New Hampshire Motor Vehicle I/M SIP Revision 

New Hampshire Departments of Safety and Environmental Services May 12, 2011 

The State of New Hampshire 

Motor Vehicle Inspection and Maintenance 

State Implementation Plan Revision 

Attachment VIII : 

Quality Assurance Programming Documentation 

Prepared by: 

The New Hampshire Department of Environmental Services 

Concord, NH 

November 1, 2011 

~ DEPARTMENT OF 

Environmental 

Services 

Attachment VIII : Quality Assurance Programming Documentation 1 
New Hampshire Motor Vehicle I/M SIP Revision 

New Hampshire Departments of Safety and Environmental Services May 12, 2011 

Quality Assurance Programming Documentation 

Table of Contents 

Quality Assurance Program Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3 

OBD Triggers Analysis Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3 

Attachment VIII : Quality Assurance Programming Documentation 2 
New Hampshire Motor Vehicle I/M SIP Revision 

New Hampshire Departments of Safety and Environmental Services May 12, 2011 

Quality Assurance Program Elements 

The elements of I/M quality assurance programs are outlined in 40 CFR 51 .363 and include : 

" Performance Audits, both overt and covert; 

" Record Audits; 

" Equipment Audits; and 

" Auditor Training and Proficiency 

This Attachment to the I/M SIP submittal describes a vehicle test data analysis protocol (triggers 

analysis) used in New Hampshire in lieu of covert performance audits . DOS has worked with their OBD 

II vendor to develop and use sophisticated electronic analysis "triggers" to evaluate the performance of 

the decentralized inspection stations and inspectors by identifying anomalies and irregularities that 

might indicate fraud . Trigger analysis results available to New Hampshire DOS, from the automated I/M 

data system, enable DOS staff to efficiently and effectively pursue follow-up investigations and 

enforcement actions against stations and inspectors whose results appear to be outside expected 

parameters. To provide additional insight into this process, the triggers analysis is summarized below. 

Triggers-based data analyses/reports are not canned summary versions that are produced by the I/M 

data system on a regular, periodic (e .g . monthly) basis. Instead, they are produced on an on-demand 

basis by DMV staff as needed to monitor inspections on an ongoing basis and to assist in investigations 

of specific stations or to search for particular patterns of potential violations or anomalies. 

New Hampshire will continue to evaluate incorporation of a covert auditing program in the state's I/M 

program in conjunction with the legislative OBD Advisory Committee . Should such a program be 

incorporated, DES will submit a SIP revision to reflect this change. At this time, however, it is the 

position of DMV and DES that the current triggers analysis is as, if not more, effective than a covert audit 

program utilizing vehicle set to fail . 

OBD Trigger Analysis Protocol 

The NHOST OBD Communication Protocol trigger compares the OBD test results from all the New 

Hampshire stations to those contained in a standard reference or "truth table" developed by the NHOST 

contractor, Gordon-Darby. Each OBD-equipped vehicle communicates with the NHOST test unit using 

one of five possible electronic OBD data exchange protocols. These protocols are standards established 

by the Society of Automotive Engineers (SAE) for use by all the vehicle manufacturers. Each vehicle's 

OBD communications protocol is programmed into it at the time of manufacture and cannot be 

changed, making it possible to compare OBD protocol data collected during an NHOST test to the 

protocol identified as originally installed in the vehicle . 

Gordon-Darbyl developed and maintains a "truth table" that contains proper OBD protocols for families 

of vehicles subject to testing in the NHOST program. The table was built using test records collected in 

New Hampshire along with data from Gordon-Darby"s other vehicle inspection programs in Arizona, 

Kentucky, and Texas. These test data are analyzed to determine the reference communications protocol 

for each type of vehicle . 

1 Gordon-Darby is recognized as an I/M Program industry expert in data collection and analysis . Gordon-Darby, 

with Sierra Research, developed a comprehensive triggers best practices guidance document for the United States 

Environmental Protection Agency (EPA) : "QA/QC Procedures Based on Program Data and Statistical Process 

Control Methods for I/M Programs," prepared for EPA, Certification and Compliance Division ; Sierra Research, Inc., 

Report No. SR01-10-02, October 2001. 

Attachment VIII : Quality Assurance Programming Documentation 3 
New Hampshire Motor Vehicle I/M SIP Revision 

New Hampshire Departments of Safety and Environmental Services May 12, 2011 

The NHOST OBD Communication Protocol trigger returns results showing the count and percent of tests 

performed by each station which have recorded protocols that (1) match those contained for each 

applicable VIN in the truth table, (2) do not match, and (3) are unknown. The last "unknown" group are 

the ones for which the truth table does not contain an identified protocol for that particular VIN . A test 

in which the recorded protocol does not match the type contained in the truth table is strong evidence 

that a vehicle other than the one that is supposed to be tested was fraudulently used in performing the 

OBD test. This type of fraud is known as clean scanning, in which a vehicle that passes the OBD test is 

tested in place of the vehicle actually subject to OBD inspection. Stations that have recorded a high 

count or high proportion of such protocol mismatches are likely involved in significant test fraud and are 

more closely scrutinized for enforcement action. 

In addition, there are two consumer hotlines available to report potential inspection station fraud . The 

DOS-DIVIV maintained consumer inquiry line is (603) 271-8800. Gordon-Darby maintains the consumer 

inquiry line (800) 295-5276. Both of these phone lines are printed on each vehicle inspection report. 

Attachment VIII : Quality Assurance Programming Documentation 4