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54 Hazardous Materials Transportation Incident Data for Root Cause Analysis 4.2.6 Quality Control Process Reports that are not submitted electronically are checked twice. The first check ensures that the translation from the submitted form to the electronic record has been completed accurately. After the records have been placed in an electronic form, the records are checked for business rule inconsistencies, invalid dates, and invalid commodities (by cross-checking with the com- modities in the database). Additional checks include cases of city/county inconsistencies or when the report shows that 5.5 gallons were spilled from a 5-gallon container. In these instances, the filer is contacted and asked whether there were multiple packages that failed, following which, the information is corrected. An analysis of the data demonstrates that some obvious Q/A checks are not being performed. For example, several carriers that file thousands of reports each year file under more than a dozen names and several DOT numbers. The multiple DOT numbers are probably valid and are the result of acquisitions and mergers. However, since all hazmat carriers must annually register with PHMSA, the name of the carrier could be required to be selected from the Registration file. In cases where no entry of the DOT number is provided, the submission should be rejected and the carrier required to resubmit the report with the DOT number completed. Unfortunately, sev- eral large carriers that are submitting thousands of reports never provide a DOT number on a single report. 4.2.7 Interconnectivity with Other Databases The interconnectivity of HMIRS with other databases varies by mode. For trucks, the DOT number, date of incident, and county of incident provides a fairly good way to link records in HMIRS and MCMIS databases. Incident date, county, and the occurrence of a fatal accident might be a good technique to link HMIRS and TIFA. Although some effort was made, there seems to be no good way to link HMIRS and MISLE for ship or barge hazmat accidents. For cer- tain accidents, FRA and/or NTSB might select an accident for more study. In such cases, the addi- tional information that is collected may result in the identification of some contributing causes or even a root cause for the accident. 4.2.8 Analyses Using Database The HMIRS database underwent a major structural change that took effect at the start of 2005. The first part of this evaluation will look at the effect of the HMIRS structural change. This will be followed by an evaluation of some of the parameters that could identify contributing causes of hazmat accidents. Since HMIRS really focuses on package behavior, it is likely that any capa- bility for identifying contributing causes will be limited to package behavior. The final section will look at the gains that might be realized when HMIRS is coupled with other databases such as MCMIS, TIFA, RAIRS, and MISLE. 184.108.40.206 Effect of HMIRS Structural Changes Taking Effect in 2005 The major structural change made to HMIRS at the beginning of 2005 was to break up the three main tables, commonly labeled MAT, CON, and RMK into a series of smaller linked tables titled: IREPORT, IEVENT, IACTION, SHIPPER, MATERIAL, PACKAGE, PKGLAYER, and PKGFAIL. From an overall perspective, the material previously found in MAT is now found in IREPORT and SHIPPER. The material previously found in CON is now found in PACKAGE, PKGLAYER, and PKGFAIL. IEVENT appears to capture the descriptive text previously found in RMK, and IACTION is a new table that asks the carrier what actions have been taken to reduce the likelihood
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Database Analysis 55 or the consequences of this accident should the conditions that initiated the accident be present in the future. 220.127.116.11 Main Features of the Restructured HMIRS Database In the restructured database, the basic accident information is contained in the IREPORT Table. This table contains information regarding the date, time, and location of the incident, and the resulting consequences expressed in terms of hazmat- and non-hazmat-related fatalities and injuries, road closure durations, evacuations, and damage costs. The changes to IREPORT following the restructuring are described in Table 4-15. Similar tables could be prepared for the SHIPPER and PACKAGE Tables. In these cases, the data are restructured but there does not appear to be a significant expansion of the data fields. Overall, the restructured HMIRS provides a much-improved description of accident consequences. How- ever, there is limited information on the driver, description of the route, and conditions at the acci- dent scene. To obtain more accurate information on the accident scene, such as whether the acci- dent occurred on a curve or while turning at an intersection, one would have to be able to identify the location of the accident from the route and location fields and then refer to map software to determine the road geometry. The other alternatives would be to find the accident in MCMIS or access the specific PAR. Privacy concerns may limit the availability of some personal driver infor- mation. To make it publicly available, personal driver information could reside in a separate file that would be kept confidential. The packaging information provided before and after the restructuring of the database was extensive and has only improved. Capacity and quantity shipped is now requested as part of the report. 18.104.22.168 Relevant en Route Accident Statistics Table 4-16 shows the statistics for only those records with T_PHASE = 261, signifying the phase of operations is "en route" when ACCIDENT = T, signifying that the record is submitted because a reportable accident occurred. Tables 4-10 and 4-11 both summarized the records for the years 2005 and 2006, the first two years of reporting after the database reconstruction. Table 4-15. Main features incorporated into the restructured database. General Variables in Tables after Restructuring Status Prior to 2005 Topic Area IREPORT contains several fields that could be There were no fields that would Report used to relate incident reports to reports in other enable linking to records in other Referencing databases. databases. IREPORT contains numerous fields listing names, No information regarding person Contact addresses, and phone numbers of the person filling out the form recorded with Information filling out the report and provides entries to list the the accident record. police accident report number. Previously, only deaths and IREPORT breaks down the deaths and injuries Deaths and injuries from HM were listed and into public, employee, and emergency responders Injuries no breakdown into classes of for both HM and for non-HM. individuals was possible. Both the number and type of individuals evacuated is given, as is the duration of the evacuation. If a Previously, just the number of Evacuation major road was closed, the duration of the closure individuals evaluated was listed. is also given. Previously no listing of weather Conditions Weather condition is now listed. conditions was recorded. In addition to the transport phase, for air, Only the phase is given, en Phase additional information is given as to the step in the route, loading, unloading, or en multimodal operation where the spill occurred. route storage.
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56 Hazardous Materials Transportation Incident Data for Root Cause Analysis Table 4-16. Summary of IREPORT records for en route accidents. Totals Totals by RPT_TYPE Year Truck Rail by Year Report Type A 2005 274 48 322 A 2006 247 39 286 608 B 2005 0 0 0 B 2006 4 4 8 8 C 2005 20 0 20 C 2006 13 0 13 33 Totals 558 91 649 Table 4-12 provided an expansion of part of Table 4-11, focusing on en route accidents and the reason for reporting as determined by the RPT_TYPE parameter. Any accident that results in a hazmat spill is classified as "A," an undeclared hazmat spill is classified as a "B," and new report- ing category "C" indicates that a cargo tank with a capacity of 1,000 gallons or greater was involved in an accident in which (1) there was damage to the lading or the safety system protecting the lading such that repairs had to be made and (2) there was no spill of hazardous material. The totals in Table 4-16 are mostly from spills, as can be seen by comparing the rows for RPT_TYPE = A with the totals row in Table 4-16. Note, that all the air and vessel records are con- sidered spills and not due to an accident. Of the 7,306 reports in Table 4-10, Table 4-11 shows that only 649 are accidents. Note that the absence of air and vessel columns in Table 4-16 indi- cates that all the air and vessel records shown in Table 4-10 are spills not associated with any en route accident. The new requirement to report non-spills associated with cargo tanks having capacities of greater than 1,000 gallons if the ladling or the system protecting the ladling is damaged is shown under Report Type C. There are a total of 33 reported accidents that were coded under this new classification. The remainder of this analysis will look at these 649 reports. The first evaluation will focus on whether the 649 accidents associated with the IREPORT records have corresponding records in the SHIPPER, MATERIAL, PACKAGE, and PKGFAIL Tables. By successively linking the tables to the IREPORT records it is possible to determine if there are accidents in IREPORT that do not have corresponding records in the linked tables. When SHIPPER is linked, the total number of records increases from 649 to 730. However, none of the IREPORT records are dropped. This emphasizes that one of the features of the restructured data- base is its ability to separately provide an accurate description of the spills of hazardous materials and their behavior for those offered for transport by several shippers. The 558 truck accidents rep- resent material from 596 shippers while the 91 rail accidents were associated with 134 shippers. The only limitation found in the SHIPPER Table is that the destination field has been left blank for 105 SHIPPER records. From the standpoint of identifying contributing and root causes, the lack of destination information for a significant fraction of the records is probably not a limitation. When the MATERIAL Table is added, the number of records increases to 750 records, indi- cating that several accident records in IREPORT involve multiple types of hazardous material. Once again, all 649 accidents described in IREPORT are represented. Adding the PACKAGE Table increases the number of number of records to 762, indicating that some materials in mul- tiple packages have been described accurately. The number of accidents associated with these 762 packages remains 649, indicating that package information is available for all 649 accidents listed in IREPORT. When the PKGFAIL Table is linked to the other tables, the situation changes significantly. There are 130 accidents described in IREPORT that have no PKGFAIL
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Database Analysis 57 records and there are another 6 that have no failure cause for the package failure. Thus, the cause of package failure cannot be described for 78% of the accidents. A check was made to see if the package failure might be missing because these were Report Class C accidents (and thus no spill) but although 24 of the 33 Class C accidents are among the 136 with no PKGFAIL records, there are many where the information is missing. A query to look at the number of accidents with missing PKGFAIL records that were recorded as spills showed that all were flagged as spills. Clearly, the carrier should have provided a PKGFAIL record for all 130 of the accidents. 22.214.171.124 Significant Parameters HMIRS records request that the carrier reporting an accident fill out the PKGFAIL Table and from the WHY FAILED field, it is possible to identify why the package failed. Note that this is not why the accident occurred. A shipper could place some corrective actions in the IACTION Table that may be indicative of the contributing causes for the accident but the causes do not have to be listed in the database. HMIRS does not contain other driver infor- mation. Therefore, the only driver information in the database is that incidentally found in the IACTION Table. HMIRS also has very limited information on the location where the accident occurred. There are four relevant parameters that help identify the location of the accident: I_STATE, I_COUNTY, I_CITY, and I_ROUTE. The user guide requests that the I_ROUTE parameter specify the "street location on which incident occurred." Based on the 558 truck accidents that occurred in 2005 and 2006, the carriers filing interpret I_ROUTE to be a street address, a route designation, and fre- quently a mile marker or mile-post designation, or an intersection of two named or numbered highways. The I_ROUTE listings that were not considered adequate to identify the location of the accident provided were a blank entry, just the route designation, or an incomplete phrase that des- ignates the route location as some distance from an undefined point. Of the 558 truck accidents, the actual location of the accident could only be identified for 347 cases, just over 60% of the acci- dents. Thus, if route characteristics were a contributing cause of the accident, it would be impos- sible to identify those causes for 40% of the accidents reported in HMIRS. HMIRS also contains limited information on the vehicle characteristics. If the package type is a C, a cargo tank, and the volume shipped is larger than 5,000 gallons, one can infer that the vehicle configuration is a semitrailer hauling a cargo tank. If the vehicle configuration is a contributing cause for the accident, the HMIRS record must be coupled with data in MCMIS. In MCMIS, if the data fields are fully populated, the vehicle, driver, and road characteristics documented in MCMIS can be coupled with the package information in HMIRS to get a comprehensive picture of the driver, vehicle, package, and route characteristics present at the time of the accident. The restructured HMIRS database provides fields to enter the carrier's DOT number, a parameter not requested prior to the 2005 restructuring. If an accident meets the reporting cri- teria in both HMIRS and MCMIS, and the data fields are all filled out, then an analyst has a good description of the accident expressed in terms of driver, vehicle, package, and route characteris- tics. Coupling HMIRS with RAIRS and TIFA would provide a comprehensive picture of the acci- dent, just as is the case with coupling HMIRS with MCMIS. For a two-year period, there were no accidents involving hazardous materials that were reported on the water in both MISLE and HMIRS. The reporting criteria seem to be too different so for the few water spills of DOT-defined hazardous materials that occur as a result of ship or boat accidents, it is not possible to supple- ment the package data shown in HMIRS. For the DOT number field to be useful, it must be comparable with the corresponding field in MCMIS. HMIRS records the number as a number field and it is recorded in MCMIS as a text field. In MCMIS, sometimes there are letters like DOT and US preceding the number. If the let-
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58 Hazardous Materials Transportation Incident Data for Root Cause Analysis ters are ignored, it is easy to convert the text field into numbers and look for matches based on the date and state. The county and time can then be used to verify the matches. To begin with, the DOT number is not supplied for 60 of the 558 accidents, reducing the total number of pos- sible matches to 498. When the DOT number, date, and state of accident occurrence were used to match up the 498 accidents identified in HMIRS for years 2005 and 2006 with the much more extensive MCMIS file, a total of 110 matches were found. Four of the records were eliminated because the accident times were different by several hours and the counties were also different. Thus, for slightly more than 20% of the HMIRS records, the accident reporting criteria overlap suf- ficiently to require the accident to be reported in both databases. Of the 106 matched records, there were 8 records where the times were within 15 minutes but the counties were different. Using map- ping software, and the location field as a final determiner, it was concluded that in six of these eight differences, HMIRS recorded the wrong county and in the other two, the county reported in MCMIS was incorrect. In all of the cases, the accident location was very close to the county border, normally less than three miles. In the six cases where it is suspected that the county recorded in HMIRS is wrong, one possible cause is the extra step used in recording the county. Rather than entering the county name, the county FIPS code was used. Entering the actual name introduces the wide variety of misspellings possible. This impedes computer matches. The use of the FIPS code is much better. If the name was entered as a string, it could be used to cross-check with FIPS, which would be useful to guard against errors in entering the code. But the best approach may be to avoid having to use probabilistic matching and use a case identifier, such as police report number. Every time there is an extra step, an additional source of errors can arise. A single query was used to identify 110 accidents reported to both MCMIS and HMIRS that occurred for the same carrier on the same date, in the same state. These accidents were then screened to see if there were any cases where the MCMIS record should not have been joined with the HMIRS record. There were 12 records that were suspect and, in the end, 4 were believed to represent different accidents. One way to eliminate this 10% error rate would be to join additional fields. Requiring the county to be the same would have eliminated all 12 records, including the 8 where either HMIRS or MCMIS reported the wrong county. Time was more difficult to use because even for those believed to be reported in both data- bases, the times were often different by 15 minutes or more. Location was quickly rejected because of the vast difference in the types of information recorded for that field. Of the 106 MCMIS records that were joined to HMIRS, one-half were not flagged as being a hazmat shipment in any of the four hazmat descriptive fields in MCMIS. Thus, if the join between HMIRS and MCMIS had just looked at the MCMIS records that were flagged as being haz- mat, one-half of the incidents would have been missed. Information technology is rapidly advancing to the point that it is feasible to require the lon- gitude and latitude of the accident to be included as part of the accident record. Many states already have longitude/latitude as an entry on their police accident reports but few police offi- cers populate the field when filling out the form. It is not believed that the reason is their inabil- ity to know the coordinates of their position. Most police cars can be located geographically by their dispatcher and, for many companies, this capability also exists for trucks and trains. Thus, provided that a format for the longitude and latitude are specified--decimal degrees or degrees, minutes, and seconds--it should be possible to use these two fields to join records and thereby eliminate the screening step. Many handheld GPS devices will provide this information and, for those without a handheld device, the accident can be located on numerous free and commercial software packages. For these free packages, all that is needed is Internet access. 126.96.36.199 Class C Record Types In the restructured database, the 5800.1 form imposes a new requirement. If a cargo tank having a capacity of greater than 1,000 gallons is involved in an accident and the lading or the
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Database Analysis 59 system protecting the lading is damaged, the carrier is to report the accident even if there is no spill. The way these accidents are coded is to enter a "C" under the RPT_TYPE variable in the IREPORT Table. The other designations are "A" for a spill and "B" for an undeclared hazmat shipment. Of the 649 en route hazmat accidents, 33 shipments, all truck mode, were coded as RPT_TYPE = C for the years 2005 and 2006. The rate of carrier compliance with this new requirement to report some non-spill hazmat accidents for cargo tanks is difficult to determine. Would one expect more than 33 incidents in two years? Focusing just on the truck accidents, in 2005 and 2006, there are 558 records. A query for the cargo tank configuration shows that 442 of those accidents involved cargo tanks. One approach for investigating underreporting is to examine the rollovers reported as spills and determine if they are being over-represented. In the Hazardous Materials Serious Crash Analysis: Phase 2 (Battelle 2005) study, spills occurred in 66% of the rollovers. Of the 442 cargo tank accidents reported in HMIRS, 357 rolled over and of those rollovers, 291 were coded as spills. Thus spills occurred in 82% of all rollovers. Because rollovers are likely to damage the rollover protection system, spills from rollovers seem to be over represented in the HMIRS database. The number of cargo tank rollovers reported as Class C records was 23. The non- spill cargo tank rollovers would have to be increased from 23 in two years to 110, an increase of about 85 non-spill accidents to lower the spill rate to 66%. Is it reasonable that 110 cargo tanks would rollover in a two-year period and only 23 would experience damage to their rollover protection system that was serious enough to require repair? Given that cargo tank rollovers frequently result in a release, it might be anticipated that damage would occur in more than 21% (23/110) of the non-spill rollover accidents. Perhaps a more fundamental result is that if all cargo tank accidents that met the MCMIS definition of serious were required to be reported, the number of additional records being reported would increase by at most a few hundred. Given that there are more than 30,000 records added to HMIRS every two years, requiring all serious cargo tank accidents to be reported would increase the record load on PHMSA by less than 1%. By making the HMIRS reporting requirements have some of the same requirements as MCMIS, the added benefit is that more accidents would be reported in both databases. Since MCMIS has more information on the road configuration, environmen- tal parameters, and driver characteristics, it should be possible to perform more analyses that move toward identifying contributing and root causes of hazmat accidents. 188.8.131.52 Inclusion of IACTION Table One of the major changes in the restructuring of the HMIRS database was the addition of an action statement table that can be used by carriers to state the changes they propose to make to prevent or reduce the likelihood that such accidents would occur in the future. There are 649 accident records in IREPORT for 2005 and 2006 in which T_PHASE = 261 and ACCIDENT = T. These consisted of 558 and 91 truck and rail records, respectively. There are 453 records with action entries, 411 for truck and 42 for rail. Thus, the percentage of carriers providing action statements is 74% for truck and 46% for rail. In looking at the action statements, while the contributing cause is not given, it is clear that the contributing cause that resulted in the action statement is known by the carrier, but it just is not stated. Like the causes of failure that are used in the PKG_FAIL Table, a table of contributing causes could be developed and added to the IACTION Table that would provide the basis for the actions taken; they would not have to be assumed. The tables developed in the RAIRS might be a useful place to start when develop- ing this table of contributing causes. Even though no driver information is present in HMIRS, many of the actions focus on increased driver training, so it is clear that one of the contributing causes for many actions is inadequate driver training. Another goal would be to increase the number of carriers providing action statements, particularly for rail. A goal could be to have a compliance rate in excess of 90%.