Secondary hazards are indirectly caused by the earthquake and include: Liquefaction - Saturated soil loses strength and behaves like a liquid, causing buildings to sink or tilt. Landslides - Down-slope movement of rocks and debris triggered by ground shaking. Tsunamis - Giant waves generated by underwater earthquakes, posing a threat to coastal communities. Fires - Caused by ruptured gas lines, electrical damage, and overturned stoves. Tsunami Signs and Safety Natural signs of an impending tsunami include: Feeling a strong earthquake near the coast Seeing the ocean water recede unusually far from the shore Hearing an unusual roaring sound from the ocean Tsunami Safety Measures: If you observe any of these signs, evacuate immediately to higher ground. If you are in a boat at sea during a tsunami warning, do not return to port. Move your vessel to deep water. Risk Assessment and Mitigation Risk assessment is a systematic process to identify potential hazards, analyze their likelihood and potential impact, and evaluate existing controls. Mitigation involves taking actions to reduce or eliminate long-term risks associated with hazards. This can include things like building protective structures, creating early warning systems, and educating the public. Earthquake mitigation strategies include enforcing building codes, retrofitting existing structures, and educating the public. Volcanic hazard mitigation involves developing early warning systems, creating evacuation plans, and restricting development in high-risk zones. Steps in risk assessment: Identify the hazards - through observation, Material Safety Data Sheets (MSDSs), hazard and risk surveys, discussion groups, and safety audits. Assess the risk - evaluate the likelihood and potential severity of injury or harm. Make the changes - implement control measures to reduce or eliminate the risks. Check the changes made - ensure that the new safety measures are effective and do not create new hazards. Preparedness and Safety Measures Earthquake preparedness includes creating a family emergency plan, identifying safe spots in your home and workplace, participating in drills, and having a disaster supply kit. Volcanic eruption preparedness involves staying informed about volcanic activity, having an evacuation plan, and preparing an emergency kit with essentials like masks and goggles. Tsunami preparedness includes knowing the warning signs, having an evacuation plan, and moving to higher ground immediately if a warning is issued. During an earthquake, if indoors, drop, cover, and hold on. If outdoors, stay away from buildings, trees, and power lines. Do not use elevators. During a volcanic eruption, follow evacuation orders, stay indoors if advised, and protect yourself from ashfall. During a tsunami warning, evacuate immediately to higher ground and stay away from the coast. Remember, being prepared and knowing what to do during a hazard event can significantly reduce the risk of injury and damage.