Handling Toxic Situations
Effective chemical emergency management requires the right mix of technologies and training.
Imagine you've been thrust into the cockpit of a packed commercial airliner on its final approach, you've never piloted an airplane—and now, you're at the controls. "Scary" doesn't begin to describe how almost anybody would feel in a situation that pressure-packed and urgent.
And yet, for organizations that handle hazardous chemicals, the potential exists to be thrust into similar circumstances if a toxic chemical agent were to escape containment. Whether you are the manager responsible for plant safety, the CEO, or a first responder, you will want to be ready and able to handle such an event, because if it happens and it's significant, you won't be given a second chance.
Toxic chemical emergencies are unlike any other disaster. An earthquake occurs with little or no warning and often leaves great physical damage in its wake, but you can see and feel its effects and the worst of it is over in a few minutes.
A toxic chemical release, by comparison, is far more protracted, and potentially far more deadly. While it's true the release will continue only until the leak and any pooled material have been mitigated, the hazard often lasts much longer and can cover an expansive area, often at highly toxic levels as the plume continues downwind. In addition, because it is subject to changing weather conditions and even to differences in terrain, the chemical cloud's concentration and movement are difficult to predict. Worst of all, it is often invisible and can happen and continue without your knowledge.
Although a chemical emergency may unfold slowly, it demands intense concentration and a quick, definitive, and correct response.
It Can Happen Here
The mere existence of a chemical inventory, no matter the vessel design or configuration, gives rise to the possibility of a release. The fact is, toxic chemical releases do occur, with alarming frequency and when you least expect them.
The National Response Center is the nation's sole contact for reporting oil, chemical, radiological, biological, and other such discharges into the environment in the United States and its territories. Of the 30,601 incidents NRC recorded during calendar year 2007, employees and other people were injured or hospitalized in 1,142 incidents, at least one fatality occurred during each of 1,150 events, and property damage of up to $2.6 million was recorded in 286 cases.
The range of causes was equally remarkable. While preventive maintenance is at the heart of incident prevention programs, some managers may be surprised to learn that "equipment failure" was cited in 8,852 of the 30,601 incidents. Few expect a chemical container will be pressurized beyond safe limits, yet that caused 116 incidents. Explosions accounted for 150 incidents; natural phenomena, including earthquakes, floods, hurricanes, and tornados accounted for 1,064; operator error was cited in 778 cases; and suicide in 90. Unknown causes were cited in more than 3,100 incidents.
The point is, unplanned events happen. And when a hazardous chemical may be involved, it's vitally important to be aware of the danger and be prepared to handle it.
Proper Chemical Emergency Preparedness
Most business problems pale in comparison to the potential risk of not having a chemical disaster plan in place, not employing the best possible technologies to help save lives, not knowing how to use the tools, or not practicing their use.
Yet with the occasional exception of hand-held manual sampling technology, many sites are "blind" and limited with respect to the information they can gather and use to assist and guide their facility or community during a release. Few have real-time tools and resources in their emergency operations center (EOC), some incidents occur for hours before detection, and most take much longer to assess and resolve.
Chemical emergency preparedness requires reliable tools and tried and tested procedures. The basic tools include chemical sensors, appropriate alarms, access to local real-time weather information, and the ability to accurately predict plume movement and concentrations for best- and worst-case scenarios. Using that information, proper procedures are developed and refined.
Technologies and Techniques
To get started, you need to know the properties of each chemical involved as well as any mixtures. Is the substance heavier or lighter than air? How corrosive? What is the effect on people? What is the odor concentration? At what concentrations is it toxic? Will it react with the environment or other chemicals?
Next you need to know how each should be detected: To do this, match your chemicals' behavior to appropriate sensors (electromechanical/optical; wired/wireless); and know where and how sensors should be placed for maximum effectiveness (low or high off the ground? handheld or fixed? installed in the process unit or at the fenceline?).
Because your best shot at dealing with a release is to contain it, you need to know the source area—where it's coming from. Is it a gas well, storage tank, pipeline, or loading rack? Is it upwind or downwind from your facility? The release might even be from a neighboring facility, a tanker truck, or railcar— but you'd still immediately implement your emergency plan to protect your workforce and then alert the authorities.
Knowing the source area enables determining the most likely plume path. Knowing current meteorological conditions is equally vital: winds may be seasonal; and other factors including temperature, humidity, and solar radiation may vary greatly at different times of the year—or different times of day. The importance of this information, coupled with the mathematical complexity involved in calculating it, makes a convincing case for employing a system that can assess the data for you using real-time weather data and display the results graphically.
Next, you need to know what is in the likely path. Parts of your facility? Other facilities? Schools? Playgrounds? Highways? Hospitals or nursing homes? Neighborhoods or office buildings? And how will you monitor a plume that goes beyond your fenceline and the reach of your sensors?
Your system's ability to detect chemical presence and predict the plume path will provide valuable information, helping you to quickly assess the safety of designated muster points and evacuation routes, determine whether to shelter in place or evacuate, and communicate effectively with the appropriate officials.
Practice Makes Perfect
Given the unpredictable and potentially costly consequences of a toxic chemical release, you'll want to be sufficiently prepared to minimize the risk of having an event, and to mitigate the effects if one were to occur. To have the odds stacked in your favor, you need to know how you should respond—Now! Immediately!—in case an incident should occur.
The best way—realistically, the only way—to prepare for a chemical incident is to simulate different scenarios of what could happen during an event and practice using that information to develop the best procedures and responses for your situation.
Much like a flight simulator that trains pilots to fly before they're seated in a real cockpit, tools are available that can simulate the critical aspects of a chemical release and let you track it, map it precisely to the topography around your facility, and even predict its course and concentration using realtime or simulated weather data.
These tools simplify setting up a continuous improvement process, allowing you to review the event and the data generated, and to measure, evaluate, and correct or update your systems and procedures to reflect the lessons learned.
The High Cost of an Accidental Release
During uncertain economic times, many companies are idling production capacity, cutting spending, and reducing staff. Under these conditions, it seems hard to justify installing a sophisticated monitoring and response system. However, the risk of a chemical release doesn't diminish during difficult times.
If your company handles hazardous materials, it probably has expended significant time and money to understand, define, quantify, document, and communicate the risks to employees, stakeholders, and the community. Incident prevention, emergency preparedness and response programs, systems and procedures can require significant investment—but their cost pales in comparison to the disruptive, stressful, and painful aftermath of a disaster.
The Benefits of Planning and Preparedness
Having the right tools in place, knowing how to use them, and conducting drills with the most accurate information about your particular situation will help your company and its workers in a number of ways.
With the right mix of technologies and training, you'll be better able to assess risks, institute more effective procedures, and reduce the chances of occurrence. You'll also be equipped to engage in better decision-making and faster response—and maximize your chances for a safe landing if a real emergency were to occur.
This article originally appeared in the July 2009 issue of Occupational Health & Safety.