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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.
4.2.8.1 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.
4.2.8.2 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.
4.2.8.3 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.
4.2.8.4 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.
4.2.8.5 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.
4.2.8.6 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%.
