Search Past Articles
Explore Past Articles
Haz Mat "Specialist Course"

Foam 113.2 Foam "Fini"

We cannot complete our journey through Foam and Foam 0.2, without a look at the important concepts to remember. These are;

1] Chemistry

2] Extinguishment process

3] Vapor suppression

The chemistry of Foam use and its Physics are the most important to remember when choosing a system to adopt into your department responses. This is that the two opposite concepts of chemistry, one to float across the surface, and one to reduce surface tension, cannot both be effectively and safely used on different fire situations. When your organization is approached by the economic community representing the sale of these modern marvels, they should be scrutinized with a wary eye. What one principle favors, may dis-favor safety or personnel security.

Whether you desire extinguishment of fire, or vapor suppression of hazardous material fumes/vapors, these two emergencies require a separation of the fuel source from the flame, or the vapor from the atmosphere. In both cases, a Foam blanket, or barrier is the only way to halt the combustion or vaporization process. Dispersal, encapsulating, or dilution only cures the symptoms and not the disease. In these cases, you will wind up with a greater environmental hazard or lesser personnel safety for on-site responders, or in most cases, both! A successful extinguishment does not include a re-kindle due to an improper chemistry approach.

Lastly; vapor suppression includes combustion as well as hazardous material mitigation. In the case of combustion, blanketing separates the burning surface from the fuel source thus extinguishing. In the case of vaporization, eliminating the formation of toxic vapors shall allow for; in-place sheltering without the transportation issues with a full evacuation, lowering of toxic exposure and contamination of “affected” civilians, reduction of contamination to nearby environmental concerns all the way from personal Pets to local fauna and flora for quite some distance.

By using class “B” low/medium expansion concentrates and equipment techniques you can eliminate fire and hazardous vaporization. With class “A” agents, you can de-escalate wild land fires and reduce urban combustible destruction. You cannot do both with one. Each of these demonstrates this opposing chemistry and is why the NFPA has separated the Foam classes. Each one gives you the data to make the correct choice after reflection. These tools give you the ability for safe and successful incident mitigation.

Haz Mat Mike


Foam 112.2 Wildfire Foam Concentrate

The overall concept of wildland firefighting is to stop the progression of fire and to protect exposures from becoming involved in the existing fire. Class “A” wetting agents, frequently referred to as Wild Fire Foam accomplishes this through the action of “surface tension reduction.”

It is this one principle of physics that allow the entire system to “function” towards its desired result. The wetting agent mixes with the extinguishing water be agitation and thus reduces or “breaks down” the holding water tension which allows water in its natural state to bead on surfaces. This reduction also allows water to better “soak-in” all organic materials, like; trees, vegetation, houses, and any other structure constructed of wood or woody fibers. This fact affords the protection of civilians and the environment.

Environmental concerns must also be factored into this equation for the local emergency response to be successful. Unessential vegetation that frequently serves as kindling to major forest fires must be reduced through the practice of land management. Just as game animal populations are reduced through the practice of seasonal hunting, so to, should vegetation be reduced when located near or around high hazard areas such as residential homes. Grasses in the western states are a major culprit. Grass should be kept cut to a short length that will greatly reduce the spread of a wild fire. In many cases grass control fosters the growth of other plants that regularly may not receive a chance to grow and prosper in that particular area. This can enhance the local environment.

Time is a large factor for firefighting applications. When wetting agents applied are used with a CAFS (Compressed Air Foam System) a shave cream consistency is created. This consistency gives the longest time affordable to the applied wetting agents on surfaces. This factor facilitates equipment use being able to apply these wetting agents while keeping ahead of the fire geographically.

When used by mixing with standard booster tank water from a fire engine in a municipality situation, the wetting agent gives faster and more though rough soaking of combustible materials that may or may not be organic. In this mode, inner-city fire departments can accomplish faster knockdown times in urban settings. Wetting agents, AFFF, or class “A” wild fire type Foams can be used in this manner. This results in one product deployed by a variety of techniques accomplishing two (2) different emergency incidents. This product shows its versatility under different conditions.

Wildfire Foams and Wettings agents can be applied using common eduction devices or through more specific equipment. Always use the correct proportioning device for the desired Foam effect. Using the wrong application device for the wrong type of use you want to achieve is not recommended and easily avoided with manufacturer instructions and a few training evolutions. Prepare well ahead of your emergency so your equipment choices will be the proper ones for the affect you want to achieve.

                      Haz Mat Mike


Foam 111.2 Storage and Compatibility

          The compatibility of various Foam concentrates to be used together under standard applications during an incident is usually not a major issue. However, please note that if this becomes a situation where the incident need overrides prudence, there will be some performance issues. Mixing use of various Foam types is generally not recommended for this exact reason. But storage of these various types in the same container(s) is prohibited. This practiced is referenced many times throughout the literature and is a recipe for disaster. Foam concentrates are designed NOT to be stored in the same container as concentrate contamination will result. Opened containers not used on the incident are best used for future training evolutions. They should be used within the next training cycle as opened containers also have a drastically reduced shelf life for effective use.

          Tank materials, whatever the size also have issues. If you are removing concentrate from its original shipped container and placing it in a deployable equipment tank, all of the time regulated and atmospheric testing recommendations must immediately take effect. Be sure that you follow the manufacturer’s instructions for sample taking, lab testing, and tank lid securing to insure proper eduction and application during an incident. Lastly, older “galvanized” tank materials should NEVER be used for any type of Foam concentrate storage. This material causes sediment corrosion which will inhibit eduction and possibly cause harm to pump systems.

          Foam concentrate storage should be planned BEFORE tactics are placed in service. The key factors are;

          1] Storage location

          2] Storage temperature

          3] Container material

          4] Facility quantity

          5] Rapid repletion and replenishment

          By following these and the recommended practices for storage and compatibility from you manufacturer, the shelf-life of your Foam concentrate can be expected to be met, and in most cases, exceeded. These practices will ensure that during an emergency incident your Team will have a successful outcome.

                     Haz Mat Mike


Foam 110.2 Concentrate Labeling

While concentrate labeling may be slightly different for various sized Foam concentrate containers, keep in mind the “size” container you choose for storage and transportation. While firefighting and hazardous materials incidents usually restrict themselves to the 5 gallon pail, realize that they have a good source of manpower under a constant availability to move and transport all these containers. Departments that specialize in equipment handling as opposed to high volumes of manpower, can afford larger containers such as the 300 to 500 gallon “tote” or larger. All depending on how they can effectively move these concentrate containers to the desired incident site.

Regardless of size, all containers should have some critical information on them. Such as;

1] Percentage concentration

2] Performance standard certification

3] Health hazards

4] Use instructions

5] Storage instructions

          The percentage concentration is critical for proper use. Additionally, if Foam concentrate is used in tandem due to shortages or an event which is of long duration due to its intensity, your percentage on “eduction” may have to change. This is important for engineers to know when these changes affect them and the overall success of the incident. Eduction percentage must change the moment a different concentration is used for effective application of your finished foam blanket. These types of adjustments are the key to successful Foam concentrate integration during use.

          Certifications included by UL or FM insure the quality of product you are currently using. If these are not included, the quality of Foam concentrate you are using should be suspect. Quality reduction can result in a multitude of elements such as life safety, volume of concentrate needed for successful extinguishment, cost, and successful vaporization mitigation. All of these directly reflect on personnel safety and should not be taken lightly.

          Health hazards are not only needed for proper storage techniques, but also serve the immediate responder when specialized equipment is needed. Some may require the use of specialized protective equipment under extended use. Under either scenario, successful mitigation is not complete if your response personnel are placed at risk due to product exposure. Be sure your crew is properly outfitted for prolonged contact during handling of Foam concentrate.

          Use instructions are an obvious plus for members that may not have or had, extended experience with Foam application Training. Always be sure to have experienced engineers operating the pump panel and/or eduction when operating Foam operations. Inexperienced personnel are better suited to hand line operation or master stream devices during these incidents.

          Storage instructions are critical to ensure the “next” incident will make available Foam concentrate that will perform to your standards. Improperly stored Foam concentrate may not perform to a level that a successful mitigation requires. Proper storage (post or pre incident) should be viewed the same as proper maintenance to your Engine or “system”. Having these labeling requirements as a reminder, will enhance frequent Training, and insure a successful incident by your Team.

                         Haz Mat Mike


Foam 109.2 Blended Fuels

Blended fuels combine polar solvents with internal combustion fuels to create a homogenous mixture that reduces impact on our environment. Minimal separation reduces engine issues for prolonged storage inside fuel tanks.

The varying levels of percentage (%) combination of these polar solvents allow “tweaking” of fuel ratio concentrations for a variety of engines to reduce all emissions. These “varying” differences can have an impact on flammable liquid fire suppression techniques especially when Foam concentrates are being used.

The effect of varying concentrations of polar molecules to hydrocarbon fuels causes blended fuels to;

1] Burn hotter

2] Varying vapor pressure

3] Surface tension change

4] Polar attractiveness changes

The NFPA Foam application methods will have to accommodate these changes. When using any of the three (3) types, be aware of such variables as Foam reserve volumes, Foam concentrate type, and the design/purpose of the Foam concentrate you have chosen for your operation. Are you suppressing vapors or extinguishing flame? These may affect your operational procedure.

Having trained personnel as opposed to relying on a fixed system will increase your operational capabilities in most incidents. The trained operator can adapt to issues and concerns as he/she sees them forming to get the desired result. Keeping personnel “up-to-date” towards changes and new trends will ensure a successful mitigation outcome for your emergency.

                             Haz Mat Mike


Page 1 ... 3 4 5 6 7 ... 29 Next Entry »