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50 Hazardous Materials Transportation Incident Data for Root Cause Analysis 4.2.4 Data Compilation Reports filed by XML submission or online 5800.1 go directly into the database, which includes high-level quality control processing. For PDFs and faxes or paper forms delivered by package carriers, PHMSA scans and performs optical character recognition (OCR) for accuracy and then enters the record into the database. PHMSA also employs character-to-character checks to ensure that the OCR process translated the paper form properly. As part of the data entry process, PHMSA examines the form for personally identifiable information (PII), and such information is scrubbed from the report. For example, if the carrier name is the name of a per- son, the name is blanked out in the report. The HMIRS database is updated monthly. 4.2.5 Accuracy and Completeness of Data Aside from the inconsistencies that are discussed in Section 4.2.6, data accuracy is mostly con- trolled by the accuracy of the carrier reporting the information. The carrier has access to first- hand knowledge of the incident through personal interviews with the vehicle operator involved in the accident and repair information that documents the extent of the damage and the costs to complete the repairs. PHMSA staff, in interviews, complained that it is evident that many of the reports are reviewed by a lawyer prior to submission and they believe this review greatly weak- ens the value of the information reported. No individual or business wants to put information on the record that could be used against them in a civil suit. This is particularly true for the acci- dent reports that make up a small fraction of the HMIRS database. When questionable or incomplete information is provided, PHMSA staff contact the carrier and request additional information or clarification of the information they have received. In the case of injuries and fatalities, since HMIRS distinguishes among injuries and fatalities that are the direct result of exposure to the hazardous material and those as a result of the traffic acci- dent, all fatalities and injuries are validated by their own process to determine if they were caused by a hazardous material. This includes obtaining coroner reports and death certificates. Data compilers also look for any mention of injuries if none were marked on the form. In fiscal year 2009, PHMSA will introduce an online Incident Reporting System that will require filers to fix incorrect data before the submission will be accepted. However, since the car- riers will also be able to file the reports via the other methods available, the effectiveness of these checks will be limited to electronically submitted reports. Comparing HMIRS with TIFA to Evaluate Crash Data Accuracy As was the case for MCMIS, the TIFA file provides a unique opportunity to evaluate the accu- racy of the crash data reported by carriers to PHMSA and entered in the HMIRS database. Although the TIFA data is collected differently, the data associated with fatal truck crashes are checked rigorously for data quality. Consequently, TIFA data is highly reliable. In this discussion, and in subsequent comparative analyses of the accuracy of HMIRS data, it is important to recognize that not every attribute, including some cause codes, in the HMIRS database is considered. Rather, those that can be compared because similar information theo- retically exists in multiple databases are used to estimate the level of accuracy of the HMIRS data that are being collected. The TIFA file provides an opportunity to evaluate the completeness of reporting of a subset of hazmat incidents. The TIFA file includes all trucks that were involved in a traffic crash that included at least one fatality. Data collected includes whether the cargo on the truck was plac- arded as hazardous material and whether the cargo spilled. The TIFA file is based on NHTSA's FARS file, which is a comprehensive database of all fatal traffic crashes. UMTRI receives police

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Database Analysis 51 reports on all crashes involving a truck. Interviewers contact the truck owner, its operator, the carrier's safety director, the original reporting officer, or any other person knowledgeable about the truck at the time of the crash. The interviewers collect a set of detailed information about the configuration of the vehicle, which is cross-checked with multiple sources, such as manufac- turer's specifications. As such, the TIFA file should provide a complete record of hazmat releases in fatal truck crashes, incidents that should be in the HMIRS data. Given the seriousness of fatal truck crashes, one would expect these events to be among the most likely to be reported to HMIRS. Accordingly, estimates of reporting completeness in this subset may be regarded as close to the upper boundary of the plausible range for the true report- ing rate. TIFA and HMIRS data for 2005, the most recent year when both were available, were used in the comparison. The TIFA file includes all traffic accidents involving a medium or heavy truck and a fatality that occurred as a consequence of the accident, whether from hazmat release or not. Cases required to be reported to HMIRS involve either a release or damage to the lading system. The TIFA file records whether there was a hazmat spill, so HMIRS cases that meet that criterion can be iden- tified in TIFA. TIFA, however, does not capture information that indicates damage to the lading system, although it does capture rollover, which is probably strongly associated with damage to the lading system. Thus, the TIFA file should include all HMIRS-reportable cases that involve a fatal- ity and truck transportation. However, only the cases reportable because there was a hazmat release can be specifically identified in TIFA. Cases that are reportable because of damage to the lading sys- tem cannot be specifically identified, although many are very likely among those in which the truck rolled over. Of the 53 HMIRS highway cases in 2005, 50 were matched to a record in the TIFA file. The match had to be done manually; that is, by reviewing individual records, since there are no case identifiers in common between the two files. In addition, other potential match variables-- location and time--all had various problems. The time and even the date recorded in TIFA var- ied from the self-reported data in HMIRS. Time varied most frequently, often by +/-30 minutes. The only location information useful for the match that was common between the two files was the county name. In the TIFA file, county is captured as a numeric code (the Federal Informa- tion Processing Standards [FIPS] code, as found at html, which is part of a standard and widely used geographic identification system). In HMIRS, county is an alphabetic string, and therefore subject to the vagaries of spelling. There were vari- ations in spelling the county name and, in one case, an incident was reported as occurring in Albany County, NY, in the HMIRS data, but actually occurred in Albany County, WY. Hand- matching is unavoidable when such materials are all that is available. Three HMIRS cases did not appear in the TIFA file. This may occur if the vehicles transport- ing the hazardous material were not medium or heavy trucks. Each case was searched for in the 2005 FARS file. One case from Bronx, NY, was in FARS, but not TIFA. The vehicle was coded as a truck, so the case should have been included in TIFA. The reason it was not included is that it was added to FARS after the complete FARS file was released to the public. A corrected version of FARS was released with the case after the TIFA file was itself completed. It is likely that the two other records in HMIRS but not TIFA were inaccurately reported. One record was from Douglas County, KS, on 12/22/2005 at 6:30. This record seemed to be matched by three records in the 2005 FARS, which occurred on the same date at 6:38. But all three vehi- cles were light vehicles, and none coded in FARS as carrying hazmat cargo. However, it is known that FARS underreports hazardous material in cargo. Finally, a record from Lynchburg City, VA, on 1/31/2005, was not found in FARS at all. No fatal crash occurred in Virginia on that day. There may have been an error in the date of the incident in HMIRS, or some other error.

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52 Hazardous Materials Transportation Incident Data for Root Cause Analysis Table 4-13. TIFA hazmat crash involvements matched with HMIRS TIFA 2005/HMIRS 2005. Matched Cargo Spillage Total No Yes None 106 9 115 Spill of hazmat 27 40 67 Unknown 3 1 4 Total 136 50 186 Row Percentages None 92.2 7.8 100.0 Spill of hazmat 40.3 59.7 100.0 Unknown 75.0 25.0 100.0 Total 73.1 26.9 100.0 One criterion for reporting to the HMIRS file is a spill of hazardous materials. All fatal truck crash involvements in which hazmat cargo is released should be reported to the HMIRS. The TIFA data show that there were 67 trucks in a fatal crash in which hazardous material spilled (see Table 4-13). Forty of the records were found in HMIRS, for a reporting rate of 59.7%. Cargo spillage clearly is associated with reporting, as the data in the table show that only 9 of the 115 trucks with hazmat cargo that did not spill were reported. Overall, 26.9% of trucks carrying hazardous materials that were involved in a fatal crash were reported to HMIRS. Non-spill incidents, which nonetheless included damage to protection for the lading reten- tion system, are also required to be reported. This could account for the nine non-spill cases that were found in HMIRS and, likewise, the 106 non-spill cases that were not. The TIFA data do not include any information on whether there was damage to the system protecting the cargo reten- tion system of the truck, so there is no way to determine directly if such damage accounts for the observed pattern of reporting. However, the TIFA data include a variable that identifies whether the vehicle rolled over. Rollover should be strongly associated with damage to the truck, includ- ing the system protecting the cargo retention system, so trucks with hazardous material that rolled over as part of the crash would be expected to be reported to HMIRS. Again, there is no way to determine directly if they must be reported, but certainly a high proportion would be expected to qualify. In Table 4-14, the results of matching the HMIRS to the TIFA file are shown disaggregated by cargo spillage and whether the truck rolled over. In the top half of the table, match results are shown for trucks that did not have cargo spill in the crash. Of the cases that rolled over, and thus likely damaged the protection for the cargo retention system and qualified for reporting to HMIRS, only 4 of the 15 (26.7%) were actually reported to HMIRS. Only 5% of the 100 hazmat trucks in a fatal crash, with no spill and no rollover, were reported to HMIRS. Note, however, that trucks with a hazmat spill and rollover were reported at only a 61.2% rate. Crashes in which there was a spill, but no rollover, were reported at a 55.6% rate, somewhat lower but not practi- cally different. The TIFA file includes some limited information about the motor carrier, including whether the carrier was private, operating trucks incidental to another business, or for-hire, and whether the carrier operated in interstate or intrastate commerce.

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Database Analysis 53 Table 4-14. TIFA/HMIRS match results, by cargo spillage and rollover, TIFA 2005/HMIRS 2005. No Cargo Spill No spill Matched Rollover No Yes Total No roll 95 5 100 Rollover 11 4 15 Total 106 9 115 Row percentages No roll 95.0 5.0 100.0 Rollover 73.3 26.7 100.0 Total 92.2 7.8 100.0 Hazmat Spill Matched Rollover No Yes Total No roll 8 10 18 Rollover 19 30 49 Total 27 40 67 Row percentages No roll 44.4 55.6 100.0 Rollover 38.8 61.2 100.0 Total 40.3 59.7 100.0 Considering all records matched, there was little difference in reporting rates between private and for-hire carriers or between interstate or intrastate carriers. Fatal crash involvements of a truck carrying hazmat cargo operated by an intrastate carrier were reported 19.5% of the time, compared to 29.8% of involvements where the carrier was operating interstate. The rate for interstate carriers is somewhat higher, but there are too few cases for the difference to be consid- ered statistically significant. Rates for private and for-hire carriers are virtually identical, 26.5% and 28.3%, respectively. Although it is not possible to determine definitively whether each case qualified for report- ing either because of a spill or damage to the protection to the lading retention system, the results here at least bound the probable HMIRS reporting rate. On the high side is the 59.7% reporting rate observed for cases in which there was a hazmat release. All of these cases defini- tively qualified for reporting, yet less than three-fifths were actually reported. The lower bound for HMIRS reporting might be the overall reporting rate of 26.9% of fatal truck crash involve- ments with hazmat cargo. However, it is quite unlikely that the overall reporting rate is anywhere near as high as 59%. In the case of the MCMIS crash file, the overall reporting rate is about 75% of the reporting rate for fatal crashes. If the same ratio is applied to the HMIRS file, this would mean the overall reporting rate is about 45%. But the MCMIS crash file is reported by state agencies, and the FMCSA has an intensive program to increase reporting, including paying for changes to systems to increase reporting. The obligation to report to HMIRS falls on the thousands of private haz- mat carriers, and there is no systematic program to make sure that all appropriate cases are entered into the database. Thus, the overall reporting rate may be even lower than that of HMIRS. However, given current data, it is not possible to provide a more realistic estimate.