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Haz Mat "Specialist Course"
Thursday
Dec012016

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

Saturday
Nov052016

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

Saturday
Oct012016

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

 

Thursday
Sep012016

Foam 108.2 Wetting Agents

Class “A” (foam) is an incorrect term. Class “A” (Wetting Agent) should be the correct one. This is because operational personnel need to delineate the marked difference between classes “A” and “B”. This is akin to referring to all automobiles as “cars”. We know they are all transportation tools, but designed for quite different applications. You would not use a small vehicle to transport large amounts of equipment.

Class “A” Wetting Agents are degreasers designed to reduce surface tension of organic substances so that they can allow the water to “soak” in to these materials reducing the temperature and extinguishing the flames. Class “B” Foam uses the advantage of water surface tension to float across liquid surfaces forming a uniform blanket of finished Foam that also cools surface temperature but mainly provides a smothering affect extinguishing the flames and suppressing future vaporization of the hazardous product.

Herein lays the difference, these are two (2) opposing forms of chemistry that have opposite uses. Once this concept is firmly implemented into your response group, choosing the correct product to attack your hazard becomes simple!

Another factor to include in your operational program is one characteristic of “wetting agents” that is often over-looked. Since these liquids have degreasing properties, it is imperative that you appreciate these liquids are drying out your equipment. After use “re-lubrication” to your pump components, valves, nozzles, and any other appliance that the wetting agents flow through is imperative! Just like any tool, your equipment must have the proper lubrication to continue to function without damage. This is a separate subject that needs careful consideration by you and your equipment maintenance personnel.

If you use great amounts of these products, such as wild-land firefighters do, it behooves you to research these issues closely! Be proactive so that your equipment does not fail on you leaving you unprotected! Develop good relationships with your equipment maintenance staff and regularly discuss and refresh over these needs.

Class “A” wetting agent frequent use by your department should encourage you to have a vigorous relationship with your maintenance staff. Be sure that they too, understand the ramifications of continual use of these “wetting agents”.

The benefits of wetting agents can be seen in the “Foam 108 Class “A” Wetting Agents” article located in the left side-bar archive section of this website. They are numerous and useful as long as “you choose wisely” for the application needed.

                      Haz Mat Mike

Monday
Aug012016

Foam 107.2 Application Techniques

When we speak of the implementation of application techniques as we did in (see Foam 107 post) what we are really training the firefighter in is the “practical” application of these techniques. This requires actual hands-on suppression of flammable liquid fires using firefighting Foam and the techniques discussed.

If you do not have access to a training facility that is set-up for flammable liquid firefighting, this can be accomplished using a designated area and “pan fires”. Pans are constructed out of heavy gauge steel, welded at the corners to keep flammable liquids and suppression water confined.

To do this in your local area, apply for a Fire Department “Variance” through your local government and employ the talents of your own DPS (Department of Public Services). If these cannot be done, a trusted local welding contractor can fabricate your “pan”. For multiple students repeating a fire extinguishment, a good place to start is with a 4 to 6 inch wall to the pan. This will allow you many extinguishments without having to halt the training session to empty the pan level. Any size or shape can be made, but a good starting place is to make construction of the pan so that it fits inside a standard pick-up truck box. This makes transportation of your “burn pan” easy for multiple vehicles. One idea we added was to incorporate wheel casters into the fabrication design. However, extra sturdy and heat resistant casters must be used for extreme heat and use.

When teaching the three methods of Bounce off, Bank-In, and Rain down, you must key the avoidance of “plunging”. In all three methods, “plunging” of shooting a concentrated stream of firefighting Finished Foam into a flammable liquid pool will do two things;

1] Spray ignited flammable liquid into the air, thereby spreading the fire, ignition of exposures not currently involved in fire. This can also needlessly endanger nearby firefighters involved in your operation.

2] Plunging disturbs the flow of the Foam blanket which is what you are attempting to create. This “blanket” of solid finished Foam is what causes extinguishment by smothering and cooling of surfaces.

Bouncing Off

When teaching this technique, the most important factor is to use the “object” involved, as a deflector. The object is irrelevant, what is not is the idea and practical theory of breaking the solid stream so that the resulting Foam will “flow” across the pool where the majority of the flammable liquid fuel source is located. This cools and smothers the “feedstock” of the flammable liquid fire, soon to eliminate flame as soon as the fuel source is entirely covered.

Bank-In

When there are no deflectors or objects to “bounce-off” this method can be used by easily striking the ground in front of the flammable liquid pool. This action causes the finished Foam to pile up and form a wave-like roll of finished Foam that continues towards the pool and eventually overlapping the pool edge, continuing to flow across the pooled surface.

Rain Down

This method is primarily used for vertical storage tanks due to the configuration of these high walls. Often it is too hazardous to reach the top of these storage tanks and Foam application must be made from ground devices. Unfortunately, this technique requires larger Foam concentrate resources. Due to the “burn-back” and subsequent loss of Foam from passing through the fire and super-heated gasses, this technique requires longer application with greater volumes of Foam concentrate.

When using this operation, coordinate liquid levels with Tank personnel to be sure your Foam concentrate does not “drain-time” quicker than it extinguishes. If this is not figured in to your over-all attack plan your efforts could overflow the flammable liquid while it is on fire! Great care to watch and monitor tank levels must be made to avoid overflow and protect fire department personnel.

                     Haz Mat Mike