Emerging Threats in Public Health: Explosives
INTRODUCTION
Health threats to the public are constantly changing. With emerging and reemerging infectious diseases, biological and chemical attacks, and other environmental hazards, it is critical that all public health professionals are informed about the latest threats and emergency management processes. During a public health crisis, everyone plays an important role. From the clinical providers, emergency medical specialists, pharmacists and administrative staff who communicate directly with the public, to the epidemiologists, environmental specialists and laboratory technicians who work behind the scenes to resolve an emergency situation.
This training provides you with basic information about emerging health threats and the role public health plays in responding to these crises.
WELCOME
Public health faces many challenges. In the past three decades alone, several new diseases have emerged, from Legionnaire’s disease and toxic shock syndrome in the 1970s; to AIDS in the 1980s; and the West Nile virus infection in the 1990s. In this century, SARS and the terrorist threat of anthrax have challenged us. Whether a new disease is from a terrorist and intentional or from nature and accidental, we must be prepared. At Emory University’s Rollins School of Public Health we have the expertise and commitment to help prepare the public health workforce. Our Center for Public Health Preparedness and Research at Emory is pleased to present you this interactive training. Thank you.
MODULE 1: INTRODUCTION TO EXPLOSIVES
Introduction
This training module introduces the topic of explosives and includes the following chapters:
1.1 The Threat of Explosives
1.2 History of Explosives
1.3 Summary
By the end of this module, you will have a better understanding of explosives, how explosives have been developed and used throughout history, and how the use of explosives for terrorist purposes poses a threat to the public’s health and safety.
1.1 The Threat of Explosives
Explosives have been a part of human history for hundreds of years. However, recent history has illustrated how explosives can pose a threat to the public’s safety.
1983 - United States Marine Barracks and United States
Embassy Bombings,
1990s - 21st Century - Suicide Bombings,
1995 - Oklahoma City Bombing
1998 - Embassy Bombings in Nairobi and
2004 - Madrid
As illustrated by these examples, terrorist bombings oftentimes are targeted to injure the general public, suddenly and without warning in busy, populated environments. Thus, it is clear that the public health workforce must be prepared to handle such emergencies.
DEFINING
EXPLOSIVES
A chemical explosive is a substance containing a large amount of stored energy that can be released suddenly, thereby converting the substance into rapidly expanding compressed gases. There are two types of explosives: high and low.
High Explosives
A high explosive produces a reaction called detonation. Detonation occurs only with high explosives like TNT or dynamite. Explosive detonation occurs at a rate that is faster than the speed of sound (supersonic), and produces heat and gas. Most high explosives detonate at velocities between 1 and 9 kilometers per second. For example, the chemical explosive C4 detonates at 8 kilometers per second, or 5 miles per second.
Most importantly, detonation creates a blast wave, which causes the most immediately life-threatening blast injuries. The blast wave, also called a shock wave, arrives as a punch of energy traveling faster than the speed of sound, with high-pressure air erupting in all directions from the explosive. Within milliseconds, the blast wave will travel through the air and knock over all objects, including people that are in its path. Most terrorist bombings, especially those which have caused many deaths and injuries, use high explosives as the main ingredient in an explosive device.
Low Explosives
Low explosives like gun powder (sometimes called propellants or incendiaries), burn rather than detonate. The reaction of low explosives is also called combustion or deflagration. Although the burning process releases gas and heat, low explosives react below the speed of sound (subsonic). Most propellants burn between 0.1 to 1 millimeters per second, which is 10 million times slower than detonation velocities found with high explosives. Although low explosives react much slower than high explosives, the damage they cause can be just as significant. The September 11th attacks are examples of an explosion utilizing a low explosive, namely fuel from the aircrafts.
Bombings are the most frequent type of terrorist attack in the world. They have occurred more times than biological, chemical, radiological, or nuclear terrorist attacks.
The United States Department of State reports that between 1996 and 2002, bombings were the predominant type of terrorist attack internationally. After 1998, bombings represented at least 70 percent of all terror attacks on United States targets and citizens, greater than hijackings, kidnappings, armed attacks, arsons, and firebombings.
The criminal use of explosive materials is prevalent in the United States. The FBI Bomb Data Center reported that between 1988 and 1997, there were 17,579 bombing events that killed 427 people and injured 4,063.
PRODUCTION OF
EXPLOSIVES
About 5 billion pounds of explosives are produced each year; in 1995 alone, 950 million pounds were made. However, the majority of these explosives are used for legal (industrial and commercial) purposes. For example, explosives are used in the coal mining industry to blast for coal, which is then used to produce electricity. Explosives are also used for other forms of mining and spot welding.
The National Research Council reports that 90 percent of legal explosives are used in mining operations; 7 percent for road building, tunneling, blasting trenches, and other construction tasks; and 3 percent are purchased by thousands of individual users for purposes of smaller commercial jobs like removal of large rocks or tree stumps. The threat of explosives lies in their potential to cause public health injury and harm when in the hands of terrorists.
The focus of this training is the deliberate, criminal and terrorist use of explosives. It should be made known, however, that explosive materials have also caused fatal accidents in personal and workplace environments around the world. Regardless of whether an explosion is intentional or accidental, the public health concern remains an issue: lives are lost and people are injured.
EXPLOSIVES &
THE PUBLIC
Terrorist bombings have occurred around the world at office buildings, shopping malls, government facilities, courthouses, grocery stores, and on trains, airplanes, and buses. Because these attacks do not occur on a military battlefield, but instead in civilian environments, we must consider how they might impact affected populations.
Terrorist bombings yield patterns of injury that are frequently seen in military combat but less often in the civilian environment. Persons in the path of an explosion are likely to sustain multiple forms of trauma such as penetrating wounds, lacerations, burst ear drums, amputations, severe head trauma, and acute hemorrhage to the lungs and abdomen. Many times, these injuries are sustained simultaneously in several regions of the body such as arms, legs, head, and chest. Certain types of injuries are seen more often in specific types of bombings, as we will explore later.
Also, unlike military combatants, the civilian population
consists of more women, children, disabled, elderly, and special populations
who may require different types of medical care than the typical soldier. Anxiety, stress, and behavioral problems will
also likely surface following a terrorist bombing.
BOMB-INJURY THREAT
MODEL
In epidemiology, the science of public health, researchers and practitioners use the epidemiologic triangle to explain how illness or injury is caused. The model explains that the disease is caused by an imbalance among host, agent, and environmental factors. This model can also help to explain how explosions (the disease) impact public health. In this training, we will refer to the model as the bomb-injury threat model.
Host
In epidemiology, the host factors represent an individual’s characteristics that influence his or her vulnerability to a disease. When considered in the context of the public health impact of a bombing, the host factors consist of those traits that make a single individual or entire population susceptible to the injuries (physical and mental) that may result from an explosion. These can include general health status, age, sex, mental health background, and even socioeconomic status.
Agent
The traditional epidemiologic triangle explains that the agent is basically the hazard that produces a disease. The agent may be a simple pipe bomb, a large truck bomb, a suicide bomber, or an aircraft. The agent is the device which contains the explosive material that will detonate to cause injuries, death, and destruction.
Environment
Environmental factors are external characteristics that can affect exposure to an agent, effectiveness of an agent, or susceptibility of a host. In terms of bombings, environmental traits include the type of space in which the explosion occurs: a building, a small confined space, or a big open field. This will influence how the blast wave travels, and how it will interact with structures and people caught in its path of movement.
You should now have
a better understanding of the basics of explosives and their threat to the
public. Complete the following
interactive quiz to test your knowledge.
Select the correct answer or answers to the following
multiple choice questions. To start, select the Next button below.
MULTIPLE CHOICE
_____________ is/are the most frequent type of terrorist attack in the world.
Bioterrorism
Bombings
Chemical terrorism
Radiological and nuclear terrorism
Answer: Bombings
______________ result in a blast wave, the mechanism that can cause many serious blast injuries.
High explosives
Low explosives
None of the above
Answer: High explosives
According to the bomb-injury threat model, the _________ factors consist of those traits that make a single individual or entire population susceptible to the injuries (physical and mental) that may result from an explosion.
Agent
Environmental
Host
Answer: Host
According to the bomb-injury threat model, the __________ includes the type of space in which the explosion occurs: a building, a small narrow confined space, or a big open field.
Agent
Environment
Host
Answer: Environment
According to the bomb-injury threat model, the __________ is the type of explosive device used to cause the explosion.
Agent
Environment
Host
Answer: Agent
1.2 History of Explosives
In preparing the public health workforce for a possible explosive event, it is beneficial to know a general history of how explosives have been developed and used.
The following
timeline highlights some of the significant events in the History of
Explosives.
Each icon represents
a specific era or event. Select Next to
progress through the timeline.
THE EARLY YEARS
The Eastern World
10th Century
Black powder is believed to have originated in China during the 10th century. The basic mixture contained potassium nitrate, sulfur, and charcoal. The initial use of black powder was for fireworks and signals.
The Western World
1200 - 1500
An English monk, Roger Bacon, first introduced Europe to black powder. In the early twelve hundreds, he began experimenting with potassium nitrate. Realizing the powder’s explosive nature, Bacon kept his records in code.
Later in thirteen twenty, a German monk, Berthold Schwartz, studied Bacon’s writings and began his own experiments with black powder which led to its wider acceptance and use in Europe. By the end of the 14th century, black powder was being used to assist in military tactics including breaching city and castle walls.
THE 19th CENTURY
Discoveries of the
1800s
The 19th century was filled with many discoveries in the field of explosives.
Bickford’s Safety
Fuse
1831
In 1831, William Bickford introduced the safety fuse. This type of fuse enabled detonations to be more accurately timed, thus making explosions safer.
Sobrero’s Nitroglycerin
1846
In 1846 Ascanio Sobrero, an Italian chemist, discovered nitroglycerin. At this time more powerful explosives were needed for difficult mining and tunneling operations, but Sobrero abandoned his work with nitroglycerin due to its explosive and dangerous nature.
Nobel’s Blasting Caps
to Dynamite
1850s - 1890s
Alfred Nobel spent much of his career working with explosives, specifically nitroglycerin. Nobel joined his father in the development of a nitroglycerin manufacturing plant in 1863. After accidental explosions occurred in the manufacturing plants, Nobel expanded his work to focus on safety. This led to the development of a blasting cap which allowed for a safer initiation of nitroglycerin. While working towards developing a safer means of transporting nitroglycerin, Nobel invented dynamite.
EARLY 20th
CENTURY
In the beginning of the 20th century, while the danger of working with explosives continued to be made evident, the United States witnessed the first large-scale terrorist attack on its own soil.
Wall Street Bombing
1920
Shortly after noon on September 20th, a horse drawn cart carrying 100 pounds of dynamite and 500 pounds of fragmented steel exploded on Wall Street in New York City, which was filled with a lunchtime crowd. The explosion instantly killed 30 people, and by the end of the month 40 more people had died. Three hundred additional people were injured from the explosion. The attack in New York City was different from other explosions during this time because it did not appear to be aimed at any specific group.
1944
The Port of Chicago was a key location for loading ammunition onto naval ships during World War II. Unfortunately during these days, little training was provided to workers on the proper handling and loading of the ammunition.
On July 17th at 10:18 pm, two explosions occurred on a docked ship being loaded with ammunition. All 320 men on duty were killed instantly and 390 additional people were injured.
Texas City Disaster
1947
On April 16th, a docked cargo ship loaded with ammonium nitrate fertilizer caught fire in Texas City, Texas. Firefighters and dock workers labored to put out the blaze as onlookers gathered near the scene. Around 9:00 am, two explosions occurred almost simultaneously. These explosions resulted in the immediate deaths and injury of many people on the scene. In addition, the surrounding chemical plants quickly caught fire and collapsed. As the day progressed, concern grew for the potential explosion of another ship containing ammonium nitrate that had been burning all day. An evacuation of the scene was ordered at 1:00 am, and the ship exploded at 1:10 am with the most violent of all the explosions. The total number of deaths related to the events was estimated around 600, and 2,000 people were injured.
THE 1980s
Even as safety
measures improved through the century, significant accidental explosions still
occurred in the 1980s. In addition,
explosive attacks on the United States abroad became an increasing issue.
Beirut Bombings
1983
In the early morning of October 23rd, United States military forces in the 4-story building of the First Battalion, 8th Marines Headquarters were rocked by a massive terrorist explosion. A suicide bomber rammed his explosive-laden truck into the bottom floor atrium of the building located at the Beirut International Airport. The blast was estimated to have yielded a 6 ton TNT equivalent, equal to the explosion of 12,000 pounds of explosives. The blast immediately killed 234 United States marines.
Six months earlier, the United States Embassy in Beirut had been bombed in a similar attack. These attacks are considered the “watershed” of terrorism, forcing the United States to take notice of this growing threat.
Henderson Nevada Rocket Fuel Explosion
1985
On May 4th, Pacific Engineering and Production Company in Henderson, Nevada suffered an accidental fire and explosion which resulted in the complete destruction of the processing plant. A fire began in the plant around 11:30 am and was followed by three large explosions over the next 30 minutes. Two people were killed in the fire, while an estimated 300 were injured. The blast waves caused over 74 million dollars worth of damage across Henderson and Las Vegas.
LaBelle Bombing
1986
On Saturday, April 5th, a bomb exploded in West
Berlin’s LaBelle disco, killing two United States
servicemen and a Turkish woman. The
explosion came from a bomb packed with plastic explosives and shrapnel that had
been placed near the dance floor. Libyan
terrorists were blamed for the attacks, and 10 days
later the United States retaliated by bombing
THE 1990s
The 1990s continued to witness bombings occurring around the world, with an increase in the number of attacks on the United States both within its borders and abroad.
World Trade Center
Bombing
1993
On February 26th,
a bomb exploded in the basement garage of the World Trade Center Towers in New
York City. The explosion killed six
people and injured over 1,000 others.
Involvement by the Middle Eastern terrorist group Al Qaeda was suspected, and two years later 10
individuals were convicted of conspiracy in the crime. Their conviction was followed in 1998 by that
of Ramzi Yousef, believed
to be the mastermind behind the bombing.
1995
On the morning of April 19th, government workers at the Alfred P. Murrah Federal Building filed into their offices, and children were hurried into the resident daycare center. At 9:02 am, a massive truck bomb containing an estimated 2 tons of ammonium nitrate-fuel oil (ANFO) exploded. The detonation partially collapsed the 9-story structure. At this time, the bombing in Oklahoma City was the worst terrorist attack on United States soil: 167 people were killed including 19 children and 759 were injured.
Bombings of American
Embassies in Nairobi and
1998
At 10:30 am, August 7th, a large truck bomb exploded just outside the basement garage of the United States Embassy in Nairobi, Kenya. Although the 5-story embassy was left standing, adjacent buildings and banks were completely destroyed. At 10:39 am, a suicide bomber in another large truck drove up to the perimeter of the United States Embassy in Tanzania, but, unable to penetrate the gates, detonated the vehicle on the street outside. Between the two attacks at least 220 people were killed and nearly 4,000 injured, many of whom were bystanders.
Omagh Bombing
1998
In the decades prior
to the 1990s, bombings had occurred in Northern Ireland and England. However, on August 15th, the
single worst bombing incident occurred
in more than 30 years of violence in Northern Ireland. That morning, in a crowded shopping
center in a Northern Ireland town, Omagh, a car bomb
exploded killing 29 people and injuring hundreds of others. The
number dead and injured was possibly increased due to an earlier bomb threat,
which resulted in people being evacuated into the location of the actual
bomb. The “Real IRA,” a group of Irish
Republican Army dissidents, claimed responsibility for the bombing.
THE 21st
CENTURY
During the 21st century, terrorist bombings continued to become an ever present threat around the globe and within the United States.
Suicide Bombings
In the 21st century, “modern” suicide terrorism occurred around the globe most notably in Israel, Saudi Arabia, Russia, China, Indonesia, Philippines, Pakistan, and the United States. In 2001, there were over 300 suicide attacks carried out in 14 countries by 17 various terrorist groups.
In Israel, suicide attacks began in 1993 and lasted until 1996. A second phase of attacks began in 2000 and continues in the 21st century. During the Intifada, or “uprising,” Israel has experienced an onslaught of suicide bombings, killing and injuring Israelis in public places like markets, shopping malls, grocery stores, hotels, and commuter buses.
Russia Bombings
2000-2004
Hundreds of Russians and Chechens were killed in bombings on
civilian targets throughout Russia.
Female suicide bombers called “Black Widows” were sometimes the culprit
of these bombings. These women disguised
themselves in black robes, concealing explosive devices, killing between 10 and
sometimes up to 50 persons in a single attack.
Other times, car bombs and troops of suicide bombers were used together
to kill and injure. In an attack in
2004, between 400 and 600 people, many of whom were young children,
were killed in a horrific bombing and gunfire exchange in
9/11
2001
On September 11th, two hijacked jetliners hit the World Trade Center in New York City, causing Towers 1 and 2 to collapse. The impact and explosion of the two commercial airplanes was not the immediate cause of the collapse of the twin towers. Jet fuel that did not explode on impact seeped into lower stories, where it ignited and, along with other combustibles in the building, super-heated the structure. This weakened and eventually deteriorated the frames, resulting in the domino effect which progressively collapsed the floors and brought down each building. During and after the collapse of the towers, surrounding buildings were bombarded with debris clouds containing crushed building components, resulting in additional major structural damage and fires.
Another hijacked jetliner crashed into the Pentagon in Washington, D.C., and a fourth hijacked jetliner crashed into a field in Pennsylvania. Nearly 3,000 people died from the tragic incidents that are linked to the terrorist group Al Qaeda. These terrorist activities heightened public awareness of the threat of terrorism in the United States and intensified the government’s enforcement of security measures.
Preparedness Efforts
2002
In August 2002, the United States federal government
allocated over 1 billion dollars to state health departments and community
health systems via the Centers for Disease Control and Prevention (CDC) and the
Health Resources and Services Administration (HRSA).
The overall mission of the preparedness efforts was and continues to be the protection of public health and safety by improving the capacity of state and local public health systems to prepare for and respond to a bioterrorist act. In addition, the CDC provided funding to establish an integrated national system of Centers for Public Health Preparedness.
The focus of these centers is to improve the capacity of frontline public health and health care workers to respond to bioterrorism and other health emergencies by providing a continuum of accessible learning opportunities.
2002
On the evening of October 12th, three separate bombs exploded in a busy tourist area of Bali, Indonesia. The second explosion, the largest of the three, was a car bomb that resulted in over 200 deaths, mainly young people from two dozen nations, with the greatest casualties among citizens of Australia.
2003
On May 16th, suicide bombers simultaneously detonated bombs across Casablanca. Targets of the bombings included restaurants, hotels, a Jewish cultural center, and the Belgian Consulate. In total, 42 people were killed and approximately 100 others were wounded.
Riyadh Bombings
2003
On May 12th in Riyadh, Saudi Arabia, a multiple bombing attack utilizing several car and truck bombs, as well as human suicide bombers, occurred in four residential complexes housing many United States citizens. These bombings killed 25 people, in addition to the nine suspected bombers, and wounded nearly 200 others. The following November after another bombing during the holy month of Ramadan, the Saudi Arabian government took a hard stance against Al Qaeda and demonstrated an unprecedented willingness to cooperate with the United States in working against the terrorist group. Subsequent bombings occurred in or near Riyadh after 2003, including another bombing in a housing community, and a bombing on a Saudi government building in May 2004.
Madrid 3/11
2004
On March 11th, Spain was attacked by an onslaught of terrorist bombings on its commuter rail line. At 7:39 am, a quick succession of 10 explosions killed and injured rush-hour passengers along the 9-mile track running through residential and commercial areas. The devices, which were set off via cell phones, were estimated to contain over 20 pounds of high explosives each. Some bombs were placed together in backpacks, exploding with a blast so powerful that it ripped a gaped hole into the sturdy steel carriage of one train. Over 200 people died from the bombings and more than 1,400 were injured, making it the worst terrorist attack to date in Spain’s history.
You are now ready to
review the content within the History of Explosives timeline. Select Next when are you are ready to
continue.
TIMELINE REVIEW
To review the
content within the History of Explosives timeline select the desired era
icon. Select Exit Review when you are
ready to test your knowledge.
You should now have
a better understanding of the History of Explosives. Complete the following interactive quiz to
test your knowledge.
Drag and drop the
explosive symbol into the triangle for the correct description. To start, select the Next button below.
DRAG & DROP
Set 1
Introduced the safety fuse which enabled detonations to be more accurately timed thus making explosives safer (Bickford)
Discovered
nitroglycerin but abandoned his work with nitroglycerin due to its explosive
and dangerous nature (Sobrero)
Continued in his father’s work with nitroglycerin while also inventing blasting caps and dynamite (Nobel)
Set 2
Location of the
first large-scale terrorist bombing in the United States in 1920, which killed
over 70 people (Wall Street)
Location of multiple
bombings in 1983 on American targets outside the United States (Beirut)
Location of the 1995
bombing of the Alfred P. Murrah Federal
Building, which killed 167 people (Oklahoma
City)
Set 3
Location of bombings
in 2002 in a busy tourist area resulting in over 200 deaths of people from two
dozen different nations (Bali)
Location of 14
suicide bombings in 2003 on a variety of sites ranging from restaurants to
hotels, which killed over 42 people (Morocco)
Location of multiple
bombings in 2004 on the commuter rail line during morning commute, which killed
over 200 people (Madrid)
1.3 Summary
Although explosives are produced for non-harmful, helpful industrial purposes, they can also be used in injurious ways to commit criminal and terrorist acts. Bombings are the most frequent type of attack worldwide, and thus the public health workforce must be prepared to handle such an event.
To better understand how the public’s health is impacted by these bombings, we use an adaptation of the epidemiologic triangle: host, agent, and environment. Host factors are characteristics of the individual or the population that is affected by the blast. Agent factors are features of the bomb and explosive itself. Environment factors explain external components of the bombing like where it exploded.
The next training module provides a more in-depth explanation of each element from the epidemiologic triangle as it relates to bombings, as well as public health response to an explosive event.
Select Next when you are ready to begin the next module.
MODULE 2: EXPLOSIVES AND THE
PUBLIC HEALTH RESPONSE
Introduction
This training module includes the following chapters:
2.1 Agent: Characteristics of Explosives
2.2 Environment: Locations of Explosives
2.3 Host: Injuries Related to Explosives
2.4 The Public Health Response
2.5 Summary
Module 1 of this training introduced the epidemiologic triangle, which is based on three components: the agent, the environment, and the host. In this module, these three components will be used to describe how explosions impact public health.
2.1 Agent: Characteristics of Explosives
According to the epidemiologic triangle, the “agent” is defined as the hazard that induces the particular disease and/or injury. When considering explosives, the actual explosive device is the agent. This chapter will focus on chemical explosives, bombs, and their respective characteristics.
Chemical explosives are
one of five types of explosives which also include steam, atomic, nuclear, and
electrical. During a chemical explosion, the explosive matter, which can be a
solid, liquid, or gas, undergoes a rapid chemical reaction when triggered by a
detonator. This reaction results in
large amounts of rapidly expanding heat and gaseous pressure and is accompanied
by a loud bang. Based on the speed of
this reaction, explosives are classified as high or low explosives, as
discussed in Module 1.
High Explosives
High explosives, such as dynamite, nitroglycerin, and plastic explosives, result in two destructive forces which can cause major trauma and injury. The rapid explosive reactions unique to high explosives are referred to as detonation. The gases created by detonation expand at a rate faster than the speed of sound. This generates a shattering supersonic pressure wave referred to as a shock or blast wave, which moves out from the explosion site in all directions. Another destructive force comes from a blast wind. The blast wind is a forced super-heated air flow that originates at the explosion site following the blast.
Both the shock wave and the blast wind (distinct to high explosives) are powerful enough to injure individuals in the surrounding area of the explosion. The organs most vulnerable to the force of the shock wave are the gas-filled organs, specifically the lungs, ears, and gastrointestinal tract. Other parts of the body (such as the legs, arms, head, and abdomen) can be injured from shrapnel, falling debris, or trauma when the body is thrown by the blast wind.
Low Explosives
Low explosives do not generate a shock wave, and do not detonate at a supersonic rate. Examples of low explosives include gunpowder, firecrackers, and cherry bombs. Low explosives are a mixture of combustible substances that when ignited undergo rapid combustion, referred to as deflagration. These types of explosives release a large amount of energy, but at a relatively slower (subsonic) rate than high explosives.
A distinctive type of low explosives is an incendiary. These explosives, which include gasoline and “Molotov Cocktails,” ignite into a conflagration (an intense and uncontrollable burn). Despite the slower energy release, low explosives can result in as much destruction as high explosives. The term “low” does not imply that the effects of these explosives are small - these materials were used in the September 11th attacks to cause extensive damage.
High and low explosives are used for a variety of commercial and military purposes. The focus of this training, however, is on explosives used as terrorist weapons, most commonly in the form of bombs.
A bomb is a device designed to explode in a specific manner. Bombs may be placed, dropped, thrown, or projected. There are different methods used to set off a bomb (time, action or motion, command, or remote control), in addition to different procedures used to control the explosion of the device (burning, corrosive, electrical, or mechanical). Bombs are also made with different types of containers. The type of container used affects how well the bomb’s components are held together, whether the bomb can be concealed, and how and at what velocity fragments will be released upon detonation. Pipe bombs are commonly used by terrorists because the container is simple to construct and easy to conceal.
A specific term used to describe terrorist bombs is “Improvised Explosive Device” (IED). This type of bomb differs from manufactured military ordnance. Military ordnance (such as manufactured bombs, rockets, grenades, missiles, and munitions) produce predictable patterns of injury and use advanced technology and pinpointed delivery systems to maximize effectiveness. Military ordnance use only high explosives and target specific locations so as to minimize civilian and “friendly fire” casualties.
Terrorists will often use whatever is available (high and/or low explosives) but generally do not have access to advanced canisters, shrapnel, and delivery systems. Lacking sophisticated weaponry, terrorists often attack “soft” unfortified commercial targets, using excessive amounts of available high explosive, crude shrapnel, and relying on human couriers to get as close as possible to their targets (such as suicide bomber, car bomb, or commandeered aircraft).
Explosive materials and bombs are the most common cause of injury during terrorist attacks. By understanding how explosives can be an agent used to cause disease and injury, public health professionals are better suited to help those affected.
You should now have
a better understanding of explosives and their characteristics. Complete the following interactive quiz to
test your knowledge.
Drag and drop the
explosive symbol into the triangle for the correct description. To start, select the Next button below.
Set 1
Explodes by detonation at a speed faster than sound (High explosive)
Is a device designed to explode in a specific manner (Bomb)
Is a forced super-heated air flow that originates at the explosion site following the blast (Blast Wind)
Set 2
Burns by deflagration below the speed of sound (Low explosive)
Is a crudely crafted explosive, such as a “Molotov Cocktail” (Improvised Explosive
Device (IED))
Is created by a shattering supersonic pressure wave which moves out from the explosion site in all direction (Blast wave)
2.2
Environment: Locations of Explosives
The second component of the epidemiologic triangle is the “environment” - referring to the environment in which the explosion takes place. The environment has a direct effect on the severity and type of injury sustained, and it is a potential predictor for emergency resource utilization. This chapter will feature the three main environmental categories for explosions: open space, confined space, and structural collapse.
Open Space
Open space is a type of environment - such as a field or stadium - where few structures or obstacles are in the pathway of the blast movement. When the explosion occurs, the openness of the surrounding environment allows the blast wave to travel freely. The resulting pressure from the blast can therefore dissipate at a rapid rate. Open space explosions usually have fewer on-scene fatalities than the other environments under discussion. On the other hand, the open space environment presents more danger of injury from flying objects and shrapnel.
Confined Space
Confined spaces are the opposite of open space environments. They are narrow, tight, enclosed environments such as night clubs, bars, bathrooms, offices, hallways, commuter buses, or train carriages. When the blast occurs, its shock wave will reflect against walls, floors, ceilings, and other hard surface objects. Everywhere the blast hits a hard surface, it multiplies the original high pressure from the explosion, creating a pressure that is 3 to 9 times greater than the initial blast. This is because the pressure lacks a mechanism to vent to the surrounding environment, and therefore accumulates in pressure each time the shock wave reflects against a hard surface. Among the three environments, confined space explosions have the second highest incidence of on-scene fatalities. Because of confinement around the explosion and the resulting accumulation of blast pressures, there are more severe injuries to the lungs and gastrointestinal tract.
Structural Collapse
Structural collapse explosions cause the partial or complete framework destruction of a building. An explosion of this size could be caused by a large bomb containing several hundred kilograms of high explosive material. High explosives, however, are not the only type of material capable of being used in large amounts to cause building collapse. The attacks on September 11th involving tons of aircraft fuel, a low explosive material, caused the complete collapse of both towers.
Structural collapse explosions have the highest rate of on- scene fatalities, and rescue operations generally take longer due to safety concerns for rescue workers. Injury patterns are similar to those found in confined space bombings but also include bone fractures, crush injuries due to prolonged entrapment, and respiratory injuries caused by the inhalation of smoke, dust, and toxic gases. Electrical systems are often wiped out from this type of bombing, leading to blackouts. In addition, sprinkler systems, elevators, and doors may malfunction contributing to mass panic, possible stampede injuries, strains, sprains, and psychological stress.
Public health professionals should immediately take into account the environmental category when responding to an explosion disaster. This information can be of critical importance to emergency personnel because the environment will be generally known from the outset, while size and type of explosive will not.
You should now have
a better understanding of environmental factors which could impact an explosion
emergency. Complete the following
interactive quiz to test your knowledge.
Select the correct answer or answers to the following
multiple choice questions. To start, select the Next button below.
Open space explosions usually produce more injuries from ________________.
Bodily trauma from being thrown against a wall
Collapsed lung
Shrapnel
Structural collapse
Which environment has the highest incidence of fatalities during an explosion?
Confined space
Open space
Structural collapse
All of the above have the same incidence rate
Commuter bus or train carriage bombings are examples of which environment?
Confined space
Open space
Structural collapse
All of the above
Answer: Confined space
2.3
Host: Injuries Related to Explosives
The third component of the epidemiologic triangle is the host. The term “host” refers to an individual or an entire population that is susceptible to injuries (physical and mental) that result from an explosion.
Medical care for blast injuries has generally been practiced on the military population, which primarily includes physically fit, healthy men between the ages of 18 and 35. Furthermore, soldiers exposed to blasts have generally been protected by equipment such as body armor and helmets, and often have immediate access to medical care. An explosion set by terrorists in a civilian population, on the other hand, would likely present very different injuries than have traditionally been treated by medical personnel. The civilian population will likely include a wide range of ages, levels of physical fitness, and most likely include people with more health problems. Furthermore, civilians will not be wearing protective equipment and may not have access to immediate medical care. Therefore, public health and medical sectors must become familiar with different types of blast injuries and treatment procedures. This chapter will outline the four main categories of blast injuries: primary, secondary, tertiary, and quaternary.
Primary Blast Injury
Primary blast injury occurs from direct exposure to the blast. The nature and extent of the injury is affected by how long one is exposed to the blast (duration) and the intensity of the explosion (peak overpressure). A condition called “blast lung” is an immediate life-threatening blast injury in situations involving high explosives. It has a high fatality rate even when immediate and appropriate medical care is administered. “Blast ear” is another common injury following a blast wave involving high explosives, as are injuries to lungs and the gastrointestinal tract. Exposed individuals are also at risk of going into shock, which can involve the cardiovascular and central nervous systems.
Secondary Blast
Injury
Secondary blast injuries are caused by the impact of debris, such as shrapnel and nails, that are propelled from the explosive device. Other secondary debris created by the force of the explosion, like pieces of cement, mortar, glass, and wood, can also cause bodily injury.
Tertiary Blast Injury
Tertiary blast injury occurs when the force of the blast throws a person against rigid surfaces, such as the ground, a wall, or furniture. This impact may result in multiple injuries and bone fractures. People are often unaware of their surroundings following the aftermath of an explosion, and often come to consciousness only to find they are several meters away from where they stood before the blast.
Quaternary Blast Injury
Quaternary blast injury includes other forms of injuries that are directly or indirectly caused by the blast, and are common among survivors. Quaternary blast injury can involve burns from the initial explosion, or objects that have been ignited as a result of the explosion (such as gas or electrical equipment). The heat that is generated by an explosion can also cause burns, as can contact with hot, dust-laden air. Incendiary explosions are more likely to cause burns than detonations.
Another type of quaternary blast injury is “crush syndrome,” in which individuals are trapped under heavy debris for a long period of time following the explosion. These types of injuries occur more often in situations where the blast was powerful enough to cause complete or partial building collapse. Vehicle bombs, for instance, can contain sufficient amounts of high explosives to cause the collapse of a building and trap survivors.
Additional common blast injuries include:
By understanding the unique origin, nature, and symptoms of injuries related to explosives, the public health workforce can better prepare for such an emergency.
You are now ready to
review the types of blast injuries caused by explosives. In the following interaction, you can view
different animations depicting a person sustaining one of the four types of
blast injuries. Although the injuries
are presented separately, it is important to remember that a person can suffer
from more than one type of blast injury after an explosion.
Select Next when are
you are ready to continue.
You should now have
a better understanding of injuries related to explosives. Complete the following interactive quiz to
test your knowledge.
Select the correct answer or answers to the following
multiple choice questions. To start, select the Next button below.
______________ blast injuries are caused by the impact of debris, such as
shrapnel and nails that are propelled from the explosive device.
Primary
Secondary
Tertiary
Quaternary
_________________
occurs from direct exposure to the blast.
Primary blast injury
Secondary blast
injury
Tertiary blast
injury
Quaternary blast
injury
“Crush syndrome,” in which individuals are trapped under heavy debris for a long period of time, is associated with which type of injury?
Primary blast injury
Secondary blast
injury
Tertiary blast
injury
Quaternary blast
injury
_____________________ occurs when the force of the blast throws a person against rigid surfaces, such as the ground, a wall, or furniture.
Primary blast injury
Secondary blast
injury
Tertiary blast
injury
Quaternary blast
injury
2.4
The Public
Health Response
The following chapter highlights some of the challenges faced by public health professionals in responding to explosions resulting from terrorism. However, it is important to realize that unexpected mass casualty events can also occur related to the manufacture, transport, and commercial use of explosives. Therefore, regardless of how or why significant explosive trauma may occur, the public health workforce must be prepared.
Preparation
Unfortunately, explosive devices are the most popular weapons of terrorism and the most common contributing cause of mass casualties. The panic and chaos surrounding an explosion are unique, and public health professionals should be prepared to respond to such an event before an explosion occurs. For this reason, public health professionals should become familiar with their agency’s disaster plan, as well as the plans of other emergency response organizations within their jurisdiction, before an actual incident happens.
Effective explosion disaster planning should include: development of a command structure; plans for immediate rescue and treatment of victims; communication with and management of community and hospital assets; treatment of emotional/psychological health issues for victims and responders; and security considerations. Simulation drills should be used regularly to rehearse the disaster response plans, and evaluations should be conducted in order to improve and revise plans.
On-Site Care
Following an explosion disaster, immediate on-site care of victims is essential. Upon arrival to an explosion site, specific actions are required to assist victims and protect responders.
Regardless of the source of an explosion, the resulting
scene should be considered hazardous.
Before responders can enter the area, it must be declared safe by trained
personnel who assess threats of structural collapse, fire, toxic materials,
live electrical wires, and most importantly, the presence of additional
explosives. Once the site is declared
safe from further hazards, communications (between disaster scene and hospital),
victim treatment, and transport measures should be established according to the
local/regional explosion disaster plan.
Off-Site Triage
The purpose of a triage is to evenly distribute medical treatment among the injured, without overwhelming the medical resources at hand.
An off-site triage location should be operational promptly after an explosion. The optimal location would be away from the blast scene (to avoid destruction from another blast), yet near hospitals and facilities equipped to attend to critically injured victims. Nearby medical facilities should be on notice however, as 50 to 80 percent of blast victims bypass triage locations and self-transport to the closest hospital.
The management of a triage facility should also be carefully planned. Most often an “upside-down” triage occurs with explosion events, meaning the more severely injured arrive after the less injured. The initial arrival of the less injured may consume staff resources if not properly planned for in advance. Also, as stated earlier, blast victims with less severe injuries may bypass the triage entirely and go directly to the nearest hospital or clinic. All of this should be accounted for within the explosion disaster plan. Effective triage and adequate resources are critical to providing the best care for those involved in an explosion emergency.
Treatment
Explosions and their aftereffects are tragic and deadly; between 70 to 90 percent of all fatalities will occur at the site of the blast. Survivors should be immediately removed from the area by extraction personnel once the site has been declared safe.
Immediate treatment of surviving blast victims includes stabilization, control of bleeding, cleaning and covering wounds, and splinting of fractures. In addition, the victim should be examined for signs of contamination possibly associated with the blast (such as a dirty bomb), which could be radiological, chemical, or biological in nature.
Emergency professionals should also be aware of emotional and psychological injury. While these injuries are not considered life-threatening, there is potential for long-term disability if not treated. Immediate counseling and stress debriefing for victims and rescue workers should be available.
Collecting
Information
It is important to note and record all findings and observations of blast victims. If they are suffering from hearing loss (due to the blast) and are physically able, it may be better for them to write the details for you. This collected information serves multiple purposes: assist in the diagnosis and treatment of distinct injuries (covered in Chapter 2.3 of this training), determine future emergency resource needs, aid in reuniting families, and assist in the investigation of the incident. In the case of a criminal explosive act, this collected information will hopefully assist in the prosecution of those responsible.
Key Health Department
Contributions
In addition to the procedures presented earlier, the following are contributions public health agencies and departments can make in planning for and responding to an explosion emergency.
Locating casualties and connecting families.
Identifying available treatment capacity and preserving health resources.
Using past casualty and injury counts as predictors.
Providing ongoing community needs assessment
Locating casualties
and connecting families.
The surge of frantic families and friends seeking loved ones can be burdensome to hospital staff. A casualty locator, established at a location away from both the medical treatment facility and the scene of the explosion, can be a needed community service. In addition, this type of service can begin to create a victim trauma and exposure registry. Such activities should be coordinated with the local chapters of the American Red Cross.
Identifying available
treatment capacity and preserving health resources.
The vast majority of casualties only seek treatment at the
closest hospitals. Furthermore, patient
transfers to nearby facilities with extra room are sometimes hindered due to
chaos surrounding the incident. Health
departments, hospital associations, and regional coordinating hospitals can
assist in the identification of hospitals with excess capacity, encourage
transfer of untreated casualties to hospitals with waiting capacity, and
publicize area hospitals’ availability to provide non-disaster
care.
Using
past casualty and injury counts as predictors.
Data from past explosions can be useful predictors of casualties of a current event. Descriptive epidemiology, consisting of casualty and injury counts, provides data to decision-makers and the public. This requires close coordination with disaster scene responders, emergency medical services, and hospital emergency room management.
Providing ongoing
community needs assessment.
Vulnerable populations (such as the elderly, children, homeless, or those with chronic disease) can have special needs. Explosions could release toxic dust or chemicals, which may affect vulnerable populations differently. If information about community health needs and conditions are known, special measures can be taken for treatment. Furthermore, unfounded information can spread immediately within affected communities after an explosion. For example, rumors may spread the idea that the explosion was a mere diversion for an impending biological, chemical, or nuclear terror attack. Morale is improved and resulting panic reduced when agencies actively investigate potential misinformation and distribute factual information and instructions to the community.
Terrorism and heightened risk of explosions are a sober
reality of our times. Events such as
Oklahoma City and the World Trade Center bombings provided an eye-opening
perspective on disaster preparedness.
Continuous training, along with lessons learned from the past, must
ready the public health workforce to effectively plan and further improve our
response to explosion emergencies and their aftermath.
You should now have a better understanding of response measures for an explosion emergency. Complete the following interactive quiz to test your knowledge.
Select True or False for each statement. To start, select the Next button below.
TRUE & FASLE
Effective explosion disaster planning should be devoted to plans for immediate rescue and treatment of victims.
The scene of an explosion must be declared safe by trained personnel before responders can enter the area.
The optimal location for off-site triage would be away from the blast scene, yet near medical facilities with critical care resources.
Answer: True
Information collected from blast victims is only used for the prosecution of those responsible.
2.5
Summary
This training began with Module 1 providing an overview on explosives and the history of explosive materials and devices. This historical perspective provided insight on how explosives became a significant weapon of terrorism that it is today.
In Module 2, a more in-depth explanation was presented about types of explosives, their characteristics, and how they affect the body. This module concluded with a discussion about response measures required by the public health workforce to effectively respond to an explosion emergency.
Since their discovery in ancient times, explosives have been used in both productive and destructive ways. The public health workforce must be prepared to handle explosion emergencies, whether they are intentional or not. In a terrorist attack, additional challenges arise, first in administering on-site aid in a potentially dangerous environment, and second in identifying the specific type of injuries incurred by the public. Prompt treatment is essential after an explosion, thus it is critical for the public health workforce to be ready to respond quickly and efficiently to reduce the destructiveness of such an emergency.
Now that you have completed this training, you should have a basic understanding of the nature of explosives, how they could be used by terrorists, and how their threat to public health impacts preparedness planning and response.
HELP
This presentation explains basic instructions on how to perform the Emerging Threats in Public Health interactive training.
The training content is divided into stand-alone training modules which progress in a linear fashion. Each module should take you approximately 30 to 40 minutes to complete.
Designed in a user-friendly format with simple, intuitive navigation, the Main Menu Screen is your home-base that provides helpful information. Here you will access an introduction to the content, a welcome video, the training modules, the evaluation for the training, continuing education credit information, competencies objectives, and a printable transcript of the content.
At the beginning of each module, there is a table of contents. Clicking on a chapter takes you to the desired section.
To progress through the content of the chapters, select Next which moves you to the next screen.
Select the Back button to review content on the previous screen.
Selecting the Main Menu button will take you back to the main screen.
Throughout the training there will be interactive activities such as “True or False,” “Multiple Choice” questions, “Drag and Drop” exercises, and a timeline review. These interactive screens are indicated by a bar at the top and bottom of the screen. To leave these interactive pages and return to the content of the chapter, select Exit Assessment or Exit Review.
You should now have a better understanding of how to use this interactive training. You may watch this explanation over at any time. When you are ready to begin the training, select Module One from the Main Menu screen.