The Westinghouse Air Brake Company (WABCO) conducted tests to simulate the train's airbrake system reaction to the brake applications as described by the engineer. Additional tests were also made using various brake applications to simulate a burst air hose and excessive trainline leakage. These tests indicated that brake applications as recalled by the engineer would have stopped the train before it reached the point of derailment. Only when the brakes were released after each application was there an indication that the train would have continued through the derailment area. With brake application, release, and application again before the air pressure in the trainline was adequately replaced, the braking ability of the train would have been reduced. (See appendix H.) The WABCO tests also showed that the lead cars had more braking than the rear cars. This condition would have allowed the rear of the train to continue moving momentarily faster than the lead portion at the point where the engineer released the brakes as the train left the 3° curve. Other Information Of the eight different products involved in the derailment, five were shipped under DOT hazardous placards: anhydrous ammonia, a nonflammable gas; acetone, a flammable liquid; methyl alcohol, a flammable liquid; chlorine, a nonflammable gas; and carbolic acid, a class B poison. Also involved were one car each of urea, sulfur, and carbon tetrachloride. Anhydrous ammonia.-Anhydrous ammonia is shipped liquefied under a DOT green placard, "nonflammable gas." The threshold limit value (TLV) or the average concentration to which persons may be exposed for ammonia is 50 parts per million. 7/ Anhydrous ammonia is a liquid which at atmospheric pressure boils at -28° F. The ammonia will remain in a liquid state when the temperature is above the boiling point if it is contained under pressure. If the pressure is removed when the temperature is above the boiling point, the liquid will be converted rapidly into a gas. This conversion results in rapid cooling of the commodity. When vaporized, 1 part by volume of the liquid becomes 855 parts by volume of gas. To conserve space, the commodity is loaded in tank cars as a liquid under pressure. If, after the ammonia is loaded, the temperature rises, some of the liquid will be converted to a gas which will increase the pressure within the tank and maintain the remainder of the commodity in the liquid state. When the ambient temperature reaches 70° F, as it did on the day of the accident, the pressure necessary to retain the anhydrous ammonia as a liquid in the tank is about 90 psi. The release of the ammonia gas resulted in heavy fog saturated with aqueous ammonia, and in the presence of chlorine produced ammonium chloride, which contributed to the heavy fog density. Carbolic acid.--Carbolic acid is shipped under the DOT placard, "class B poison.' ." The threshold limit for carbolic acid is 5 parts per million. As defined in 49 CFR 173.343 class B poisons are substances, liquid or solid (including pastes and semisolids) other than Class A poisons or Irritating materials, which are known to be so toxic to man as to afford a hazard to health during transportation; or which, in the absence of adequate data on 7/ American Conference of Government Industrial Hygenists. human toxicity, are presumed to be toxic to man [because Carbolic acid is an aqueous solution of phenol, which is one of the most poisonous of the common industrial chemicals. Phenol melts at 108° F and has a relatively high ignition temperature of 1,319° F. Symptoms of phenol poisoning include nausea, vomiting, dim vision, ringing in the ears, paralysis, and coma. Once absorbed into the body phenol can have severe systemic effects. Fires involving phenol are best fought with large amounts of water spray and wearing clothing impervious to vapors. Additionally, runoff waters must be confined to prevent contamination. This chemical has a distinct odor of a disinfectant. Chlorine.-Chlorine is shipped liquefied under the black-and-white DOT placard, "chlorine." The TVL for chlorine is 1 part per million. It is liquefied under moderate pressure, or when cooled to -30° F. When vaporized, 1 part by volume of the liquid becomes 457 parts by volume of gas. Upon release, chlorine gas produces a greenish-yellow gas that is 2 1/2 times heavier than air. Gaseous chlorine is highly toxic and irritating and on exposure combines with moisture in mucous membranes to form hydrochloric acid. Carbon tetrachloride, sulfur, and urea.-This group represents products with the ability to rapidly disperse combustion gases in fires with various levels of toxicity. As such these chemicals pose far greater toxic risks than as a fuel for fire. For example, carbon tetrachloride in a fire will decompose to phosgene, a class A poison (TLV = 1 part per million), sulfur into sulfur dioxide (TLV = 10 parts per million), and urea into nitrous oxides (TLV = 5 parts per million). These liberated products during a fire quite readily react with oxygen and moisture within the respiratory system and decompose into an acid. Small quantities of sulfur and carbon tetrachloride are regulated for passenger transport and as such are shipped under DOT placard, "Otherwise Regulated Material (ORM)," because the properties of these compounds are such that each compound can cause extreme annoyance or discomfort to passengers or crews in the event of leakage during transportation. When not transported in conjunction with passenger transport, these products are not recognized by DOT in the "quantity and form" in which transported to present an unreasonable risk; consequently, these chemicals are shipped exempted from 49 CFR requirements. Acetone and methyl alcohol.--Both of these chemicals are examples of products which present a far greater threat in a derailment as a fuel in a fire than as a toxic substance. Both of these products are shipped under a red DOT placard, "flammable liquid." Acetone vapors have a TVL of 1,000 parts per million and methyl alcohol has a limit of 200 parts per million. In fires these products liberate combustion gases and smoke. Acetone burns with a characteristic orange flame and methyl alcohol with a less colorful light-blue flame. Emergency response.-During the hours following the accident various Federal, State, and private response teams arrived at the scene. These teams represented the U. S. Environmental Protection Agency (EPA), the U.S. Coast Guard, the Florida Civil Defense, the Florida Department of Transportation, the FRA, the Safety Board, the AAR's Bureau of Explosives, the Dow Chemical Company, Georgia-Pacific Corporation, Air Products and Chemicals, Inc., of Penascola, the L&N, and the L&N's wreck removal contractor. Many of these teams responded on their own or were dispatched to the scene by someone who was not in command of the operation. During the arrival of these teams, local Crestview officials who had taken initial steps regarding evacuation and firefighting sought a person who might have overall charge of the response teams and who could advise them about what to do about evacuations, control of the fire, and removal of the wreckage. Most of the groups involved, however, had only accident investigative authority or were product-handling specialists. As a result of an earlier derailment in the area, the Crestview and Okaloosa County officials had formulated their own contingency plan, so they used it during this emergency. In the confusion of the early hours of the emergency, the first chlorine specialist team was turned back by local officials when they learned the team was en route. When an incident occurs that might cause pollution of waterways and coastal areas, the EPA and the Coast Guard have some coordination responsibilities. According to the National Oil and Hazardous Substances Pollution Contingency Plan (40 CFR 1510) (see appendix I), the EPA or the Coast Guard is responsible for sending an onscene coordinator (OSC) to an accident involving inland waters to see if the party responsible for the discharge is taking proper action. The EPA or the Coast Guard also must provide a chairman to head an advisory regional response team (RRT). The RRT, comprised of Federal and State agencies, serves as the body for coordination and advice during a pollution discharge. According to 40 CFR 1510.34, the agencies are supposed to have predesignated members serve on each RRT. During a pollution emergency, the members of the RRT ensure that the resources of their agencies are made available to the OSC. The RRT is activated as an emergency response team when a discharge involves a significant number of persons or regionally significant amounts of property. The RRT, with the EPA's OSC as chairman, was convened in Crestview at 9:45 p.m. on April 9, 1979, with volunteers from the responding agencies and companies. The volunteers were not predesignated as required by 40 CFR 1510.34. The RRT immediately began reviewing L&N plans for the hazardous materials removal and wreck clearing. It was not until this time that local officials knew what to expect regarding outside assistance. The RRT approved the L&N plans on April 10. The RRT was disbanded and the OSC left the accident site on April 14. The National Response Team (NRT) (40 CFR 1510.32), as part of its "continuing evaluation of response actions," issued a report on the RRT/OCS activities at Crestview. 8/ ANALYSIS The Derailment was When train No. 403 was switched at Goulding Yard into a 7,550-foot-long train of 114 cars with cars with an estimated weight of 10,628 trailing tons, it similar in length and weight to other trains that the L&N occasionally operated 8/ National Response Team Review of RRT-OCS Activities, Crestview, Florida, Train Derailment, Document Number 16450/4. between Pensacola and Chattahoochee. Consequently, when the five locomotive units were coupled to the train, the L&N employees probably were not overly concerned about the train's tonnage and the adequacy of the locomotive power since the total listed tonnage rating of the units was 10,663 tons. Also, the L&N operating rules or special rules covering train makeup and handling did not limit the length or tonnage of trains between Pensacola and Chattahoochee. A major problem with unlimited train length and tonnage is the difficulty of taking into account the numerous combinations of grades and curvature of track over which a long, heavy train will operate. When grades are 1 percent or greater and curves are as sharp as 4°, resistive forces that the locomotive must overcome sharply increase. The forces affect long, heavy trains more than shorter, lighter trains because long trains at any one time can have many sections moving over different grades and curves. When the combinations of grades and curves become numerous and they are encountered repetitively, as train No. 403 encountered between Pensacola and the Yellow River Bridge, the forces acting on and within the train become extremely variable and are dynamically incalculable. This may be the reason the computer simulations that attempted to duplicate the forces generated by train No. 403 did not develop compressive or lateral forces large enough to have caused a derailment. The ability of long, heavy trains to negotiate varying curves and grades has been examined within the industry's TTD program. Since maximum forces acting upon car couplers are affected by train tonnage, speed, and grades, the TTD program developed recommendations concerning these variables. For trains traveling 30 mph over 1 percent grades, the TTD program recommends a maximum of 8,000 trailing tons. This recommended tonnage is less than the 10,628 trailing tons estimated to have been on train No. 403 when it departed Pensacola and the 11,360 trailing tons actually on train No. 403 at the time of its derailment. The unusual impact markings on the striker casting and the broken coupler knuckle between the 36th and 37th cars were influenced by the 3,360 trailing tons on train No. 403 that were over the TTD-recommended maximum. On July 31, 1978, the Safety Board recommended that the FRA: Promulgate regulations to require railroads to limit the length and tonnage of trains carrying hazardous materials to train makeup principles developed under the track train dynamics program. (Class II, Priority Action) (R-78-46) The recommendation was made following the Safety Board's investigation of an accident at Pensacola on November 9, 1977. 9/ The FRA has not yet taken any action on this recommendation. Since L&N trains trains with large tonnage similar to train No. 403 have successfully negotiated the track through the derailment area, additional factors of train handling and train makeup may have contributed to train No. 403's 9/ "Railroad Accident Report--Louisville & Nashville Railroad Company Freight Train Derailment and Puncture of Anhydrous Ammonia Tank Cars, Pensacola, Florida, November 9, 1977" (NTSB-RAR-78-4). derailment. Critical factors affecting the train-handling aspects of train No. 403 were train speed, type of brake applications, and the speed needed to make the ascending Crestview grade. Additional train makeup factors were the 67 heavily loaded tank cars without baffles, the inadequate locomotive power, and the intermittent shutdown of the locomotive's fifth unit. The engineer's belief that the train was moving at 40 mph as it entered the descending grade to the Yellow River is probably accurate. The maximum allowable speed was 40 mph in the area, one locomotive unit had been shutting down intermittently, and the heavy tonnage of the train caused a lack of adequate locomotive power. With the recent FRA emergency order and increased surveillance on this line, the engineer probably would have been concerned about train overspeed even though the 30-mph FRA speed restriction had been removed. Also, because of the tonnage of the train and inadequate locomotive power, it is doubtful that the train, could have attained a speed much greater than 40 mph on the grades between Pensacola and Crestview. The engineer stated that he did not release the brakes after each application. However, the tests conducted by WABCO concluded that the train's speed down the grade and through the derailment area could have been kept at 35 to 40 mph only by releasing the brakes after each application. The L&N special rules governing train handling and the TTD program recommend a reduction in train speed before entering a descending grade. The engineer of train No. 403 said that he made a minimum service brake application after the train was already at the top of the grade. It is apparent that the engineer did not follow the recommended procedures when train No. 403 entered the grade at about the restricted speed of 40 mph. His failure to adequately slow the train before the grade necessitated the second minimum brake application and a full service brake application farther down the grade. When the engineer previously applied and released the brakes, he did not allow sufficient time between each application to restore necessary air pressure. This lack of air pressure led to the decrease in braking ability that was evident as the engineer made brake applications on the grade. This reduction in braking ability was confirmed in the brake tests conducted by WABCO. The WABCO tests also showed more braking on the lead cars of the train than on the rear cars. This condition allowed the rear of the train to continue moving momentarily faster than the lead portion when the engineer released the brakes as the locomotive left the 3° curve. The TTD program recommends against releasing the brakes when leaving curves of more than 2° in order to prevent heavy slack run-in and large lateral coupler forces. The continued slowing of the train from 35 to 30 mph after the brake release and movement through the 4°02' curve and up the grade to Crestview, even though the throttle was continually advanced, indicated an inability of the lead portion of the train to pull away from the rear portion which was still coming down the grade. Since eight L&N trains with similar tonnage had stalled and five others had experienced broken couplers or knuckles on the Crestview grade during the previous year, it is apparent that sufficient locomotive power to ascend the grade is critical. Train No. 403, with less than the recommended locomotive power, probably would not have been able to ascend the grade. Also, any lessening of wheel/rail adhesion because of wet rail due to the misting rain, and with the fifth |