It’s an ordinary day at the plant fire station. Your plans include maintenance on one of the units and a few other chores that have been needing attention — a routine day in the plant at Smalltown. Routine, that is, until the phone rings or the radio cuts in with an urgent message from the Chief of the Smalltown Volunteer Fire Department. There has been a derailment and they need help. There are several tank cars off the rails, a number of which are leaking copiously and feeding the fire which is growing in intensity. The railroad has been notified and their response team is en route but their ETA (Estimated Time of Arrival) is four hours. You are the only industrial fire department within a hundred miles. Can you help? “No, we don’t have any idea what the what the lading of the tank cars is.” You hit the alarm switch, climb on the apparatus and off we go to the races.
This is not an uncommon scenario and it is likely to become more common as industry continues to decentralize operations and embraces the “just in time” model for manufacturing and distribution. This ability to move merchandise and materials rapidly to any part of our country, and indeed the entire North American continent has created an unprecedented transportation system of a magnitude far exceeding that of any other industrialized society. The is not the result of happenstance but of necessity. The settlement of the vast open spaces of the American West at the close of the Civil War would have been impossible had it not been for the transcontinental railroad and indeed, this asset was a factor in the preservation of the union. Those who would peruse American history will find that, after 1865, the ability to move great quantities of men, equipment and supplies rapidly has been a major factor in all of the military endeavors in which we have been engaged.
The transportation of hazardous materials, literally from one end of the country to the other, exposes every community to the dangers inherent in such commodities. When an incident occurs, the preferred response protocol is to call the shipper. Sometime you call the manufacturer. After all, who knows more about the properties of a given commodity than the people who made it?
Unfortunately the “Law of Unintended Consequences” has not been repealed, thus the response time to an incident occurring at some isolated spot in the hinterland, far removed from any airport or interstate highway, may be long indeed. As a result, local emergency response organizations are often called upon to respond to incidents they know little about and for which they have neither equipment or training; but they answer the call and do what they can to preserve life and safeguard property. Americans have always been a sharing, caring people. From the earliest frontier days to the present, they have joined in communal efforts to assist their neighbors in times of adversity. One has only to listen and watch the recent television reports of severe weather damage to verify. This willingness to help one’s neighbor is not limited to the civilian sector; industry too is known for its willingness to band together in the interests of the common welfare. The mutual aid organization among the installations along the Houston Ship Channel is, perhaps, the premiere example. Thus it is no surprise to see the response team from the Smalltown plant heading out to the derailment site to do what they can to mitigate the danger, preserve life and minimize property damage until the “big boys” arrive on the scene.
The problem with this response scenario is that the Smallville plant makes “trimethylmotherinlaw” while the lading that is leaking is “diethylbadstuff.” The Smallville folks are well equipped and well trained in handling their product but they really do not know much about other commodities that they might encounter. Furthermore, they cannot be sure exactly which material is involved in the incident. Is it toxic, corrosive or unstable? What are its combustion products and are these toxic, carcinogenic or both? Will they react with other materials to form a third entity? All these things and more are legitimate questions for which the “foreign” responder wants, and needs, answers but these may well have to await the arrival of responders from the railroad or from the manufacturer. If a response team from the manufacturer of the material in question is present they could most likely provide the information immediately. They would have any requisite instrumentation and protective gear suitable for use with its product. Unfortunately, we are unsure at this time what is leaking and which manufacturer or shipper would be responsible. If there is a third party, such as a broker or cutting house, is involved the information trail becomes even more convoluted.
If the scenario involved shipment by motor truck, the situation becomes even more difficult. While many hazardous materials are shipped in truck load lots (either in tanks or in hoppers), many are not. These are usually loaded into box trailers as part of ‘General Freight,’ and there is no way of knowing what the accompanying shipments might contain in the way of potentially hazardous materials. These ‘General Freight’ trailers give local responders gray hair. Because of the extreme diversity of shipments as well as their size, few motor carriers are able to provide response teams trained and equipped to handle specific products. Furthermore, unlike railroad companies which own the entire railroad, rolling stock, the right-of-way and are the employers of the operators, motor truck companies often use contract owner/drivers who are independent businessmen. They simply show up at a designated location, hook on to the waiting trailer and depart en-route to the address appearing on the bill of lading. Often these drivers have no real knowledge of what they are carrying.
In any case, the Smallville response team is going to have its hands full. Like it or not, they are in charge until assistance from the railroad, the shipper or both can arrive. To fill this role in a manner that safeguards the response personnel, protects the environment and does not exacerbate the problem requires certain basic information which can be obtained even in the absence of response personnel specifically trained and specifically equipped to work with the material in question.
One of the first things that the responders from the Smallville plant need to keep in mind is that they are there to keep the situation from getting worse and protect life and property, not to remediate or clean up the spill. Of course, if one can stop the escape of a hazmat by simply shutting off a valve, applying an over-pack or plugging a punctured drum, wonderful. But remediation is not the main objective. Preservation of life and the protection of property and the environment takes precedence. Smallville responders are there simply to “hold the fort” and prevent worsening of the incident until representatives of the responsible party(s) arrive.
As Smallville rolls up on the scene of the incident, there are a number of things that can be done to assess the situation. People are born with five senses that are better than any man-made warning system yet devised. Use them. Approach from up-wind if at all possible. Turn off the air conditioner and open the windows.
If you smell the odor of bitter almonds, STOP immediately. This is the odor of cyanide or hydrocyanic acid (HCN). Retreat at once. Remember that the ability to smell cyanide is an inherited characteristic. Not everyone will detect the odor. If one smells the odor of rotten eggs, that is hydrogen sulfide (H2 S). If you detect the odor of household bleach, chlorine (Cl2) is indicated. The odor of “household ammonia” indicates the presence of ammonia (usually as anhydrous ammonia, NH3), a common agricultural fertilizer and industrial raw material. A sharp acrid odor is often associated with hydrogen chloride (HCL) or hydrochloric acid (often known as muriatic acid). A suffocating odor, often accompanied by a cloud of reddish “smoke,” (oxides of nitrogen (NOx) is often indicative of nitric acid (HNO3 ). The red vapors often indicate that a reaction is occurring between the nitric acid and a “red metal” (copper, brass or bronze).
The physical appearance of the containers involved is also a clue to the contents. A tank with rounded ends and a pressure relief valve on top indicates a high pressure gas. If the tank is equipped with brass (or other “red metal”) fittings, this is indicative of a gas such as propane or butane. Ammonia would (or should) not be loaded into such a container.
A tank (particularly a truck trailer) with a “tombstone” structure on top of the tank to protect the valves is indicative of an acid. In the case of railroad tank cars, a white tank with a black or brown band around the middle is also indicative of an acid. If the band is black the acid is most probably sulfuric, nitric or hydrochloric. If it is brown, the lading is hydrofluoric acid or hydrogen fluoride (HF). This is potentially one of the most dangerous commodities in general commerce and requires specialized protective gear and trained personnel for remediation. The brown paint used to make the central band around the tank will turn bright orange in the presence of the slightest leak and, for this reason, is used as a leak detector. If there are no leaks (as indicated by the lack of orange areas in the brown paint) the best course of action is simply to isolate the container and leave things as they are until specialized assistance can arrive on scene.
Tank cars utilized to carry sulfuric acid in high concentrations (above 70 percent H2 SO4 ) will be steel since sulfuric acid in high concentrations will not react readily with such tanks. Below 70 percent the tank will be lined with lead. Cars containing hydrochloric acid will be lined with rubber. When a defect develops which allows the acid to get between the rubber and the steel outer wall of the tank, the acid will eat through the metal in short order causing a major leak.
Ears are an important source of information and warning of impending danger, use them. A hissing sound emanating from a container is indicative of gas leaking from a pressurized container. A frying sound may indicate an arc caused by a damaged electrical system. A bell, buzzer, flashing light or other alarm device indicates a malfunction of a refrigerated shipping container, or an accumulation of carbon monoxide (CO) or other flammable and/or toxic gas. Remember that gasses such as carbon dioxide (CO2), nitrogen (N) argon (Ar), while not in themselves toxicor flammable, can displace atmospheric oxygen in an enclosed space creating a lethal atmosphere. Breathing apparatus is essential.
The reader will note that so far in this discussion there has been no reference to placards or labels; this is by design and there are two reasons for this. In the first place placards are all too often vandalized, burned, or obscured. This is, of course true also of painted labels such as “Anhydrous Ammonia”. In the second place one has to be in close proximity to read the number on a placard and history has taught repeatedly the wisdom of the axiom “If you don’t know, don’t go; it may blow”. This is where a good pair of binoculars or a spotting scope (available at most sporting goods stores) or even the telescopic sight on a deer rifle is invaluable.
Another clue available without the aid of sophisticated equipment is the appearance of the container. If Smallville is responding to an incident involving an “orphan” drum (one that has fallen unnoticed off a passing truck, for example), look at the surroundings. If the drum is badly rusted, vegetation is growing up around it and there are numerous “wigglers” (mosquito larva) moving around inside, it is very likely that the item has been there for quite a while. It might be assumed that the contents are not especially toxic and that the contained liquid is probably little more than accumulated rain water. However, don’t count on it; be careful. If the heads of a drum or other container have bulged outward we may be certain that the container was, at one time, under pressure and it may still be. As always, caution is the watch word.
After assimilating and assessing the information obtained at a safe distance through our senses, we need to determine exactly what material we are dealing with. If it is burning, flammability is self-evident. This will, of course, rule out a large number of chemicals or compounds. If it is not burning and there is no flame present, the material may indeed be flammable but not yet been ignited. Such a scenario might be encountered in the event of a leaking LPG tank, a ruptured gas line or a broken fuel line on an involved vehicle.
To characterize a spilled hazmat, a number of “quick, cheap and dirty” wet chemical tests may be employed. There are a number of commercially prepared kits on the market that can be used if they are available but the First Step Kit developed by the Washington State Department of Ecology Spill Response Section1 is probably the most cost-effective and is offered here as appendix I. This kit is composed of items commonly available from local hardware stores or pharmacies, though a few may best be obtained through local high school or collegiate chemistry department. The reagents employed are reasonably safe. The following are the tests utilized to determine the chemical character of a test sample2.
Presence of Water
Any commercially available test paper may be used or a homemade variety can be produced by soaking a strip of laboratory filter paper (coffee filter paper works just as well) with an aqueous solution of cobalt chloride. This solution should be close to saturation. The strips are then dried in an oven (215 degrees F) and stored in a sealed container. The strips should be blue in color. If water is present, the blue color will change to purple and finally to pink. A “water finding” paste, available from oil field supply houses may also be used.3
Water may be present in two ways: it may be a chemical component of the material being tested, for example rubbing alcohol (70 percent) or it might be present as a contaminate in a tank containing a water immiscible liquid such as kerosene or diesel fuel where it will form a layer on the bottom of the container. A thin film of “water finding” paste applied to a rod inserted into the liquid, to the bottom of the container, will show through a color change the level of the water interface. Note also that carbon disulfide, used as a solvent and a common article of commerce, is heavier than water. Therefore it will be found floating on water in contrast to the usual situation.
This test will give a number of false positives with materials such as methanol, but if the First Step protocols are followed additional tests will help to eliminate these.
Water Solubility and Reactivity
Add a small amount of the unknown to a test tube containing about ¼ inch of water and look for the following results:4
● The unknown completely dissolves in water. This indicates a polar solvent, an aqueous solution (salt in water). Solids that are soluble are usually inorganic salts or polar organics.
● The unknown is insoluble and floats on water. These materials are usually hydrocarbons and oils; they may also be flammable.
● The unknown is insoluble and sinks (nonpolar). These compounds are usually chlorinated hydrocarbons (or mixtures thereof such as dry-cleaning agents (trichloroethylene, tetrachloroethylene), PCBs or carbon disulfide (CS2). Note again carbon disulfide will float on water and it is flammable, Insoluble solids: If a solid material does not dissolve in water, the specific gravity is usually not important. Heating the sample gently may aid solubility. If the unknown effervesces (generates bubbles) generates heat or produces another product (a precipitate) or gas the unknown is water reactive. For test limitations refer to the First Step Kit procedure manual (Appendix 1).
Apply a small drop of the unknown to a piece of commercial pH test paper and compare the color with the chart supplied with the test paper. Colored samples or highly corrosive ones may have to be diluted with water and retested with fresh test paper.
Another trick which the author gleaned from the school of experience is the use of red cabbage juice an indicator of pH. This is another “quick, cheap and dirty” protocol, but it will work. In some instances, it is very useful for tracking spills and evaluating runoffs.
Obtain some red (or purple) cabbage. Remove the core and chop fine. Place in a blender with a small amount of distilled water and macerate at high speed as much as possible (the greater the degree of maceration the better). Place the macerated cabbage under a Liebig condenser and reflux for thirty minutes to an hour with methanol (ethanol may also be used). Alternatively one can use water but the boiling takes longer and the product is not quite as effective.
After reflux, the product is filtered through filter paper or coffee filter and diluted to twice its volume with water (In many cases, particularly when using methanol, the product may be diluted much more; determine the optimum dilution of each batch by trial and error).
To demonstrate the effectiveness of the cabbage extract, set up a series of test tubes containing about ¾ inch of water. To the first tube add a couple of drops of “household ammonia” or a tiny bit of lye (a fairly strong base). To the next tube add a small amount of washing soda, to the next one a small amount of baking soda, the next tube gets two drops of household bleach (Clorox), the next tube gets a small amount of vitamin C (ascorbic acid), the next one gets two or three drops of lemon juice (citric acid) the next gets two drops of vinegar (acetic acid) and the last one gets two drops of battery acid (sulfuric acid) or muriatic acid (hydrochloric acid). Each tube then receives two drops of the cabbage extract. If everything works as it should, the tube with the lye or ammonia will be blue in color and the colors will progress from blue, to green, to yellow, to orange and finally to red.
This reagent can be made up in large lots and, when dispensed from a squirt bottle, is a very useful tool with which to track contaminated runoff.
A piece of test paper prepared by saturating it with solution of potassium iodide and starch (usually potato starch) is wet with 3N Summer 2015 35 hydrochloric acid (commonly known as “Dilute”). Next a drop (if the unknown is a liquid) or a small smear (in the case of a solid) of the unknown is applied to the test strip. A color change from white to black, brown or blue indicates a positive result i.e.; the unknown is an oxidizer.
Wet a piece of lead acetate paper with distilled water. Apply a drop of the unknown. A color change from white to black or brown indicates the presence of sulfides. Weak sulfides may require several minutes for the color change to appear and colored samples may make reading the test difficult.
An alternate technique for this test that is particularly useful in the case of confined spaces, such as sewer manways or tanks, where the presence of hydrogen sulfide (H2 S) poses a definite risk, is to attach a small weight to the bottom of a line and then fasten a piece of paper towel to the line a few inches above the weight. In use, the paper towel is saturated with a strong aqueous solution of lead acetate (Pb(CH3 COO)2 ). The line is then lowered into the enclosed space with a swinging motion until the terminal weight contacts the surface of any liquid at the bottom. If such a liquid is present the surface will be visibly disturbed. At this point, the descent of the line is halted and the test paper is allowed to remain in contact with the atmosphere for several minutes. A color change from white to black or brown indicates the presence of sulfides and, in this case, the presence of hydrogen sulfide (H2 S).
WARNING!! This test procedure may generate hydrogen cyanide gas (HCN). SCBA should be worn and bystanders kept at a safe distance.
In a test tube containing a small amount of unknown (about ¼ inch) add two drops of concentrated sulfuric acid. Immediately thereafter insert a strip of cyanide test paper such as Cyantesmo® paper, (Gallard Schlessinger, Inc.) so that there is at least an inch or more of dry paper above the liquid level in the test tube. If cyanide is present at a level above 50 parts per million (ppm), the paper will turn blue in the zone just above the liquid where it is reacting with the evolved hydrogen cyanide gas.
Test limitation: the test paper is sensitive to cyanide concentrations as low as five ppm; however, it may take up to four hours for the blue indicating color to appear at this concentration. If the pH of the unknown is below 7.0, there is little reason to run the cyanide test.
Again, consult the accompanying manual for complete test protocol and interpretation of results.
This is a rough test for flammability and combustibility but it does provide an approximation of the flash point of the unknown material. Apply a portion of the unknown onto the looped end of a length of cool clean copper wire (ordinary electrical wire is satisfactory)
1. Using a propane blow torch (available from any hardware store) as a source of heat, bring the sample on the wire loop close to the flame (about ½ inch away) but do not touch the sample to the flame. If the sample ignites, it is extremely flammable and the flash point is probably less than 100o F.
2. Briefly touch the sample to the flame and remove. If the sample ignites and sustains combustion readily it is flammable and the flash point is probably between 100-140o F
3. Hold the sample in the flame for about 2 seconds and remove. If the sample remains burning after it is withdrawn then it is borderline flammable/combustible and probably has a flash point between140- 200 degrees F.
4. Hold the sample directly in the flame. If the sample will only burn while held directly in the flame or requires greater than two seconds in the flame to sustain combustion, the unknown is combustible and the flash point is probably greater than 200 degrees F.
Flash points are estimations only and interpretation depends on the individual running the test.
Beilstein Test (for Halides)
This test, performed simultaneously with the flammability test. It is subject to several limitations chief of which is the masking of the generated colors by other elements (particularly sodium).
To perform the Beilstein test copper wire is heated to redness and held in the flame until all contaminating and interfering elements burns away. If contamination persists, snip off the end of the copper test wire and start afresh. Then the wire is dipped into the unknown or a small amount is scooped up on the end of the wire. This sample is introduced to the flame and imparts color to it. The test may be repeated as needed to confirm results. Positive results are indicated by the following colors imparted to the flame.
Chlorine (Cl), Copper (Cu), or Boron (B)
Lithium (Li), Calcium (Ca) Strontium (Sr)
Sodium (Na) Lavender: Potassium (K)
Lead (Pb) Zinc (Zn) Arsenic (As)
These colors are unique to each element and the experienced operator should be able to differentiate between the red of calcium and that of lithium or strontium or the various blues generated by lead, zinc and arsenic. Viewing the flame through a filter of cobalt blue glass will aid in the detection of Potassium by blocking out the strong yellow/orange flame emitted by sodium which is usually present and often masks the lavender of potassium.
Iodine Saturation Test
This test estimates the degree of hydrogen saturation of an unknown and is only performed on a liquid sample with solvent characteristics.
The test is run by adding a very small (about the size of a pin head) crystal of Iodine to a test tube and then adding about ¼ inch of the unknown liquid sample. The results are seen as a color change.
● Alkenes (double bond compounds)
● Aromatics (benzene, toluene, styrene, xylene)
●Chlorinated compounds (TCE trichloroethene, PCE, tetrachloroethene, chlorobenzene and oils such as transformer oils containing PCBs or turpentine.
● Alkanes, hydrocarbons (saturated compounds) ● Thinners (kerosene, stoddard solvent, hexane)
●Chlorinated compounds (carbon tetrachloride CCl4 ,trichloroethane, methylene chloride CH2 Cl2 )
● Oxygenated and polar compounds
● Alcohols (methanol CH3 OH, ethanol C2H5 OH, isopropanol C3H7OH)
● Ketones (acetone C3 H6 O, methyl ethyl ketone (MEK) CH3 C(O)CH2 CH3.
● Acetates (ethyl acetate C3H6 O) Brown/Muddy indicates:
● Mixtures of two or more compounds such as gasoline. Limitations: If too large a crystal of iodine is used, any compound or mixture tested will turn deep red.
The Char Test is useful in determining whether the unknown is organic or inorganic. Begin by placing about ¼ inch of sample (solid or liquid) in a test tube. Heat the sample slowly attempting to either boil off the liquid or charring a solid. If vapors are given off, attempt to ignite them to determine whether they are flammable. Several differing results are listed below:
● Vapors that ignite - typical of organic liquids (solvents)
● Vapors that do not ignite - typical of water (solution)
● Charring residue - typical of dissolved organics ● Non-charring residue - typical of dissolved inorganics. Solid samples
● Vapors that ignite - typical of organics
● Vapors that do not ignite -typical of inorganics
● Charring residue - typical of organics
● Non-charring residue - typical of inorganics Subliming solids
● This discussion is not intended to impart all of the information Can be either organic or in organic (examples include naphthalene, phenol, sulfur and ammonium salts).
Included in the First Step manual is a report sheet which has been designed to assist the user to assess the information he/ she has gathered and come to some reasonable conclusion as to the character of an unknown. If a responder performs all of the ten tests outlined and records the results on the “score sheet,” it should be possible to provide those in charge with some idea of what it is that confronts them or, in some instances, assurance that they are not dealing with some exotic and dangerous material. Sometimes the knowledge of what is not present can be as helpful as what is in place.
This work is intended to introduce some of the simpler “wet” chemistry tests which can be performed in the field and will provide the user with a means of characterizing an unknown with the use of specialized (and usually very expensive) test equipment. The test kit can be assembled in a small tool box at a very reasonable cost as compared to conventional instrumentation; it has a long shelf life and relatively little operator training is required. It is recommended, however, that anyone attempting to deploy the kit make a number of “dry runs” to become familiar with the tests and their evaluations.
EPA Region 10 now utilizes this kit as a standard method and this might well be a good source of training for response personnel. EPA Region 6 (Arkansas, Louisiana, New Mexico, Oklahoma and Texas) can be contacted at: 1445 Ross Ave, Dallas, TX 75202 (800) 887-6063.
1. Copies of the First Step Kit Procedure Manual may be obtained from: Washington State Department of Ecology Spill Response Section, 300 Desmond Drive, Lacey WA 98504. Tel. (360) 407-6974 Used by permission
2. In all cases where water is called for, distilled water (from the food store is fine) should be used.
3. The protocol for making test strips and the use of “water finding” paste are tricks gleaned from the oil fields in Texas and New Mexico and added by the author. They are not part of the First Step Kit.
4. For complete details of the test procedure see Appendix 1
An accompanying manual with complete test protocols and interpretations of results can be found at fireworld.com/Archives/ tabid/93/articleType/ArticleView/articleId/96490/HazardCategorization.aspx
See all comments