"If you don't know, don't go, for it might blow" is a phrase that was often repeated in the early days of hazardous materials response training. This was the battle cry back in the 1970's when most of the available hazmat training came from the railroad industry. At that time it probably was not a bad concept; stay away from the hazards if the hazards were not known or the risks could not be properly assessed. Unfortunately, many responders have continued to grasp this concept and many are still being trained to the worst-case scenario type of response. This is known as the "Chicken Little Syndrome" where every hazmat incident demands a full response and commitment of personnel and resources. There is a better way!
The new millennium has dawned and hazmat response is still a reality. In fact, hazmat response is very technical in nature but it has proven to be very manageable. Experience and advances in training and technology have provided insights on how to handle hazmat incidents appropriately. That is, handling hazmat releases by gearing the response according to the hazards and risks present. This type of response has proven to be cost effective, time efficient, and safe for responders. Conversely, underplaying an incident should also be avoided for the same reasons.
The key to handling hazmat responses geared to the situation is through effective training that includes proper risk assessment techniques, determining the situational demands, making effective decisions, and examining case studies.
Frank Docimo, a national hazmat presenter, has developed a unique system where the risks can be quickly analyzed and assessed by simple means and consequently the appropriate level of response can be selected. Frank has impressed upon many students that the vapor pressure of the material released or spilled drives the response by emergency responders. If a material has a high vapor pressure there will most likely be high quantities of the material in a vapor state. This situation presents a possible inhalation hazard for unprotected people so evacuations may have to be considered and responders may have to don protective breathing protection. High vapor areas also present toxicity and flammability hazards depending on the hazards of the material released. High vapor pressures would be considered over 100 millimeters of mercury (mm/Hg). The higher the vapor pressure for a material the more vapors can be expected in the atmosphere.
With the above in mind, Frank would classify a liquid spill as a "good day in the neighborhood" based on vapor pressure. Most liquids have lower vapor pressures than compressed liquefied gases or compressed gases and therefore would not present as high of hazards in the areas of exposures or flammability. Also, solids usually have low to no vapor pressures and would not usually present toxicity or flammability hazards especially if handled safely and with adequate personal protective equipment.
As simple as it is, this system of analyzing the spilled or released material's vapor pressure presents an effective risk assessment tool. Coupled with researching the other hazards of the material such as biological indices, flashpoint, flammable range, and incompatibilities responders can quickly develop their tactical plans and safely handle hazmat releases.
Answers to these questions can also assist in decision making at hazmat emergencies;
1. What state is the material that is released?
- Solid- will have low or no vapor pressure.
- Liquid- will no, low, moderate, or high vapor pressure
- Gas- will have high or extremely high vapor pressure
2. What is the identity of the material that is released?
- As soon as safely possible attempt to find out the identity of the material through shipping papers, placards, labels, transporters, facility personnel, or detection devices.
- Research on the hazards of the material will also assist in determining its vapor pressure and other noteworthy hazards.
3. Weather conditions?
- The weather or conditions at both inside and outside releases will also help determine what the material released will do or how it will behave. Little or no wind could cause the material to stay in the area and accumulate while high wind could cause the material to leave the area and increase the danger area.
4. Other hazards of the material?
- Based on research the hazards of the material may also assist in determining the level of personal protection and also the air monitoring strategy.
Case studies can also assist responders in determining their actions at their next hazmat emergencies. Careful analysis of how past incidents were handled and the lessons learned can greatly aid personnel in their decision making skills. Trial and error and experience are good teachers but it is far more prudent, and less dangerous, to learn vicariously. History has proven that some hazmat responses were handled poorly and some were handled well. Study of these incidents will only enhance the effectiveness of future responses.
A good example of a Chicken Little Syndrome of a hazmat emergency involves a low volume leak of sulfuric acid from a punctured drum on a flat bed truck on a busy interstate highway. The time is during rush hour on a Friday afternoon before a holiday weekend. The over-reaction and worst-case scenario to this situation would have the first responders and associated hazmat response team literally shut down the interstate in both directions and set-up a fairly large hot zone or exclusion area based on the hazards of sulfuric acid. Most likely the hazmat responders would suit-up in Level A all-encapsulating suits and enter the back of the truck to seal the leaking drum and maybe even over-pack it into a salvage drum. After the residual acid is neutralized and cleaned up the incident may be declared terminated and the truck and drum turned back over to the responsible party. Probably, after several hours the interstate may be opened up and traffic, backed up for miles, be allowed to travel through. Have you observed this happen before? Does it sound familiar?
A better way to handle the release above and avoid over-reacting is to initially analyze the incident. What is being released? A liquid. What is the material? Sulfuric Acid. What is the vapor pressure of sulfuric acid? Approximately 0.001 mm/Hg. This is extremely low which translates into virtually little or no vapors in the air. This means there would most likely be little or no risk of a toxic airborne exposure hazard. So, the major hazard of the leak would become a contact hazard to skin, steel, and other materials. Most likely Level B PPE would suffice in handling this release but the hot zone or exclusion area would not require a very large area. Most likely this incident would not require the shutdown of the interstate and the whole incident would probably only last less than one hour.
Now this is merely a fictitious incident and may be simplified but the point here is that the above sulfuric acid release can be handled very efficiently without compromising the health of the public, the environment, or the responders. The Chicken Little Syndrome can be avoided with prudent risk assessment practices, common sense, and based on past experiences, both yours and others.
