Although most suicides injure only the suicide victims themselves, others may cause injury to anyone within close proximity. With law enforcement officers typically being the first on the scene of such incidents, they should be aware of the hazards and be able to recognize the signs of potential residual threats.
The death of actor Robin Williams in August 2014 focused more attention on deaths caused by suicide. Law enforcement personnel frequently respond to investigate unattended deaths. The cause of death in these cases can span a wide range, from accidental overdoses to homicides. In 2013, more than 41,000 deaths were caused by suicide in the United States making it the tenth leading cause of death for Americans that year. During 2013, that translated statistically into one suicide death occurring every 12.8 minutes. Suicide deaths among middle-aged Americans have been trending upward. According to the Centers for Disease Control and Prevention, more people now die from suicide than from automobile incidents in the United States.
Multiple Ways to Die
Various means are used to commit suicide. The most commonly used method among males in the United States is firearms, whereas American females most frequently opt for the use of poison. Generally, responding to a suicide, such as those where people orally ingest poison, does not pose any extraordinary threat to law enforcement officers. However, those who opt instead to cause their death through some type of inhalation exposure may very well pose an ongoing threat to those who respond.
One method people have opted to use is to commit suicide through the inhalation of carbon monoxide generated by running internal combustion engines in confined spaces. This is frequently accomplished by idling a vehicle in a closed garage. In these cases, responding police personnel need to ventilate the involved area to ensure that they are not affected by this toxic gas. This method often is readily identified for what it is because of the telltale indicators. Therefore, the potential danger is mitigated despite the fact the carbon monoxide is odorless and colorless.
Some more exotic, less frequent, and newly emerging methods to commit suicide via respiratory exposure may be less easily recognized. As a result, these methods may pose a significant threat of harm to responding personnel. Awareness of the threat posed by these methods may be lacking but, once officers are forewarned, they often can be alert for and recognize telltale indicators, which empower them to take actions to avoid injury. All members of law enforcement should be familiar with these trends to ensure their safety should they respond to one of these events.
Oxygen Displacement Hazards
Among the less common methods are asphyxiation through oxygen displacement, the inhalation of hazardous gases and chemical suicides (also known as detergent suicide). Asphyxiation through oxygen displacement often involves someone placing a bag over his or her head and then pumping in an inert gas, such as helium or nitrogen. Since helium is lighter than air, it fills the bag from the top down forcing all of the air out of the bottom of the bag. Accordingly, the bags used during these acts are sometimes referred to as suicide or exit bags.
Helium may be purchased in a variety of tanks – including disposable ones – from a number of locations, such as party supply stores. This method of asphyxiation reduces the unpleasant sense of suffocation commonly associated with oxygen deprivation in the presence of carbon dioxide, and it is even advocated on various suicide websites. Other gases that have been documented for bag suicides include propane, butane, or methane. Often, tanks of the gas are connected to a hose leading up into the bag, which may have a drawstring, be taped, or otherwise be secured around the neck to prevent the bag from becoming displaced.
Responders who encounter this method of suicide should be aware that, if it is completed in a confined space with poor ventilation, the gas may continue to displace oxygen in that area, creating an oxygen-deficient environment. Additionally, if a flammable gas such as propane is used, releasing the gas may create an additional risk of explosion or fire.
If a toxic gas, such as Freon or a concentrated pesticide like methyl bromide, is pumped into the bag instead of an inert gas, the victim may die directly from exposure to the concentrated poisonous gas. Once the gas release has been initiated, the toxic gas may continue to flow freely, thereby creating a risk of exposure to those who enter the immediate area. Whenever an apparent suicide involves a tank containing an unknown gas, extreme caution should be exercised and a hazardous materials response team should be requested to assess the situation. Telltale signs include the use of tanked compressed gases, hoses, or bags covering the head.
If the method can effectively kill the victim, it may pose an ongoing hazard to those who respond. Clearly, one of the greatest threats faced by personnel responding to suicides is one of an inhalation hazard – whether carbon monoxide, an oxygen deficient atmosphere, or an intentionally released toxic gas.
Chemical or Detergent Suicide Hazards
A newly emerging threat that has its roots in Japan is being used with increasing frequency in the United States. This trend has been dubbed “chemical or detergent suicide.” This method of death involves the intentional mixing of common household chemicals to generate an off-gassing of extremely toxic gases, generally either hydrogen sulfide or, less frequently, hydrogen cyanide. Off-gassing, also called outgassing, is the release of chemicals from various substances under normal temperature and pressure. Chemical suicide deaths usually occur in confined spaces, such as motor vehicles or closets, and generally do not involve the use of bags to further concentrate the gas.
Chemical suicide is most commonly performed when a person mixes readily available household chemicals containing sulfur together with a product containing hydrochloric or muriatic acid in the proper manner to create an off-gassing of deadly hydrogen sulfide, also called “swamp gas.” Products that contain sulfur include various fungicides and dandruff shampoos. Many toilet bowl cleaners and tile or stone cleaning products contain hydrochloric acid. Lists of potential ingredients as well as mixing instructions are readily available on the Internet.
In Japan, where this method began, over 2,000 incidents have occurred. Although this method of suicide is still relatively uncommon in the United States, it is trending upward in frequency. In order to attain the concentration of gas necessary to cause death, those using this method of suicide often do so in a confined space, common spaces used include inside a vehicle, small room, bathroom, or closet.
Generally, the two chemicals are mixed together in an improvised container, such as a pail or bucket. Some victims have mixed the chemicals in glove compartments or vehicle consoles. At high concentrations, one breath of hydrogen sulfide may be sufficient to cause death.
Hydrogen sulfide is a naturally occurring chemical formed by the decomposition of organic matter. It is colorless and has an odor similar to rotten eggs. Continued exposure may rapidly fatigue the sense of smell. The gas is heavier than air and, if it is released in a multistory building, it may sink to lower levels of the structure. Although hydrogen sulfide is flammable at certain concentrations and may create a fire or explosion hazard, flammability occurs at much higher concentrations than is necessary to cause death. Those committing suicide using this method often post signs to warn anyone who may find them of the danger involved from the gas.
In addition, victims frequently use tape to seal doorways and vents to keep the gas from escaping. If the gas is dispersed within a vehicle, it often results in the windows fogging up with a yellowish green tint or cause yellowish green residue deposits on the interior of the car. If there is loose change in the car, the gas causes pennies to become heavily tarnished to a blue-green color. Victims occasionally remove the interior door handles to prevent themselves from a last-second change of mind and prevent exiting the car. Since the mixture tends to cause chemical burns to skin and eyes, some victims wear gloves and goggles to spare themselves pain. Frequently, the ingredients containers are visible, as well as the improvised container used to mix them.
Additional Concerns for Hydrogen Cyanide
Some opt to commit chemical suicide by mixing products containing cyanide with strong acids to create hydrogen cyanide, which historically has been used to cause death in gas chambers and deployed as a chemical warfare agent. When compared to the use of hydrogen sulfide, this method is far less common due to the increased difficulty in obtaining the precursors. Unlike hydrogen sulfide, hydrogen cyanide is lighter than air, so it rises. It also is readily absorbed through the skin, so skin contact with liquid or vapors must be avoided. Like hydrogen sulfide, hydrogen cyanide has a distinctive odor, which in this case is similar to bitter almonds, and is flammable under certain concentrations.
Many law enforcement agencies have equipped their members with air purifying respirators. Although these units are effective for many hazards, they generally are insufficient for use at chemical suicide scenes. Self-contained breathing apparatus is recommended for these inhalation hazards and, in the case of hydrogen cyanide, fully encapsulating suits are recommended to prevent skin exposure. The safest course of action when these indicators are observed is to request support from a hazardous materials team or the fire service – assets that may not be routinely dispatched to potential suicides. When chemical suicides occur in vehicles, they also are initially dispatched as suspicious vehicle calls, which often result solely in a law enforcement response.
Attempts to resuscitate victims can expose responders to injury, as the victims are often contaminated with the product. Even the victims’ bodies should be considered hazardous, as they may release harmful gases after being removed from the site. Therefore, body bags are not recommended because they trap and concentrate toxic gases, thus creating a secondary hazard when they ultimately are opened. Law enforcement personnel have been injured responding to chemical suicides, so extreme caution should be exercised.
Respiratory suicides pose a unique hazard for law enforcement personnel and other responders. Whether compressed gases are released or household chemicals are mixed, awareness is the key to safe response. There usually are several telltale indicators present when these methods are used, but possessing the knowledge to recognize them is crucial for maintaining officer safety.
Stuart K. Cameron
Stuart K. Cameron is a 30-year veteran of the Suffolk County (New York) Police Department and currently serves as the chief of support services. He spent more than a decade overseeing the operations of the department’s Special Operations Commands. He also supervised numerous tactical assignments, barricaded subjects, bomb squad call outs, large crime scene searches, and hazardous material incidents. He has been involved in the development of national level procedures and homeland security training and has been an active instructor on topics related to homeland security and public safety. He is a subject matter expert on the role of law enforcement in the defense against radiological and nuclear terrorism and chaired a committee that developed the concept of operations for the Securing the Cities Program.