Understanding Pressure Level Classifications for Industrial Explosions

Houston is a large metropolitan area with its share of oil refineries and chemical plants. Wherever there are industrial plants with people working inside buildings, there is the potential for human lives to be changed or ended by a Houston chemical plant explosion. When injuries occur, the effects are not just on the victims themselves, but also on their relatives and friends. Large industrial accidents can devastate an entire community. Getting the Facts People working in industrial plants should be aware of the risks inherent in their workplaces. They are working around chemicals, which can explode unexpectedly and have immediate effects. Their employers are also responsible for considering levels of threats and taking preventive measures to minimize the human injuries and deaths. A major threat that immediately comes after a chemical explosion is the overpressure blast. Overpressure Threat Wherever chemicals are being used, an explosion can occur. After an explosion, there is an immediate blast wave. This powerful wave results from the energy that is released and travels at the speed of sound. The greater the chemical explosion, the greater the resultant blast wave is. A powerful blast wave can cause property damage and human casualties in the immediate vicinity of the explosion. Houston companies with operations that could produce chemical explosions must consider the potential of a blast wave in terms of the overpressure Level of Concern (LOC). If the pressure of the blast wave exceeds this threshold, a hazard can occur. Computer Modeling People who work in chemical plants and other industrial facilities may be surprised to learn that, according to the U.S. Department of Commerce Office of Response and Restoration, no well-defined guidelines or standards exist to assess an overpressure hazard. One way that Houston chemical companies can consider the potential hazards of a blast that reaches the overpressure LOC is through computer modeling. A good model enables users to input specific data points and predict the effects. For example, the Office of Response and Restoration’s ALOHA software, or air hazard modeling program, helps companies to run a vapor cloud explosion scenario and determine the threshold above which a hazard could occur. This government website also offers estimations of the level of injuries that could impact people near a blast wave. The risk is higher for people who are closest to the blast. The general guidelines are discussed below. Potential Injuries from Sound Blasts When a sound blast occurs immediately after a chemical explosion, the pressure wave might seem to be less hazardous than a toxic cloud or a fire. As the sound wave moves outward, there is immediate damage to property, creating pieces of building debris and broken glass, which can damage or flatten buildings and cause injuries and deaths to people inside them. If a blast has a power of 8.0 pounds per square inch (psi), destruction of buildings can occur. If a blast has a power of 3.5 psi, serious injuries to people are likely. It only takes a blast of 1.0 psi to shatter glass. Extent of Injuries Per Blast Intensity People working inside buildings are at risk for losing their hearing and sustaining serious or fatal injuries from a Houston chemical plant explosion. In the range of 1.0 to 8.0 psi, people can receive lacerations from flying glass and other missiles. In the range of 2.4 to 12.2 psi, people can experience 1 to 90 percent eardrum rupture. In the range of 14.5 to 29.0 psi, fatalities can occur among people directly exposed to a blast. Injuries and fatalities from sound blasts following chemical explosions may indicate the need for hiring a Houston refinery explosion attorney to obtain compensation under Texas law and to protect the legal rights of injured individuals.