      aA N                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                TYPE 3 2.00                                                                                                                                                                                             **2.00         Sodium Cyanide                            1                                                                                                                      ==============================================================================                                 SODIUM CYANIDE                                ------ -------                                By: Frank L. Fire------------------------------------------------------------------------------             Sodium Cyanide, chemical formula NaCN, is a toxic, reactive,      corrosive, deliquescent, nonflammable white solid (as granules,      flakes, or lumps) with a faint odor of almonds. It is used in the      electroplating of materials, metal treatment processes, gold and      silver extraction, and in the manufacture of dyes, pigments,     insecticides, fumigants, and various other chemicals.       PROPERTIES           Sodium cyanide will not burn, but it can be decomposed in a fire      and will produce carbon monoxide and a family of gases called the      nitrogen oxides.  It has a specific gravity of 1.6 and a molecular      weight of 49. It melts at 1,040~F, boils at 2,725~F, and is very     soluble in water.       HAZARDS            The major hazard of sodium cyanide is its toxicity in its own      right. An additional hazard is the reaction into which it enters that     produces the deadly gas hydrogen cyanide (HCN).          Sodium cyanide has a TLV-TWA (Threshold Limit Value-Time Weighted      Average) of 5 mg/m3 (milligrams per cubic meter of air) as cyanide.      Its IDLH (Immediately Dangerous to Life and Health) value is 50 mg/m3.      It is toxic by all routes of entry, and its LD50 is less than 50 mg/kg      (milligrams per kilogram of body weight). Hydrogen cyanide has a     TLV-TWA of 10 ppm (parts per million parts of air).          Sodium cyanide can be absorbed through the skin in amounts that      can produce fatal results. Contact with the skin can result in itching,     discoloration, dermatitis, and caustic burns.         Contact with the eyes can produce severe injury.          Inhalation of the dust in sufficient quantities will cause death      in much the same manner of indigestion. Small amounts can cause     irritation in the upper respiratory tract.          Very small amounts of sodium cyanide, if ingested, can cause death.      There may or may not be prior symptoms of poisoning, depending on      whether the victim has any other food in his stomach. Those symptoms      include weakness, dizziness, headaches, vomiting, convulsions, and     coma.          Although sodium cyanide is a stable chemical and dissolves rather      rapidly in water, it will, if exposed to moisture or small amounts of      water, liberate small amounts of hydrogen cyanide gas. If the water      is at all acidic - even slightly - hydrogen cyanide will be liberated     in large quantities.          It is well known (or should be) that hydrogen cyanide is deadly.      As a matter of fact, the original gas chambers used to execute persons      convicted of capital crimes were permeated with sodium cyanide and an      acid, usually sulfuric. One pellet (perhaps half the size of a small      hen's egg) of sodium cyanide was placed in each of two tubes that led      to a glass container partially filled with sulfuric acid. When a lever      was moved, the sodium cyanide pellets rolled down the tubes to the      container of acid, and the reaction was immediate. Hydrogen cyanide      was generated immediately and the chamber (an enclosed room) rapidly      filled with the deadly gas. Only a few short "whiffs" of hydrogen      cyanide are required to begin the convulsions, and death is fairly      rapid. Even if the condemned person could hold his breath (or wore a      self-contained breathing apparatus), the hydrogen cyanide would be      absorbed through the skin and death would still occur within ten     minutes.          Sodium cyanide will react violently (explosively) with any strong      oxidizing agent. Other reactions will occur with other chemicals, and      they may produce potentially poisonous substances. During      transportation and storage, sodium cyanide should be kept cool and      dry, and contact with the material must be avoided. Contamination      with oxidizers such as inorganic nitrates, nitrites, perchlorates,      chlorates, chlorites, hypochlorites, and permanganates must be      avoided, in addition to nitric acid, the halogens (flourine, chlorine,     bromine, and iodine), and any peroxide, organic or inorganic.      NONFIRE SPILL            Any spill of sodium cyanide will result in a powder, pellet, or      granulated material being released. In all spills and accidental      releases, the proper environmental authorities must be notified while     action is being taken to protect the population.          If the sodium cyanide is dusty, evacuation downwind must be      considered immediately. However, if the product is in a size that      would not be blown around, there is no danger of the spread of      contamination. No action should be taken other than securing the area      of the spill and keeping all personnel away from the material. The      seller, the shipper, and the consignee (the company to whom the      material is being shipped) must be notified immediately of the spill     so they can begin salvage and cleanup activities.          At no time should it be necessary for emergency response personnel      to get involved in the cleanup. If for some reason it does become      necessary for firefighters and/or other emergency response personnel      to actually handle the product, they must remember that they are     dealing with a deadly poison and protect themselves accordingly.          (It has been pointed out many times in this series that cleanup      and/or salvage should be done by professionals who are properly      educated, trained, and equipped. However, as a reader has recently      pointed out, some or these "professionals" are not always as properly      educated, trained, and equipped as they should be. This is probably      true, but it still is not the job of the fire service to involve      themselves in the cleanup, unless it is deemed necessary to protect      human life. If the environment is involved, the federal or state EPA      will see to it that the spill is properly cleaned up if the first      cleanup crew is not effective. But the point has been made: The      "pros" of salvage and cleanup may be worse than the amateurs. This is      not an indictment of professional salvage firms, but it is important      that the fire service get to know those firms before an incident      occurs and they are needed. To make sure the point of this "aside" is      not lost: The fire department should not involve itself in cleanup or      salvage operations after the conclusion of a hazardous-materials      incident. They may be asked to "stand by" to ensure that if the      incident reoccurs due to cleanup or salvage procedures, they may again      mitigate the incident, but that should be the extent of their     activities).          Since sodium cyanide is sensitive to moisture, it may be necessary      to cover the spill with a material that is impervious to water, such      as plastic or rubber sheeting. In any event, the approach to the      spilled product must be made with extreme caution and always from      upwind. If dust is being blown about, a water spray or fog will      dissolve it from the air. However, attention must now be paid to     confining the runoff water which has sodium cyanide dissolved in it.          If moisture does reach the spilled product, evacuation downwind      must be considered due to the danger of hydrogen cyanide evolution.      The hydrogen cyanide gas is just slightly lighter than air (the vapor      density of hydrogen cyanide is 0.931), and should dissipate slowly,     but chances cannot be taken with such a toxic material.          Entry of sodium cyanide into waterways and/or sewer systems must      be avoided. Entrances to sewers should be diked; if the product or      runoff containing the product does enter a sewer, the sewage treatment      facility must be altered immediately. If the product or runoff enters     a waterway, all downstream users must be notified.          The hazards of such contaminated water should be obvious to users      but may not be. Untreated water will be poisonous to anyone who drinks      it, but industrial users may not realize the danger. If water with      dissolved sodium nitrate were to enter an industrial (or other)      operation where it became acidic, large volumes of hydrogen cyanide     gas would be generated from the contaminated water.          If the product enters a waterway, it will sink to bottom and      dissolve rapidly. The only way to prevent the contamination from      moving down stream is to dam the stream or divert the water to      low-lying impoundment area. Manufacturers and/or users of the sodium     cyanide can then recommend action to neutralize the threat.          For released product in solution form, or where water was used to      dissolve the release product, containment ponds or pits can be      constructed to hold the liquid. Contamination is greater when the     dissolved product is involved.          Once a waterway has been dammed or diverted, or the dissolved      product has been contained in a pond or a pit, the liquid may be      siphoned or pumped from the building area into secure containers for      disposal. If the solid material or a solution of it  has been salvaged      and is to be disposed of, it must be done in accordance with federal,     state, and local regulations.          The dry product may be salvaged simply by shoveling or scooping     from the ground and transferred to secure containers. In any case, any    personnel involved must be protected from contact with the product.           FIRE SITUATION           Although sodium cyanide is not flammable, it can be decomposed by      high heat such as that produced by a fire. Whenever the material is      exposed to fire, carbon monoxide and the nitrogen oxides will be      formed. Carbon monoxide is flammable, and the amount generated from      decomposing sodium cyanide may not pose a hazard too much greater than     the CO from the fire.          However, the nitrogen oxides are another matter. With the      exception of nitrous oxide, the other nitrogen oxides (nitric oxide,      nitrogen dioxide, nitrogen trioxide, nitrogen peroxide, dinitrogen      pentoxide, and trinitrogen tetroxide) are quite toxic and do not burn.      The effect of nitrogen oxide poisoning is often delayed eight to 48      hours and may result in death. Naturally, the amount of nitrogen oxides      generated will be determined by the amount of the material exposed to      high heat, but the toxic hazards of sodium cyanide are so great that      all emergency responders must protect themselves from the material at     all times, whenever it is threatened by fire or not.          Care must be used in extinguishing a fire near sodium cyanide,      particularly if the extinguishing agent and/or the way it is discharged     might cause the material to spread.          When water is used, you must remember that sodium cyanide is      sensitive to small amounts of moisture, and it will dissolve in large      amounts. If any of the solid material begins to release hydrogen      cyanide, all emergency measures needed to prevent exposure to humans      must be taken. If large amounts of the gas are generated, an imminent     explosion hazard must be added to the toxicity hazard.          If enough water is used in fighting the fire to dissolve some or      all of the sodium cyanide, the runoff will become a hazard and must be      contained in containment ponds or pits. The amount of sodium cyanide      present and the amount that may be dissolved should be considered when      a choice of fire extinguishing agents is available. Forms, because      they are water-based, may provide just enough moisture to cause gas      evolution from the solid product but not enough water to dissolve it.      On the other hand, the use of a large amount of foam may blanket the      sodium cyanide and effectively reduce the release of gas to the     atmosphere.          Carbon dioxide, when discharged, might have enough force to spread     the solid material around, especially if it is in powder form.          If the release or spill of sodium cyanide occurs in a mixed load,      or if it occurs at a warehouse location, the other chemicals present      must be considered as adding to the danger. If any contact occurs with      the oxidizer, decomposition of sodium nitrate will accelerate. And if      any acid (even if diluted with water) comes in contact with the     material, the evolution of hydrogen cyanide will be very rapid.          It must be understood that a release or spill of sodium cyanide is      not necessary for the above-mentioned problems to occur. If sodium      cyanide is present in a mixed transport load or in a warehouse, it can      become involved in an incident simply by the nature of the incident.      In a warehouse fire, all sorts of chemicals may be released and come      into contact with sodium cyanide, even if it is in its original      container. This is only one reason why emergency responders must pay      attention to the MSDS or lists of chemicals provided under SARA Title      111. It is also important to preplan chemical warehouses so the      possibility of the presence of each hazardous chemical is known. By      studying all the MSDS's or chemical lists provided by industry, a      pattern will develop that will allow each fire department to preplan      even transportation accidents involving hazardous chemicals. This is      possible because the presence of these chemicals usually indicates      shipment into or out of the site where they are found (assuming they      are not intermediate chemicals produced on site for use on site).      Sodium cyanide presents such a major hazard that its presence with in      a fire department's protection jurisdiction must be known long before     it becomes it involved in an incident.          PROTECTIVE EQUIPMENT AND CLOTHING            Protective equipment and protective clothing chosen must prevent      all contact with the product, including eye, mouth, and skin contact.      Face shields and chemical splash-proof goggles must be used to protect      the face and eyes, and rubber aprons, gloves and boots may protect      other parts of the body. Any clothing impervious to water and dust      should protect a responder from contact with either the solid or      dissolved material. Since sodium cyanide itself is relatively      nonreactive (with some exceptions), any good chemical encapsulating      suit that is air-tight and water-tight should protect the wearer. SCBA     must be used in all incidents involving this material.          FIRST AID           For skin contact, all contaminated clothing must be removed, and      any skin that has come in contact with the product must be thoroughly      flushed with water, followed by large amounts of soap and water.     Medical attention is needed immediately.          In case of eye contact, flush the eyes with water for at least 15      minutes, occasionally lifting the eyelids. Get immediate medical      attention For ingestion, the victim must be kept quiet and warm.      Cyanide kits will provide sodium thiosulfate, and the victim (if      conscious) must be made to drink a pint of 1% solution of sodium      thiosulfate, which must be repeated in 15 minutes. Never try to make      an unconscious person drink anything. Immediate medical attention is     imperative.          If the victim has inhaled the dust or hydrogen cyanide gas, he must      be removed to fresh air and kept quite and warm. Immediate medical      attention must be sought. If the victim is unconscious, artificial      respiration should be administered, but care must be exercised to      protect the first-aid giver from the toxic effects of material in the      victims lungs and/or vomit. If a cyanide kit is available, amyl nitrate      should be administered per instructions (usually having the victim      breathe the vapors of a crushed ampule or pearl of amyl nitrate for      five cycles of breathing -amyl nitrate for fifteen seconds and air for      fifteen seconds). Oxygen must be administered once the victim is     conscious or trouble breathing.           The above was taken from:      Fire Engineering   July 1989     Chemical Data Notebook Series # 38