Spills chemical agents

This is a subroutine that calculates an evaporation rate from a pool of spilled liquid in presence of wind (ORG-40), or in still air (TP-10). It was developed by the U.S. Array for downwind hazard prediction following release from smoke munitions and chemical agents. The code calculates the evaporation rate of a liquid pool, given the physical stale variables, wind speed, and diameter of pool. ORG-40 and TP-10 models are coded as a Fortran 77 subroutine, EVAP4.FOR, in D2PC. The user s manual is Whiiacre (1987). 

There are some requirements that oil spill-treating agents should fulfill. Chemical dispersants are often used to disperse spilled oils, which threaten to... 

Dry chemical agents currently used are a mixture of powders, primarily sodium bicarbonate (ordinary), potassium bicarbonate (Purple K), monoammmonium phosphate (multipurpose). When applied to a fire they cause extinguishment by smothering the fire process. They will not provide securement of a flammable liquid spill or pool fire and it can re-flash after it is initially suppressed if an ignition source is present (i.e., a hot surface). Dry chemical is still very effective for extinguishment of three dimensional flammable liquid or gas fires. It is nonconductive and therefore can be used on live electrical equipment. 

The physical transport of oil droplets into the water column, called dispersion, is often a result of water surface turbulence but may also result from the application of chemical agents (dispersants). These droplets may remain in the water column or coalesce with other droplets and gain enough buoyancy to resurface. Dispersed oil tends to biodegrade and dissolve more rapidly than floating slicks because of high surface area relative to volume. Most of this process occurs from about half an hour to half a day after the spill. 

Acids such as sulfuric, hydrochloric, nitric, phosphoric, perchloric, formic, acetic, chlorosulfonic, 50% hydrofluoric, and adipic can be treated by a mix of magnesium oxide and other chemical additives. It must be expected that when the dry chemical agent is applied to an acid spill, there will be a momentary increase in the volume of vapor coming off the spill. This puff is caused by the heat generated from the neutralization of the acid. To protect the personnel applying the dry chemical cover from this puff, suitable personnel protective equipment should be worn. 

Decontamination solutions are dilute aqueous solutions of caustic or sodium hypochlorite. These solutions are used to wash (decontaminate) work areas where agent has spilled. They are also used to decontaminate a worker in PPE prior to removing the suit for disposal. Spent decontamination solution (SDS) usually contains very small amounts of the chemical agent breakdown products resulting from hydrolysis of the agent present on the surface being decontaminated. SDS is collected and stored on-site for later disposal either off-site or on-site by incineration. 

Dispersant— A chemical agent that reduces the surface tension of liquid hydrocarbons, encouraging the formation of an oil-in-water emulsion. This reduces the volume of residual oil on shorelines or the water surface after a spill. 

Between 7 47 PM on Dec 2,2000 and 12 56 AM on Dec 3,2000, three spill-pillows (each containing approximately 20 pounds of liquid waste) were processed. How much of that was chemical agent VX is unknown. The spill-pillows contained talcum powder and an amorphous silicate absorbent. The 5X treated remains of the pillows, cardboard mines, fuses, and kicker chutes passed through the DFS and the non-combustible ash exited the heated discharge conveyor (HDC) to bin 135. At 8 06 AM on Dec 3, 2000 bin 135 was placed in the staging area (outside primary engineering control) with the lid open to cool. 

A HazMat team evacuates five square miles of a city business district in response to a chemical spill. Ten city blocks away, a police special response team forms a perimeter around an office building where a terrorist threatens the release of a deadly chemical agent. Meanwhile, paramedics administer first aid to victims exposed to a possible vesicant. 

Dispersant is a common term used to label chemical spill-treating agents that promote the formation of small droplets of oil that disperse throughout the top layer of the water column. Dispersants contain surfactants, chemicals like those in soaps and detergents, that have molecules with both a water-soluble and oil-soluble component. Depending on the nature of these components, surfactants cause oil to behave in different ways in water. Surfactants or surfactant mixtures used in dispersants have approximately the same solubility in oil and water, which stabilizes oil droplets in water so that the oil will disperse into the water column. This can be desirable when an oil slick is threatening a bird colony or a particularly sensitive shoreline. 

Solidifiers — These are a type of chemical spill-treating agent that are intended to change liquid oil to a solid compound that can be collected from the water surface with nets or mechanical means. They consist of cross-linking chemicals that couple two molecules or more to each other. 

Public Health Impacts If chemical agents are released, severe human health effects could result. The magnitude of the impact would depend on a number of variables the amount and type of agent released the method of release (e.g., spill, explosion, etc.) meteorological conditions the number of unprotected people potentially exposed to the agent(s) ... 

DETERMINATION OF EFFECTIVENESS OF SPILL CONTROL AGENTS IN MITIGATING VAPORS FROM HAZARDOUS AND TOXIC CHEMICALS ... 

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