### Envirotest Systems 5175 Marshall St., Arvada, Colorado 80002



# The Colorado Remote Sensing Program January – December 2013

September 2014

Prepared for: 

# The Colorado Department of Public Health and Environment

Prepared by:

Peter M McClintock, Ph.D. Applied Analysis 13700 Marina Pointe Drive #301 Marina Del Rey CA 90292-9276 pm2pt5@gmail.com

### 2 

## Acknowledgments

The author wishes to acknowledge the support a nd input given by a number of individuals and organizations. Particular thanks are extended to the follo wing contributors: CDPHE for providing many helpfu l comments and suggestions. Drew Rau, Envirotest Program Operations Division and the Remote Sensing unit of Envirotest, Tucson for providing data access and operational information.

### 3 

## Table of Contents

I. SUMMARY ....................................................................................................................... ............................. 5
II. DESCRIPTION OF THE DENVER CLEAN SCREENING PROGRAM ........................................... 8

A. I/M P ROGRAM 

### O VERVIEW 

### ........................................................................................................................ 8 B. M EASUREMENT 

### S ITES



### ............................................................................................................................. 13 C. S OURCES OF 

### D ATA AND 

### D ESCRIPTION OF 

### E LEMENTS 

### ............................................................................. 18
III. SUMMARY OF DATA COLLECTION ................................................................................................ 21

A. M ONTHLY 

### C OLLECTION 

### A CTIVITY 

### ......................................................................................................... 21 B. M EASUREMENTS BY 

### H OUR OF 

### D AY 

### ........................................................................................................ 21 C. C OMPOSITION OF 

### V EHICLES 

### M EASURED 

### ................................................................................................. 23
IV. CLEAN SCREENING PROGRAM PERFORMANCE ....................................................................... 25

A. V EHICLES 

### S ELECTED 

### , N OTICES AND 

### R EDEMPTIONS 

### ............................................................................... 25 B. C LEAN 

### S CREEN 

### P ROGRAM 

### E FFECTIVENESS 

### ............................................................................................ 27 C. G AS 

### C AP 

### E VAPORATIVE 

### E MISSIONS 

### ....................................................................................................... 30 D. H YBRID 

### RSD-LEI VS



### . 2- HIT 

### RSD ........................................................................................................... 33
V. ESTIMATE OF OVERALL I/M PROGRAM BENEFITS AND CLEAN SCREEN IMPACT ....... 36
A. C ONVERSION OF 

### I DLE 

### T ESTS TO 

### IM240 E QUIVALENT EMISSIONS 

### ........................................................... 36 B. A NNUAL 

### M ILEAGE 

### W EIGHTING 

### .............................................................................................................. 40 C. A NNUAL 

### E MISSIONS 

### R EDUCTIONS 

### .......................................................................................................... 41
VI. IM240 PROJECTED EMISSIONS BY MODEL YEAR ..................................................................... 43
VII. RAPIDSCREEN BENEFITS .......................................................................................................... ........ 47
A. G REENHOUSE 

### G AS AND 

### P OLLUTANTS FROM 

### C LEAN 

### S CREEN 

### O PERATIONS 

### ............................................ 47 1. RapidScreen Opera ting Vehicles ................................................................................................ ........... 47 2. Generators .................................................................................................................... ......................... 48 3. Calibration and Audit Gases ................................................................................................... ............... 48 4. RapidScreen Vehicle Em issions Redu ctions ...................................................................................... .... 48 B. R APID 

### S CREEN 

### V EHICLE 

### O WNER 

### S AVINGS 

### .............................................................................................. 49
VIII. RECOMMENDATIONS ............................................................................................................... ...... 50

REFERENCES

APPENDICES

A1 COLORADO 2012 TRANSIENT TEST EMISSIONS REDUCTIONS A2 COLORADO 2012 CLEAN SCREEN AUDI T TRANSIENT TEST EMISSION REDUCTIONS B COLORADO 2012 TRANSIENT TEST REDUCTION TONS

### 4 

## List of Tables

T ABLE 

### II-1 N ORTHERN 

### F RONT 

### R ANGE 

### ................................................................................................................... 14 T ABLE 

### II-2 D ENVER 

### RSD S ITES 

### ............................................................................................................................. 1 5 T ABLE 

### II-2 D ENVER 

### RSD S ITES CONTINUED 

### ......................................................................................................... 16 T ABLE 

### II-3 E L 

### P ASO 

### RSD S ITES



### ............................................................................................................................. 16 T ABLE 

### II-4 V EHICLE 

### M EASUREMENT 

### I NFORMATION 

### ............................................................................................. 19 T ABLE 

### III-1 C OLLECTION 

### S UMMARY 

### ...................................................................................................................... 21 T ABLE 

### III-2 S OURCE OF 

### V EHICLE 

### R EGISTRATIONS 

### M EASURED BY 

### RSD .............................................................. 23 T ABLE 

### III-3 T YPE OF 

### V EHICLES 

### M EASURED BY 

### RSD WITHIN 

### R EGISTRATION 

### J URISDICTION 

### ................................ 24 T ABLE 

### III-4 R EGISTERED 

### J URISDICTION AND 

### A GE OF 

### V EHICLES 

### M EASURED BY 

### RSD ........................................... 24 T ABLE 

### IV-1 V EHICLES 

### Q UALIFIED 

### A S 

### M EETING 

### C LEAN 

### S CREENING 

### C RITERIA BY 

### S TATUS 

### ................................... 25 T ABLE 

### IV-2 N OTIFICATIONS 

### T RANSMITTED TO 

### DOR ............................................................................................. 26 T ABLE 

### IV-3 C LEAN 

### S CREEN 

### A UDIT 

### T EST 

### P ASS 

### / F AIL 

### S TATISTICS 

### ........................................................................ 26 T ABLE 

### IV-4 T RANSIENT 

### T EST 

### E MISSION 

### R EDUCTIONS FOR 

### 1982-1985 P ASSENGER 

### V EHICLES 

### ............................. 29 T ABLE 

### IV-5 C LEAN 

### S CREEN 

### E MISSIONS 

### I MPACT FOR 

### T AILPIPE 

### E MISSIONS 

### ........................................................... 30 T ABLE 

### IV-6 C LEAN 

### S CREEN 

### I MPACT ON 

### E VAPORATIVE 

### HC E MISSIONS 

### ................................................................ 32 T ABLE 

### IV-7 G AS 

### C AP 

### R ELATED 

### B ENEFIT 

### T ONS 

### ..................................................................................................... 32 T ABLE 

### IV-8 A VERAGE 

### E MISSIONS PER 

### V EHICLE 

### ................................................................................................... 34 T ABLE 

### V-1 L OW 

### S PEED 

### I DLE TO 

### IM240 ................................................................................................................. 37 T ABLE 

### V-2 H IGH 

### S PEED 

### I DLE TO 

### IM240 ................................................................................................................ 38 T ABLE 

### V-3 E STIMATED 

### A NNUAL 

### M ILEAGE IN 

### 2013 ............................................................................................... 40 T ABLE 

### V-4 E STIMATED 

### A NNUAL 

### T ONS OF 

### R EDUCTION 

### (IM240 AND 

### I DLE 

### T ESTED 

### V EHICLES 

### ............................... 42 T ABLE 

### VII-1 R EDUCTIONS IN 

### G REENHOUSE 

### G ASES AND 

### P OLLUTANTS FROM 

### R APID 

### S CREEN 

### O PERATIONS 

### ............ 47



## List of Figures

F IGURE 

### I-1 A VERAGE 

### IM240 E MISSIONS 

### R EDUCTIONS 

### ............................................................................................ 7 F IGURE 

### II-1: T AG 

### E DIT TM 

### S CREEN 

### ........................................................................................................................... 12 F IGURE 

### II-2 A 

### : S ITE 

### L OCATIONS 

### N ORTHERN 

### F RONT 

### R ANGE 

### ................................................................................... 17 F IGURE 

### II-2 B 

### : S ITE 

### L OCATIONS



### – D ENVER 

### M ETRO 

### A REA 

### ...................................................................................... 18 F IGURE 

### III-1 M ONTHLY 

### RSD M EASUREMENTS 

### ...................................................................................................... 22 F IGURE 

### III-2 M EASUREMENTS BY 

### T IME OF 

### D AY 

### .................................................................................................... 22 F IGURE 

### IV-1 G AS 

### C AP 

### P RESSURE 

### F AILURE 

### R ATES 

### ................................................................................................ 31 F IGURE 

### IV-2 A VERAGE 

### I NITIAL 

### IM240 E MISSIONS 

### ................................................................................................ 34 F IGURE 

### IV-3 A VERAGE 

### IM240 E MISSIONS 

### R EDUCTIONS 

### ....................................................................................... 35 F IGURE 

### V-1 RSD VS



### . I DLE 

### T EST 

### E MISSIONS 

### .......................................................................................................... 37 F IGURE 

### V-2 RSD VS



### . 2500 I DLE 

### T EST 

### E MISSIONS 

### ................................................................................................. 38 F IGURE 

### V-3 RSD VS



### . IM240 T EST 

### E MISSIONS 

### ....................................................................................................... 39 F IGURE 

### VI-1 LDGV HC R EDUCTIONS AND 

### R EMAINING 

### E MISSIONS 

### ...................................................................... 44 F IGURE 

### VI-2 LDGT HC R EDUCTIONS AND 

### R EMAINING 

### E MISSIONS 

### ...................................................................... 44 F IGURE 

### VI-3 LDGV CO R EDUCTIONS AND 

### R EMAINING 

### E MISSIONS 

### ...................................................................... 45 F IGURE 

### VI-4 LDGT CO R EDUCTIONS AND 

### R EMAINING 

### E MISSIONS 

### ...................................................................... 45 F IGURE 

### VI-5 LDGV NO X 

### R EDUCTIONS AND 

### R EMAINING 

### E MISSIONS 

### ................................................................... 46 F IGURE 

### VI-6 LDGT NO X 

### R EDUCTIONS AND 

### R EMAINING 

### E MISSIONS 

### ................................................................... 46

### 5 

## I. Summary
The Colorado Department of Public Health & Environment (CDPHE) and the Department of Revenue (DOR) have operated an Enhanced Inspection and Maintenance (I/M) program in the Denver metropolitan area (DMA) since 1995. Operations for a remote sensing clean screening element commenced in 2003. Previ ous reports, “The Colorado Clean Screening Program’ reports for July 2003 – December 2004 and annual reports for 2005-2012 1 

### described on-road measurement activities and the vehicles exempted from inspection. This report covers calendar year 2013. The clean screening program uses remote se nsing to measure the tailpipe emissions of vehicles as they drive by measuring equipment positioned on the side of the road. Vehicles that are determined to have low tailpipe emi ssions are granted an exemption from the I/M inspection. Clean screening improves convenien ce of the I/M program for vehicle owners. In order to exempt vehicles from inspection, computer systems and procedures are required for administering the program and notifying vehi cle owners of their in spection exemption. The I/M program is registration enforced a nd the administration of the clean screening program requires the transmission of inform ation among the contractor, CDPHE and DOR who manage motor vehicle registrations. Rapidscreen provided benefits to vehicle owners of $5.1M th rough reduced time and expense associated with eliminated insp ection station visits. The reduction in station inspections also yielded net savings in greenhouse gases and over 195,000 gallons of gasoline. Collection Activity In 2013, eighteen RSD vans were deployed in the DMA with an additional 4 in the Northern Front Range (NFR). Twenty-four different RS D systems were used as some units were rotated for preventive or co rrective maintenance and four RSD 5000s were used. Van’s deployed at 63 locations in the DMA, 28 sites in the NFR and 2 sites in Colorado Springs for a total of 23,038 active collection hours. A to tal 7.1 million emission measurements were collected and successfully matched to Colorado registered vehicles . Additional remote sensing productivity information is provided in Section IV. Expanded vehicle emissions testing began in part s of Weld and Larimer counties in late 2010. Vehicle owners with December 2010 renewal date s were the first required to get a test. 2012 vs 2013 Collection Comparison In 2012, RSD performed over 6.7 million emission measurements at 80 locations in the DMA and 35 locations in the NFR. In 2013 there were 0.3 million more emission measurements. Despite the increase in the quantity of emi ssion measurements the number of clean screens issued were 6% lower, being 280,310 in 2012 vs. 263,431 in 2013.

### 6 

### Vehicle Exemptions Almost 274,000 vehicles measured on-road initi ally met the clean screening exemption criteria. Two percent of these were reserved to provide a program audit sample and others were eliminated during the QA reviews, for exam ple, as a result of vehicle plate changes. The owners of the remaining 263,431 vehicles meeting the clean screening cr iteria were issued notices granting exemption from the I/M test at an inspection statio n. Of these vehicles, 233,760 (88.7%) owners took advantage of the Clean Screen exemption. Two methods were used to qualify vehicles, 2-RSD and Hybrid. With the 2-RSD method, vehicles qualified for an exemp tion if they had two or more on-road measurements and the most recent two measurements both showed emi ssions within the clean screen standards. With the ‘Hybrid’ clean screening method ve hicles measured once by remote sensing qualified for clean screening if the emissions measurement was within the clean screen standards and the vehicle model had a histor ically low rate of emissions problems. A 2% random sample of vehicles that qualifie d was not issued exemption notices and 4,460 of these vehicles were subsequently inspected at an enhanced inspection station. The results of the station inspections were used to evaluate the effectiveness of the program. Additional information about vehicles mailed notices is provided in Section IV. Clean Screen Program Effectiveness In a Clean Screen program, some vehicles pass ing the clean screen emissions criteria might have failed if inspected at an inspection sta tion. Therefore, a Clea n Screen program, while greatly improving convenience for vehicle owners, can slightly reduce the overall effectiveness of the I/M program. On May 5 th 

### 2008, IM240 Denver Metro Area station test standards were tightened – especially for HC and NOx – to bring them into closer alignment with EPA final standards. The LEI table was updated with subsequent IM240 results to reflect consequent changes in inspection result statis tics for vehicle models in Decembe r 2008, and annually thereafter. The RSD standards were updated in October 2010 w ith the addition of an RSD NO standard of 1000ppm that first applied to December 2010 registrants. Figure I-1 compares the average IM240 exhaust reductions per vehicl e inspected at stations to those of the 2-RSD audit sample and the Hybr id RSD-LEI audit sample. For HC and CO pollutants the RSD-LEI audit sample showed sm aller reductions than 2-RSD while the 2-RSD method performed better for NOx. For 2013, based on the 2% random audit vehicles tested with IM240, it was projected that 97.3%, 96.7% and 97.6% of HC, CO and NOx of program exhaust emission reductions were retained. The impact on gas cap related evaporative emissions was projected to be another 2.5% of HC reductions.

### 7 

### Figure I-1 Average IM240 Emissions Reductions

The methodology for estimating clean screen effec tiveness only allows for a score of 100% or less and uses the IM240 test as a “gold’ standa rd. Any variations in vehicle performance or the IM240 test procedure that produce an anomal ous IM240 test failure are scored against Clean Screen. Therefore, it is possible the Clean Screen effectiveness was better than projected. The recommendations section of the report suggests flexibility be added to Regulation 11 to prepare for program changes being implemented in 2015 and their effects on the remote sensing program. 0.00 0.02 0.04 0.06 0.08Station2-RSDRSD-LEIg/mi HC

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9Station2-RSDRSD-LEI 

### CO

0.00 0.02 0.04 0.06 0.08 0.10Station2-RSDRSD-LEI 

### NOx

### 8 

## II. Description of the Denver Clean Screening Program A. I/M Program Overview The Colorado Department of Public Health & Environment (CDPHE) operates an enhanced Inspection and Maintenance (I/M) program in the Denver metropolitan area (DMA) and the Northern Front Range (NFR). The clean screen ing component of the IM program uses remote sensing equipment to measure the tailpipe em issions of vehicles as they drive by the measuring equipment. Vehicles that are determin ed to have low tailpipe emissions are granted an exemption from their I/M inspection. Operating rules for the Clean Screening progra m are contained in the Air Quality Control Commission’s Regulation 11 2 

### . The Regulation defines the ma ximum percentages of vehicles that may be evaluated by the clean screen pr ogram in the enhanced I/M area. In 2006, the percentage of vehicles allowed to be evalua ted using remote sensi ng was decreased from 80% to 50% as part of an Early Action Compact (EAC) to achieve an earlier attainment designation for ozone. Clean Screening regulations were expanded in 2007 to allow use of a single RSD measurement combined with an index of lo w emitting vehicles to evaluate exemption candidates. The Low Emitter Index (LEI) was developed using I/M240 data to identify vehicle groups that historically have a ve ry low probability of failing. The current requirement for a vehicle group to qualify as a low emitter is they must have an I/M240 pass rate of 98% or greater. There are multiple requirements and restrictions fo r vehicles to participate in the Clean Screen program as defined in Regulation 11. The followi ng are the primary elements for vehicles to qualify for a clean screen exemption.

 The applicable observations were within twelve months prio r to the individual vehicles registration renewal date,

 The two most recent observation re sults are below, 200ppm, 0.5%, and 1000ppm for HC, CO, and NOx respectiv ely, (NOx standard implemented October 2010)

 The two most recent observations must have occurred on a different day or on the same day at different site locations,

Contractor 

### Envirotest was contracted to operate the e nhanced program by a competitive bid process and the contract was subsequently amended to include clean screening in the Denver area. Envirotest uses technology derived from that or iginally developed at Denver University with whom Envirotest has a royalty agreement.

Theory of operation The RSD is a system designed for a non-intrus ive measurement of vehicle emissions. It generates and monitors a non-dispersive infrared and dispersive ultra-violet beam emitted and

### 9 

### reflected approximately 10 to 18 inches above ground preferably across a single lane road. Gasoline, diesel, or other fossil fuel powered ve hicles drive through this beam and the exhaust interferes with this transmission of the be am. Quantifying the interference enables the calculation of tailpipe concentrations of CO, HC, CO2, NO and particulate matter. A camera simultaneously captures a digitized video image of the rear of the vehicle and its license plate. Equipment The equipment initially deployed in the No rthern Front Range counties were RSD-3000 mobile units also called AccuScan TM 

### . Successor RSD 4000 units were introduced in 2003. Both systems were based on a technical platform developed at the University of Denver by Dr. Donald Stedman. In 2007, additional RSD4600 units were added. The RSD4600 is very similar to the RSD4000-L3 system describe d below. The RSD4600 has a more compact speed and acceleration measurement bar and mo re diagnostic ports. Functionally, the two systems are the same. One RSD 5000, the la test generation of RSD systems, passed acceptance testing in 2011 and began data co llection in December 2011. The RSD 5000 is more compact, requires less power a nd supports remote wireless operation. AccuScan measures the exhaust of a passing motor vehicle in less than 0.7 seconds. Nondispersive infrared (IR) spectroscopy, the same an alytical technique used in garage based twospeed idle and ASM equipment is used to measure concentrations of CO, HC, and CO 2 

### . Dispersive ultraviolet (UV) spectroscopy is used to measure NOx. The system is based on the original designs and patents of Dr. Donald St edman, professor emeritus at the University of Denver. The following elements comprise a complete RSD4600 unit:

 RSD 4-gas analyzer Source Detector Module

 Corner Cubed Mirror Module (CCM)

 Two Alignment stands, one each for SDM and CCM

 Speed/Acceleration subsystem consisting of:

 Two Speed/Acceleration bars: one em itter and one detector bar with adjunct hardware

 Speed/Acceleration computer

 Digital Video camera and speed subsystem

 Computer control console subsystem consisting of:

 Video monitor

 Pentium TM 

### –based PC

 Additional PC cards and inte rnal hardware PC cards:

 Hard drive

 Removable Mass Storage

 Matrox video

 Serial and COM port

 RSD operation (data collection) software

 RSD compatible license plate tag-editing software

### 10 

###  Calibration and auditing s ubsystem consisting of:

 Calibration gas cell

 Audit tube

 Audit gas bottle

 Pressure regulator

 Hoses with quick disconnects

 RSD shipping container for SDM and CCM



### The following elements comprise an AccuScan TM 

### van:

 Ford one-ton truck

 Triton V-8 engine with 4-speed automatic transmission

 12 – 14 foot box on bed of truck

 Roof-mounted 13,500 BTU Coleman air-conditioner

 5 kW Onan generator

 Connector panel for quick connection of external cables and calibration gas hoses

The RSD unit takes multiple rapid readings for each vehicle to characterize the exhaust plume profile and evaluate whether a valid measurement of a vehicle’ s exhaust has been achieved. The criteria include how much vehicle exhaus t plume is available for the duration of the sampling period, evaluation of whether plume measurements are consistent with normal plume dissipation, and correction for changes in background concentrations of emissions. The RSD units comply with the CDPHE, “C olorado On-road Vehicle Emissions Remote Sensing System (COVERS) Specifications” Amended July 2010 3 

### : The COVERS accuracy specifications are consistent with the California BAR OREMS Specification: 1 

### and include: Detector accuracy:
1. The CO 2 

### % reading shall be within  10% of the Certified Gas Sample, or an absolute value of  0.25, or shall be within published manufacturer’s specification – whichever is less restrictive. Negative values shall be included and shall not be rounded to zero.

2. The CO% reading shall be within  15% of the Certified Gas Sample, or an absolute value of  0.25 (whichever is greater). Negative values shall be included and shall not be rounded to zero.

3. The HC reading (ppm pr opane) shall be within  15% of the Certified Gas Sample, or an absolute value of  250ppm (whichever is greater) . Negative values shall be

1 On Road Emissions Measurement System OREMS) Specifications, Revision L, Bureau of Automotive Repair, Engineering

and Technical Research Branch, 10240 Sy stems Parkway, Sacramento, CA 9582 7; 2001 California DCA/BAR; p. 5.

### 11 

### included and shall not be rounded to zero.

4. The NOx reading (ppm) shall be within  15% of the Certified Gas Sample, or an absolute value of  250 ppm (whichever is greater). Negative values sh all be included and shall not be rounded to zero.

5. COVERS shall submit readings within the following limits: CO + CO 2 

###  21.0 %, HC  35,000 ppm hexane, CO 2 

###  16.0 %, and NO  7000 ppm.

6. The system shall record at least three a nd display at least two measures of plume characteristics, for example the maximum nu mber of CO2 molecules seen, the average number of CO2 molecules seen, and the number of valid samples (measurements) made.

7. Each unit shall demonstrate during contro lled acceptance testing the above criteria 98% of the time. Ninety-eight percent (98%) shall mean that one hundred percent (100%) of the valid records shall have th e following fields fill ed correctly with accurate data, ninety-eight pe rcent (98%) of the time: CO2% CO % HC ppm hexane NO ppm Speed and Acceleration Accuracy:
1. The vehicle speed measurement shoul d be accurately recorded within  1.0 mile per hour.

2. The vehicle acceleration measurement shoul d be accurately recorded within  0.5 mile per hour / second.

3. The speed and acceleration system shall demonstrate during controlled acceptance testing the above criteria ni nety-five percent 95% of the time. Ninety-five percent (95%) shall mean that one hundred percent (100%) of the valid records shall have the speed and acceleration fields filled co rrectly with accurate data, ninety-five percent (95%) of the time.

4. VSP shall be calculated during host pro cessing using the most recent CDPHE approved equation.

Vehicle Identification The system captures emissions readings and rear pictures of vehicles passing through the RSD infrared beam. The video and emissions readin gs taken are stored directly on a removable media disk and can be used for future reference.

### 12 

### Envirotest’s TagEdit TM 

### software is used to transcribe vehicle license plate information. Figure II-1 below shows an example of a TagEdit TM 

### screen. This license plate editing service is superior to an automatic license plate reader because:

 All video images associated with valid emi ssions data get processed. This ensures the highest possible vehicle capture rate.

 Vehicles with special plates are also processed . This is especially important in areas where many unique license plates are issued. Fa ilure to process all plate types can create a statistically skewed database that could be misinterpreted by the public as “targeting” only certain vehicle classes. 

### A special registration database was created for th e Clean Screen program to allow vehicles to be identified (VINs) from Clean Screen lice nse photos captured days prior to their data processing. This Clean Screen registration database is updated nightly with all the changes statewide that affect what VIN is associated with what plate. A lag time interval is incorporated to allow time fo r updates to get from the Count y Clerks Offices to the DOR database. The separate Clean Screen Registrati on Database on the Envirotest host contains all vehicle registration records statewide, even though only certain counties are expected to participate in the Clean Screen program. The fu ture growth of registration could require some housekeeping, but there is plenty of hardwa re scalability to handle this growth.

Figure II-1: TagEdit TM 

### Screen

### 13 

### B. Measurement Sites Good remote sensing sites are critical for obtai ning RSD measurements that are representative of vehicle operation. Recomm ended site attributes include:
(1) Absence of cold start vehicle operating conditions
(2) Sites where vehicles will generally be accelerating or driving at a steady speed uphill to ensure adequate engine power and exhaust plumes and avoid the problem of RSD not measuring vehicles that have vi rtually no exhaust under deceleration
(3) Absence of enrichment due to high load conditions
(4) Single lane operation
(5) High volume traffic
(6) Unobtrusive siting of the remote sensing equipment
(7) Adequate median space for safe operation of the RSD equipment.



### Table II-1 lists the RSD sites in the Northern Front Range (NFR), the number of days each site was used, the total hours dur ing which measurements were collected and the number of vehicles measured per hour. The hours shown do not include travel time to and from the site, equipment set-up and equipment takedown time.
Table II-2 lists the Denver Me tro Area (DMA) site locations. Table II-3 lists the El Paso County (Colora do Springs) locations where a small number of measurements are made annually. Site locations in the NFR and DMA are illustrated in Figures II-2a and IIb. Blue sites are active. Red sites are no longer permitted. The X's represent HQ and other stations where RSD vans are housed.

### 14 Table II-1 Northern Front Range

Site Code Location City Active Days Total Active Hours Registered Vehicles Measured Veh's Per Hour 2144 NB STANDFORD FROM MONROE DR FT COLLINS 2 10 802 78 3019 ON RAMP TO NB I-25 FROM 402 (CR-54) LOVELAND 16 68 6,703 99 3020 ON RAMP TO SB I-25 FROM 402 (CR-54) LOVELAND 20 109 12,974 119 3510 SB SHIELDS ST. AFTER FOSSIL CREEK FT. COLLINS 3 18 3,613 200 3511 OFF-RAMP FROM NB I-25 TO WB MULBERRY ST. FT. COLLINS 28 209 59,474 285 3513 NB SHIELDS RD. AFTER BON HOMME RD. FT. COLLINS 4 23 1,122 50 3514 NB TAFT HILL RD. AFTER HARMONY RD. FT. COLLINS 77 521 196,148 377 3515 ONRAMP TO NB I-25 FROM WB US-34 FT. COLLINS 32 236 34,364 146 3517 ONRAMP TO SB I-25 FROM CROSSROADS BLVD. FT. COLLINS 4 29 2,963 102 3527 EB 392 AFTER INTERSECTION WITH CR-9 FT. COLLINS 19 149 23,993 161 8042 ONRAMP TO SB I-25 FROM EAST PROSPECT FT COLLINS 71 521 123,542 237 8049 ONRAMP TO SB I-25 FROM HARMONY RD FT COLLINS 23 160 42,080 264 8053 EB US-287 ABOUT 500' EAST OF LCR-17 BERTHOUD 14 80 3,205 40 2989 EB US 34 BYPASS FROM 23RD AVE GREELEY 43 314 46,298 147 3506 ONRAMP TO NB US-85 FROM HWY 52 FT. LUPTON 2 12 558 48 3507 ONRAMP TO SB US-85 FROM HWY 52 FT. LUPTON 10 58 8,730 151 3518 ONRAMP TO SB I-25 FROM SR-60 LOVELAND 4 27 2,180 81 3519 ONRAMP TO SB I-25 FROM SR-56 BERTHOUD 5 21 866 41 3520 ONRAMP TO SB I-25 FROM SR-66 LONGMONT 1 5 542 118 3521 ONRAMP TO SB I-25 FROM SR-52 LONGMONT 44 256 63,414 247 3522 ONRAMP TO SB I-25 FROM CR-8 DACONO 10 49 3,692 75 3523 ONRAMP TO NB I-25 FROM CR-8 DACONO 1 4 31 7 3524 ONRAMP TO NB I-25 FROM SR-52 LONGMONT 2 9 845 94 3525 ONRAMP TO NB I-25 FROM SR-119 LONGMONT 11 49 6,455 133 3526 ONRAMP TO NB I-25 FROM SR-66 LONGMONT 5 28 2,291 81 8043 ONRAMP TO WB US-34 FROM 27TH ST GREELEY 44 325 68,123 210 8044 ONRAMP TO EB US-34 FROM SH-257 GREELEY 36 262 29,980 115 8045 ONRAMP TO EB US-34 BYPASS FROM SH-257 GREELEY 38 289 35,233 122 Subtotal 569 3,839 780,221 203

### 15 Table II-2 Denver RSD Sites

Site Code Location City Active Days Total Active Hours Registered Vehicles Measured Veh's Per Hour 2819 ONRAMP TO SB 121 FROM WB 287 WESTMINSTER 87 815 206,075 253 2821 ONRAMP TO NB I-25 FROM 120TH AVE WESTMINSTER 9 84 14,759 177 2971 EB DILLON RD EAST OF US-287 BROOMFIELD 54 381 118,851 312 8072 ONRAMP TO NB I-25 FROM 84TH AVE. THORNTON 5 61 11,552 189 8073 ONRAMP TO NB I-25 FROM 104TH AVE. NORTHGLENN 13 96 13,906 144 8087 ONRAMP TO WB I-70 FROM AIRPORT BLVD. AURORA 20 160 31,262 195 8088 ONRAMP TO WB I-76 FROM 88TH AVE COMMERCE CITY 12 97 12,445 128 8089 ONRAMP TO WB I-76 FROM 96TH AVE COMMERCE CITY 12 101 23,263 230 8090 ONRAMP TO EB I-76 FROM PECOS ST. DENVER 1 4 222 51 8091 ONRAMP TO WB I-76 FROM BROMLEY LN. BRIGHTON 6 35 4,163 119 8093 ONRAMP TO WB I-70 FROM NB I-25 DENVER 219 2,196 1,196,269 545 8103 ONRAMP TO WB I-270 FROM SB SH-2 COMMERCE CITY 2 13 721 56 8107 ONRAMP TO WB US-36 FROM BROADWAY DENVER 102 856 256,592 300 8115 ONRAMP TO EB I-76 FROM FEDERAL BLVD DENVER 7 64 7,536 118 8129 ONRAMP TO WB I-76 FROM PECOS ST DENVER 35 275 42,281 154 8098 ONRAMP TO NB I-225 FROM ILLIFF AVE AURORA 22 152 26,200 173 8120 ONRAMP TO SB I-225 FROM ALAMEDA AVE AURORA 24 191 27,896 146 2512 ONRAMP TO NB SH-157 FROM PEARL ST. BOULDER 8 51 7,350 145 2514 ONRAMP TO 96TH AVE FROM SH-42. BOULDER 41 269 54,507 202 2826 ONRAMP TO EB US-36 FROM MCCASLIN LOUISVILLE 35 227 29,450 130 8057 ON-RAMP TO SB SH 157 FROM PEARL ST. BOULDER 68 445 93,314 210 8064 ONRAMP TO NB SH 157 (FOOTHILLS PKAY) FROM EB TABLE MESA BOULDER 2 12 2,040 171 2166 ONRAMP TO WB I-76 FROM WB I-270 DENVER 3 22 1,272 59 2171 ONRAMP TO WB I-70 FROM PECOS ST. DENVER 1 1 177 185 2456 ONRAMP TO SB I-225 FROM PEORIA ST DENVER 21 155 30,739 198 2560 ONRAMP TO EB US-6TH AVE FROM SB I-25 DENVER 8 84 14,773 175 3499 ONRAMP TO SB I-25 FROM WB I-76 DENVER 4 22 7,431 340 3504 ONRAMP TO EB I-70 FROM PEORIA ST. DENVER 23 161 49,530 308 3505 ONRAMP TO WB I-70 FROM QUEBEC ST. DENVER 59 441 175,540 398 8062 ONRAMP TO EB I-70 FROM FEDERAL BLVD DENVER 4 48 8,481 177 8081 ONRAMP TO EB I-70 FROM HAVANA ST. DENVER 20 158 33,522 212 8094 ONRAMP TO SB US-285 (HAMPDEN AVE) FROM FEDERAL BLVD SHERIDAN 83 627 155,689 248 8097 ONRAMP TO WB US-6TH AVE FROM NB I-25 DENVER 171 1,222 864,160 707 8113 ONRAMP TO SB US-285 (HAMPDEN AVE) FROM SHERIDAN BLVD. DENVER 22 175 36,436 208 8122 ONRAMP TO NB I-25 FROM PARK AVE DENVER 126 1,173 391,149 334 8123 ONRAMP TO NB I-25 FROM 58TH AVE. DENVER 91 878 239,905 273 2319 ONRAMP TO EB C-470 FROM LUCENT BLVD HIGHLANDS RANCH 27 188 45,511 242 2320 ONRAMP TO EB C-470 FROM BROADWAY HIGHLANDS RANCH 7 51 23,147 455 2321 ONRAMP TO EB C-470 FROM UNIVERSITY BLVD HIGHLANDS RANCH 67 478 147,106 308 2322 ONRAMP TO WB C-470 FROM UNIVERSITY BLVD HIGHLANDS RANCH 38 295 75,304 255 2576 ONRAMP TO SB I-25 FROM EB COUNTY LINE RD. HIGHLANDS RANCH 33 230 52,309 227 2577 ONRAMP TO NB I-25 FROM EB COUNTY LINE RD. HIGHLANDS RANCH 105 754 314,992 418 8077 ONRAMP TO EB C-470 FROM QUEBEC ST. HIGHLANDS RANCH 95 652 340,218 522 8083 ONRAMP TO SB I-25 FROM FOUNDERS PARKWAY (EXIT 184) CASTLE ROCK 44 310 53,427 172 8084 ONRAMP TO SB I-25 FROM LINCOLN AVE. LITTLETON 17 113 14,001 124 8085 ONRAMP TO NB I-25 FROM WOLFENSBERGER RD. (EXIT 182) CASTLE ROCK 42 286 86,777 304 8086 ONRAMP TO NB I-25 FROM FOUNDERS PARKWAY (EXIT 184) CASTLE ROCK 39 261 73,439 281 2175 ONRAMP TO WB C-470 FROM KIPLING ST. LAKEWOOD 1 8 1,845 232 2176 ONRAMP TO WB C-470 FROM KEN CARYL AVE LAKEWOOD 93 620 155,578 251 2400 ONRAMP TO WB C-470 FROM NB US-285 (HAMPDEN AVE) LAKEWOOD 1 4 785 210 2458 ONRAMP TO WB US-6TH AVE FROM SIMMS ST LAKEWOOD 44 362 84,963 234 2461 ONRAMP TO WB US-6TH AVE FROM NB WADSWORTH BLVD LAKEWOOD 12 122 23,617 193

### 16 Table II-2 Denver RSD Sites continued

Table II-3 El Paso RSD Sites Site Code Location City Active Days Total Active Hours Registered Vehicles Measured Veh's Per Hour 8058 ONRAMP TO WB I-76 FROM SHERIDAN BLVD. ARVADA 44 330 68,067 206 8068 ONRAMP TO EB I-70 FROM HARLAN ST. ARVADA 1 8 1,492 178 8069 ONRAMP TO WB I-70 FROM KIPLING ST. WHEATRIDGE 65 535 131,941 247 8099 ONRAMP TO WB US-6TH AVE FROM SB WADSWORTH BLVD LAKEWOOD 2 9 1,351 146 8100 ONRAMP TO WB US-6TH AVE FROM SB KIPLING ST. LAKEWOOD 17 125 28,281 227 8104 ONRAMP TO SB US-285 (HAMPDEN AVE) FROM WADSWORTH BLVD. DENVER 10 83 7,634 92 8105 ONRAMP TO SB US-285 (HAMPDEN AVE) FROM KIPLING BLVD. DENVER 3 13 2,008 159 8106 ONRAMP TO NB US-285 (HAMPDEN AVE) FROM KIPLING BLVD. DENVER 68 706 156,954 222 8111 ONRAMP TO EB SH-58 FROM MCINTYRE ST. GOLDEN 65 597 162,453 272 8130 ONRAMP TO EB I-76 FROM SHERIDAN BLVD ARVADA 19 153 33,771 221 8131 ONRAMP TO EB I-70 FROM SHERIDAN BLVD. ARVADA 7 46 5,114 111 Subtotal 2,386 19,090 6,281,543 329

Site Code Location City Active Days Total Active Hours Registered Vehicles Measured Veh's Per Hour 2518 ONRAMP TO E.PLATTE AVE FROM NB ACADEMY BLVD COLORADO SPRINGS 8 53 7,876 148 2520 ONRAMP TO NB I-25 FROM N.ACADEMY BLVD COLORADO SPRINGS 10 56 8,604 153 Subtotal 18 109 16,480 151

Total 2,973 23,038 7,078,244 307

### 17 

### Figure II-2 a: Site Locations Northern Front Range

### 18 

### Figure II-2 b: Site Locations – Denver Metro Area

C. Sources of Data and Description of Elements Data used in the analyses in this re port come from three primary sources:

 Remote sensing unit measurements

 The DMV database maintained on the AI R program contractor host computer

### 19 

###  I/M test database maintained on the AIR program contractor host computer
Data from the RSD units are loaded into a database maintained by the centralized contractor, Envirotest. Using th e vehicle plate identified by RSD, the registration file is accessed to determine the vehicle identifica tion number (VIN) and vehicle registration information. Envirotest uses the Polk VIN Decoder to add additio nal information about each vehicle. The combined data fields are shown in Table II-4.

Table II-4 Vehicle Measurement Information 

### Field Name Description V_DATA_VER Data version V_DATE_TIME Date and time of measurement V_RSD_UNIT RSD system number V_SEQ_NUM Measurement sequence number V_SITE_CODE Site reference V_PROGRAM_CODE I/M Program V_VAN_OPERATOR_ID V_CO Carbon monoxide emissions % V_CO2 Carbon dioxide emissions % V_MAX_CO2 Maximum observed CO2 V_CO2_VOLUME Volume of CO2 observed V_HC Hydrocarbon emissions ppm hexane equivalent V_NOX Oxides of nitrogen emissions ppm (NOx) V_NOX_FLAG Validity of NOx measurement V_OPAC Opacity measurement V_SPEED Speed MPH V_ACCEL Acceleration MPH/S V_SA_UNITS Units of speed and acceleration V_TEMPERATURE Ambient temperature V_HUMIDITY Ambient humidity V_WIND_SPEED Ambient wind speed V_WIND_DIRECTION Ambient wind direction V_WEATHER_UNITS V_PLATE_CONFIDENCE Reserved for future use V_ALPR_VENDOR Reserved for future use V_TEST_COUNTY Reserved for future use V_CRC V_TAG_EDIT_MODE V_TAG_EDIT_ID_1 V_TAG_EDIT_ID_2 V_TAG_EDIT_ID_3 V_TAG_EDIT_EMP_1 V_TAG_EDIT_EMP_2 V_TAG_EDIT_EMP_3 V_PLATE License plate V_PLATE_STATE State issuing license plate V_PLATE_TYPE Type of plate V_VIN Vehicle Identification Number

### 20 

### Field Name Description V_LZIP Zip code for legal owner address V_STATE_MAKE Make code V_STATE_MODEL Model code V_COUNTY County of registration V_VEH_YEAR Model year V_EM_FLAG Subject to emissions test V_POLK_VEH_YEAR Polk decoded model year V_POLK_MAKE Polk decoded make V_POLK_VEH_TYPE Polk decoded vehicle type (P-pass, T-truck, U-unknown) V_POLK_MODEL Polk decoded model V_POLK_DISP Polk decoded engine displacement V_VSP Calculated vehicle speci fic power during measurement

### 21 

## III. Summary of Data Collection Up to 22 remote sensing units were depl oyed for 2,973 days during 2013 to collect 7.1M measurements having a visible plate and valid HC, CO, speed and acceleration values: 6.3M measurements in the Denver metropolitan area (DMA) Metro Area, 780 ,000 measurements in the Northern Front Range (NFR) and 16,000 measurements in El Paso County. Clean screen exemption notices were issued for 263,432 vehicles scheduled to renew their registration in 2013 and due for emissions testing (Table III-1) comprising 221,334 DMA vehicles and 42,097 NFR vehicles. Vehicles registered in th e DMA accounted for over 5.6M measurements, the NFR for 743,000, and El Paso County 108,000. Another 253,000 measur ements were of vehicles registered in other Colorado countie s (Table III-2). In 2012, RSD performed 6.7 million emission m easurements and 280,310 clean screens were issued.

Table III-1 Collection Summary



### A. Monthly Collection Activity Figure III-1 shows the monthly RS D measurements. Collection rates were lower during severe winter months. B. Measurements by Hour of Day Figure III-2 ‘Measurements by H our of Day’ shows the number of vehicles measured during each hour of the day. The shape of the curve is indicative of when measurements were collected and does not represent the level of traffic during the day. Most measurements were collected between 7:00am and 7:00pm. Statistic Denver Metro Area Northern Front Range Colorado Springs Total Sites Used 63 28 2 93 Collection Van Days 2,386 569 18 2,973 Active Collection Van Hours 19,090 3,839 109 23,038 Matched to Registration 6,281,543 780,221 16,480 7,078,244 Notices Generated for 2013 renewals 221,334 42,097 263,431

### 22 

### Figure III-1 Monthly RSD Measurements

Figure III-2 Measurements by Time of Day 0 100,000 200,000 300,000 400,000 500,000 600,000 700,000 800,000 900,000 1,000,000JanFebMarAprMayJunJulAugSepOctNovDecMeasurements 

### Measurements by Month

El Paso County

Northern Front Range

Denver Metro Area



### 0 100,000 200,000 300,000 400,000 500,000 600,000 700,000 800,000 900,000Before 6 am6-7 am7-8 am8-9 am9-10 am10-11 am11-12 am12 -1 pm1-2 pm2-3 pm3-4 pm4-5 pm5-7 pm6-7 pm7-8 pmMeasurements 

### Measurements by Time of Day

El Paso County

Northern Front Range

Denver Metro Area

### 23 

### C. Composition of Vehicles Measured Table III-2, Source of Vehicle Re gistrations Measured by RSD, shows the number of vehicles registered in each program area and the area wher e they were measured. The majority (98%) of Denver Metropolitan Area registered vehicles were measured w ithin the DMA. A majority (79%) of Northern Front Range registered vehicl es were measured in NFR with the remaining 21% being measured in the DMA. Table III-3, Type of Vehicles Measured by RSD within Registration Jurisdiction, shows that 79.8% of vehicles measured were registered in the DMA, 10.5% in the NFR, 1.5% in El Paso County (Colorado Springs), 3.6% in other non-I/M counties, and 4.6% were not matched. This can occur when plates are transferred by an owner to a new vehicle. These numbers are indicative of on-road activity – not unique registrations. The sa me vehicle may be measured more than once.
Table III-4 shows the distribut ion of vehicle measurements by vehicle type, age group and registration jurisdiction. The vehi cle types were identified by the Polk VIN decoder. The model years of 1980 and older vehicles and some of th e newest models were determined from the registration information but the vehicle type wa s not available. These were classified as Unknown in Table III-3. One thousand and fifty- one measurements of motorcycles were also recorded.

Table III-2 Source of Vehicl e Registrations Measured by RSD 

### Measured In Denver Metro Area Northern Front Range El Paso Adams 864,222 97% 25,472 3% 171 0% 889,865 Arapahoe 735,400 97% 18,545 2% 443 0% 754,388 Boulder 254,639 91% 25,191 9% 54 0% 279,884 Broomfield 145,837 97% 3,772 3% 17 0% 149,626 Denver 1,001,642 98% 20,474 2% 453 0% 1,022,569 Douglas 792,648 99% 8,379 1% 406 0% 801,433 Jefferson 1,694,294 99% 16,974 1% 216 0% 1,711,484 State of Colorado 34,896 87% 4,925 12% 326 1% 40,147 Subtotal Denver Metro 5,523,578 98% 123,732 2% 2,086 0% 5,649,396 Larimer 52,049 13% 349,857 87% 63 0% 401,969 Weld 102,899 30% 238,738 70% 52 0% 341,689 Subtotal Northern Front Range 154,948 21% 588,595 79% 115 0% 743,658
El Paso El Paso 88,199 81% 7,484 7% 12,813 12% 108,496
Non I/M 228,114 90% 24,015 9% 785 0% 252,914 Not Matched 323,780 Total 5,994,839 743,826 15,799 7,078,244 

### Registered

Count y Total

Northern Front Range Denver Metro Area 

### Program

### 24 Table III-3 Type of Vehicles Measured by RSD within Registration Jurisdiction

Table III-4 Registered Jurisdiction and Age of Vehicles Measured by RSD 

### Program County Pass Truck Unknown Total % Adams 342,518 543,312 4,035 889,865 12.6% Arapahoe 298,728 452,936 2,724 754,388 10.7% Boulder 123,825 154,957 1,102 279,884 4.0% Broomfield 63,807 85,382 437 149,626 2.1% Denver 423,627 593,954 4,988 1,022,569 14.4% Douglas 275,290 524,629 1,514 801,433 11.3% Jefferson 664,064 1,041,676 5,744 1,711,484 24.2% State of Colorado 10,134 27,952 2,061 40,147 0.6% Denver Metro 2,201,993 3,424,798 22,605 5,649,396 79.8% Larimer 159,649 240,134 2,186 401,969 5.7% Weld 132,518 207,381 1,790 341,689 4.8% Subtotal North Front Range 292,167 447,515 3,976 743,658 10.5%
El Paso El Paso 44,634 63,022 840 108,496 1.5%
Non I/M 87,634 162,314 2,966 252,914 3.6% Not Matched 323,780 4.6%
Total 2,626,428 4,097,649 30,387 7,078,244 100.0% Denver Metro

Northern Front Range



### Vehicle

Type Model Year Denver Metro Area Northern Front Range El Paso NonI/M Total Pass 1981 & older 279 46 18 45 388 1982-1990 31,028 5,224 761 2,056 39,069 1991-1995 114,582 17,789 2,456 5,872 140,699 1996-2000 374,788 52,498 7,442 15,992 450,720 2001-2005 651,081 90,678 13,540 27,185 782,484 2006-2010 656,463 84,211 13,163 24,525 778,362 2011 & newer 373,772 41,721 7,254 11,959 434,706 Light Truck 1981 & older 409 86 13 126 634 1982-1990 27,146 5,053 646 2,766 35,611 1991-1995 108,010 16,889 2,425 7,381 134,705 1996-2000 480,961 64,364 8,781 25,025 579,131 2001-2005 1,051,982 138,572 19,945 49,776 1,260,275 2006-2010 1,107,505 141,135 20,405 50,151 1,319,196 2011 & newer 648,785 81,416 10,807 27,089 768,097 Unknown 1981 & older 10,619 1,920 354 1,358 14,251 1982-1990 364 91 43 135 633 1991-1995 562 111 32 113 818 1996-2000 1,516 328 52 300 2,196 2001-2005 2,806 514 102 313 3,735 2006-2010 2,841 530 109 355 3,835 2011 & newer 2,872 346 57 181 3,456 Motorcycles 613 136 91 211 1,051 Total 5,648,984 743,658 108,496 252,914 6,754,052

### 25 

## IV. Clean Screening Program Performance A. Vehicles Selected, Notices and Redemptions

In 2013, there were 273,824 vehicles qualifying for pa rticipation in the cl ean screen program. Table IV-1 summarizes the monthly number of vehi cles meeting screening criteria each month, including the number withheld for the random sample and the number rejected through QA checks.
A random sample of two percent of vehicles meeting Clean Screen criteria are not mailed notices. These vehicles are required to go to a te st station to obtain the station-based emission inspection. This random sample of vehicles is us ed to evaluate the effectiveness of the Clean Screen program.
Not all vehicles notified for clean screen or w ithheld in the random sample redeem the clean screen or obtain a test at that time, for exam ple vehicles changing owner were likely to have obtained an earlier station inspection. Compared to the 263,431 vehicles notified in the year, fewer vehicles 233,760 (88.7%) obtained a clean screen.

Table IV-1 Vehicles Qualified As Mee ting Clean Screening Criteria by Status



### Table IV-2 lists the number of vehicles by month and city notified via the Department of Revenue. Table IV-3 shows insp ection results of the audit sample. Just 0.6% of the audit sample failed their exhaust emissions inspection down from 0.9% in 2012. Gas cap pressure test failures of 3.4% were up from 3.3% in 2012. Reg Year Reg Month Random Sample QA failed Notified Total Qualified Random % of Qualified 2013 Jan 482 787 22,880 24,149 2.0% 2013 Feb 462 463 22,235 23,160 2.0% 2013 Mar 486 272 23,425 24,183 2.0% 2013 Apr 432 242 20,840 21,514 2.0% 2013 May 450 324 21,660 22,434 2.0% 2013 Jun 463 274 22,577 23,314 2.0% 2013 Jul 494 293 23,362 24,149 2.0% 2013 Aug 497 361 23,961 24,819 2.0% 2013 Sep 484 615 22,332 23,431 2.1% 2013 Oct 496 559 23,770 24,825 2.0% 2013 Nov 393 414 18,539 19,346 2.0% 2013 Dec 363 287 17,850 18,500 2.0% Total 5,502 4,891 263,431 273,824 2.0%

### 26 Table IV-2 Notifications Transmitted to DOR

Table IV-3 Clean Screen Audit Test Pass / Fail Statistics Registration Renewal Month City Jan Feb Mar Apr May Jun Jul A ug Sep Oct Nov Dec Total DENVER 3,743 3,539 4,033 3,559 3,808 4,125 4,291 4,112 3,888 4,067 3,390 3,339 45,894 AURORA 1,680 1,553 1,656 1,479 1,435 1,442 1,511 1,655 1,431 1,634 1,235 1,197 17,908 LITTLETON 1,262 1,245 1,264 1,175 1,140 1,335 1,390 1,447 1,257 1,454 1,102 1,102 15,173 FT COLLINS 1,247 1,153 1,259 1,126 1,191 1,222 1,201 1,311 1,195 1,342 1,027 895 14,169 ARVADA 1,062 1,112 1,149 1,093 1,132 1,228 1,271 1,348 1,252 1,349 1,011 1,030 14,037 LAKEWOOD 1,097 1,080 1,127 1,040 1,093 1,094 1,122 1,241 1,266 1,293 1,044 988 13,485 HIGHLAND RCH 998 1,092 1,041 908 1,008 971 1,080 1,181 1,106 1,176 842 821 12,224 WESTMINSTER 961 833 910 776 795 905 883 903 855 831 682 715 10,049 THORNTON 893 874 893 782 869 859 820 836 752 859 643 625 9,705 CENTENNIAL 800 769 819 703 697 716 750 805 807 835 728 615 9,044 CASTLE ROCK 676 622 664 560 600 683 716 688 684 673 528 476 7,570 GREELEY 554 610 663 611 593 572 653 619 577 627 457 409 6,945 BROOMFIELD 683 671 664 568 614 591 596 584 540 544 440 428 6,923 BOULDER 777 708 645 598 550 588 577 564 478 516 346 423 6,770 LOVELAND 507 560 609 528 600 579 568 581 575 596 429 376 6,508 GOLDEN 538 495 471 437 473 539 570 573 521 604 493 452 6,166 PARKER 548 498 533 477 480 492 528 559 521 548 406 411 6,001 LONGMONT 427 459 469 376 414 377 402 389 316 371 275 263 4,538 ENGLEWOOD 387 374 375 383 365 351 377 430 371 383 267 316 4,379 WHEAT RIDGE 238 238 266 266 253 230 252 267 293 274 221 237 3,035 BRIGHTON 252 244 271 236 246 224 234 235 236 244 214 192 2,828 NORTHGLENN 277 250 240 253 250 260 255 242 186 263 177 153 2,806 WINDSOR 226 204 238 211 228 231 272 282 275 245 201 157 2,770 COMMERCE CITY 227 230 227 183 196 207 221 251 214 217 175 128 2,476 LAFAYETTE 171 170 177 171 160 189 209 198 183 212 153 143 2,136 LOUISVILLE 166 180 167 145 152 168 186 174 172 183 135 130 1,958 ERIE 178 175 199 165 179 170 174 162 156 157 102 123 1,940 EVERGREEN 141 137 148 126 172 159 179 176 151 165 133 150 1,837 MORRISON 175 148 124 125 131 148 151 137 139 161 103 111 1,653 GREENWOOD VLG 139 130 138 108 150 130 119 156 165 166 108 97 1,606 LONE TREE 153 143 133 116 114 128 103 142 116 145 103 103 1,499 EVANS 104 138 133 106 127 125 117 113 110 104 103 84 1,364 CASTLE PNS N 106 114 114 100 100 138 126 145 100 123 108 86 1,360 JOHNSTOWN 96 89 104 100 96 100 112 110 122 109 93 81 1,212 SUPERIOR 104 121 113 69 90 87 91 105 90 73 86 80 1,109 FREDERICK 80 71 88 66 61 88 94 110 104 107 82 88 1,039 BERTHOUD 90 79 92 79 77 72 71 69 75 65 55 56 880 FIRESTONE 70 100 83 57 61 77 73 66 71 95 63 45 861 CONIFER 78 99 82 61 76 69 63 57 63 65 54 42 809 OTHER 969 928 1,044 918 884 908 954 938 919 895 725 683 10,765 Total 22,880 22,235 23,425 20,840 21,660 22,577 23,362 23,961 22,332 23,770 18,539 17,850 263,431

Vehicle Type Vehicles Fail Emissions Fail Gas Cap / Pressure Fail Inspection Passenger 1,827 9 68 75 Light Truck 2,633 18 85 102 Total 4,460 27 153 177 Percentage 0.6% 3.4% 4.0%

### 27 

### B. Clean Screen Program Effectiveness The emissions reductions obtained during the station testing of the audit samp le vehicles are used to project the total emissions re ductions foregone as a result of the Clean Screen program.
Pass / Fail Statistics Matching initial tests for audit vehicles were limited to those occurring after the second RSD measurement and before expiration of the assigned Clean Screen period. Matching reinspections following an initial failure were sought through the end of February 2014. The inspections identified for audit sample vehicles and the inspection results are tabulated in Table IV-3. As noted earlier, some of the anticipated random vehicles did not obtain a test within the Clean Screen period. In aggregate, 0.6% of th e tested audit vehicles failed their tailpipe emissions inspection, and 3.4% of the tested audi t vehicles failed their gas cap pressure test 2



### . Following sections describe in detail how these resu lts are used to evaluate the emissions impact of the Clean Screen program.

Tailpipe Emissions Over 93% of inspected vehicles, and 95% of the clean screen audi t vehicles, were tested using IM240. Models inspected using the idle test included 1981- and-older models and 1982-andnewer trucks over 8500 lbs GWWR plus some fou r-wheel drive and traction control vehicles. Few of these were clean screened. The IM240 te st provides a more accurate estimate of in-use vehicle exhaust emissions than the idle tailpipe te st. Therefore, the resu lts of the clean screen audit sample vehicles tested using IM240 were used to evaluate the exhaust emissions effectiveness of the clean screen program.
Vehicle test results were sorted by VIN and test date. Vehicles we re then further classified based on their first and last test result during th e period. To avoid potential double counting of emissions reductions, the emissions analysis only considered the first and last result for each vehicle during the year and inte rim results were ignored. In the list below, the first and last results are in dicated in parenthesis, where P is pass, F is fail, W is waiver and null indicates th ere was only a single test result for a particular vehicle. The expected combinations applying to the va st majority of vehicles are underlined.

 P – Passed initial test (P/null, P/P, P/F, P/W)

 R – Failed and successfully repaired (F/P)

 U – Failed unresolved (F/null, F/F)

 W – Failed and wavered (F/W)

2 Note that the number of emissions fails plus the number of Ga s Cap / Gas Cap Pressure failures does not always equal the total

number of inspection failures. In a few cases a vehicle may fail both Emissions and Gas Cap. In a few cases, vehicles fail fo r other reasons.

### 28 

### The difference between the initial and final tests is used to determine the percentage of tailpipe emissions reduction of each group. Fo r vehicles with only one test, the final result is the same as the initial result. Adjustment of Fast-Pass Results A majority of vehicles tested on IM240 fast pass the test in less than the 240-second driving cycle. To allow for comparison of emissions of vehicles tested over different durations of the IM240 test cycle, the emission results for vehi cles fast-passing the IM240 inspection must be extrapolated. A method for projecting full test emissions was developed and implemented in the I/M program in 1996 4 

### and the projected full test emissions values are stored in the test records and reported as the emissions results.
Unresolved Vehicles When vehicles fail their initial in spection, they must obtain a repair and return for re-inspection. This process is normally completed in 30 days, bu t can take longer. Vehi cles having initial tests in late 2013 but completing repair and final test after February of the following year are treated as unresolved. Thus, the “Fail unresolved ” category may be somewhat over-stated. A number of vehicles never complete the repair /re-inspection process. In most cases, these vehicles are either scrapped or removed fr om the non-attainment area, which does reduce emissions in the area. Surveys in Arizona 5 

### and Colorado 6 

### found that some vehicles continued to operate in the area in violation of the program rules, either with expired lic ense plates or with stolen license plates or license plate stickers. In this report, it is assumed that two-thirds of these unresolved vehicles leave the area and one th ird continues to operate. Recent studies in Colorado indicate the percentage leaving the area may be as high as 80%.
To minimize the number of unresolved Clean Screen audit vehicles, retests of audit vehicles were included through the end of February 2014 and the audit ve hicles were all assumed to remain in the area.
First and Final Emissions Results Table IV-4 contains an example of the initial and final tailpipe results for 1982 to 1985 passenger vehicles inspected using the IM24 0 test. The table shows the av erage initial and average final emissions for each group of vehicles t ogether with the percentage reduction. For example, of the 1,428 1985 model year passenge r vehicles tested using the IM240 transient test, 15.8% of vehicles initially failed inspection and were repair ed (Pass) with HC, CO and NOx reductions of 50.7%, 68.7% and 8.8%. Another 7.4% of vehicles failed their initial inspection and had not successfully passed a retest by end February 2014 (Unresolved). Reductions from these vehicles are estimated to be approximate ly 66% for HC, CO and NOx, because follow-up studies have shown that more than two thirds cease operating in the area. Finally, 0.1% of vehicles were waived (Waiver) with CO reducti ons of 35.6% and increases in HC and NOx. In aggregate, including vehicles passing their initial inspection, emi ssion reductions for 1985 passenger vehicles were 24.9% for HC, 35.6% for CO and 6.2% for NOx. Complete tables by model year and vehicle type are provided in Appendix A for vehicles tested using the IM240. Tables are also provided fo r the Clean Screen audit sample vehicles.29Table IV-4 Transient Test Emission Reductions for 1982-1985 Passenger VehiclesAppendix A1 Colorado 2013 Transient Test Emissions ReductionsUnresolved fails remaining in area 33%Model First Last Initial Final Reduction %Year/Type Result Result Vehicles Fail% HC CO NOX HC CO NOX HC CO NOX1982 Pass - 258 1.62 19.18 2.02 1.62 19.18 2.02 0.0% 0.0% 0.0%P Fail Pass 59 17.2% 4.56 51.09 2.02 1.52 19.35 1.88 66.6% 62.1% 7.0%Fail Unresolv. 26 7.6% 5.59 85.27 1.92 1.99 29.03 0.65 64.4% 66.0% 66.0%Fail Waiver 1 0.3% 1.49 70.11 0.38 1.49 70.11 0.38 0.0% 0.0% 0.0%Total Fail% 344 25.0% 2.42 29.80 2.00 1.63 20.10 1.88 32.7% 32.5% 6.0%1983 Pass - 462 1.29 12.26 2.07 1.29 12.26 2.07 0.0% 0.0% 0.0%P Fail Pass 98 16.0% 2.32 36.51 2.06 1.24 14.85 1.79 46.7% 59.3% 13.2%Fail Unresolv. 49 8.0% 4.46 73.11 1.91 1.56 24.31 0.57 65.1% 66.7% 69.9%Fail Waiver 3 0.5% 4.50 140.30 1.08 4.73 146.55 0.24 -5.0% -4.5% 77.6%Total Fail% 612 24.5% 1.73 21.65 2.05 1.32 14.30 1.89 23.5% 33.9% 7.5%1984 Pass - 619 1.23 11.35 1.92 1.23 11.35 1.92 0.0% 0.0% 0.0%P Fail Pass 147 17.3% 2.86 39.51 1.97 1.44 14.26 2.05 49.7% 63.9% -4.4%Fail Unresolv. 79 9.3% 5.47 75.77 1.82 1.73 23.32 0.59 68.4% 69.2% 67.3%Fail Waiver 6 0.7% 5.14 112.15 1.64 4.98 116.14 1.55 3.2% -3.6% 5.9%Total Fail% 851 27.3% 1.94 22.90 1.92 1.34 13.70 1.82 30.7% 40.2% 5.2%1985 Pass - 1,094 1.05 10.84 1.89 1.05 10.84 1.89 0.0% 0.0% 0.0%P Fail Pass 226 15.8% 2.21 31.01 2.12 1.09 9.71 1.93 50.7% 68.7% 8.8%Fail Unresolv. 106 7.4% 3.92 58.15 1.79 1.34 19.49 0.58 65.8% 66.5% 67.5%Fail Waiver 2 0.1% 5.59 85.44 1.10 11.43 58.43 1.41 -104.5% 31.6% -27.3%Total Fail% 1,428 23.4% 1.45 17.65 1.92 1.09 11.37 1.80 24.9% 35.6% 6.2%

### 30 

### Audit Sample Reductions and Projected Impact Table IV-5 shows the aggregate first and final results for the 95% of inspected audit sample vehicles tested using IM240. The average per vehicle emissions reductions from the audit sample are multiplied by the number of exempted clean screen vehicles to project the reductions that could have been achieved if the clean screen vehicles had instead been inspected at the stations. This amount is then compared to the total emission reductions from vehicles tested at stations to determine th e impact of the Clean Screen program and the percentage of emissions reductions retained. For vehicles subject to the IM240 test, the Clean Screen program retained 98.4%, 96.9% and 98.1% of the exhaust HC, CO and NOx reductions respectively. These reductions assume all vehicles are driven the same number of miles each year. Mileage adjusted emission reductions are calculated in section V.

Table IV-5 Clean Screen Emissions Impact for Tailpipe Emissions



### C. Gas Cap Evaporative Emissions The evaporative emissions test used in the I/M Program is a gas cap pressure test. Leaking gas caps allow evaporated gasoline (HC) to escape from vehicle gas tanks into the Vehicles HC g/mi CO g/mi NOx g/mi Audit Sample 4,234 Mean Initial 0.093 1.744 0.277 Mean Final 0.090 1.638 0.272 Emissions reduction 0.004 0.106 0.004

Clean Screens 222,368 Potential Reductions 863 23,507 992

Station Vehicles 869,433 Mean Initial 0.290 3.967 0.623 Mean Final 0.229 3.132 0.564 Emissions reduction 0.061 0.835 0.059

In station reductions 53,088 726,166 51,003

Combined CS & Stn 1,091,801 53,951 749,673 51,995 Clean Screen Impact 1.6% 3.1% 1.9% Retained Reductions 98.4% 96.9% 98.1%

### 31 

### atmosphere. The impact of leaking gas caps on the Clean Screen progra m is only evaluated in this report in terms of the failure rate, not in terms of repairable gas cap emissions reductions 3



### . Figure IV-1 compares the average gas cap fail ure rate of the Clean Screen audit sample vehicles to the average failure ra te of the non-audit vehicles tested at stations. The failure rate of vehicles exempted via Clean Screen met hods was 15% lower than the failure rate of vehicles receiving a station-base d test (See Figure IV-1). Th is result is expected because remote sensing is directed towards measuring tail pipe emissions. A gas cap evaporative leak has to be quite large to be detected by RSD units . Clean screen models were newer than the overall tested fleet. Figure IV-1 Gas Cap Pressure Failure Rates

Using the fail rates identified in the audit sample, Table IV-6 shows the projected gas cap failures that would have been found in the exem pted clean screen vehicles. These projected gas cap failures are added to the actual gas cap failures identified in initial inspections at the test stations to provide the total possible gas cap failure rate for the program. Vehicle counts in Figure IV-6 are higher than IV-5 because they include gas cap tests on vehicles tested using idle tests as well as those test ed using IM240. Vehicles with a redeemed Clean Screen notice account for 17.1% of the total pos sible gas cap failures. Theref ore, 82.9% of evaporative gas cap HC emission reductions were retained.

3 Although the gas cap leak rates ar e measured in the I/M Program, it is not clear that leak rates are directly related to the

amount of evaporative HC emissions releas ed from the gas tank. A small pressure leak may have the same effect as a large pressure leak, as long as it is sufficient to release internal gas tank pressure over a period of an hour or so. 

### 0.0% 0.5% 1.0% 1.5% 2.0% 2.5% 3.0% 3.5% 4.0% 4.5%

Pressure Failure Missing Cap
Nature of Failure 

## 2013 Gas Cap Pressure Failure Rates

Clean Screen Station

### 32 

### In general, it is desirable to use direct measurements of emissions to evaluate program performance rather than a model. Unlike exhaust emissions that are directly measured using tailpipe tests, however, emissions rates from gas caps cannot easily be directly measured. Emissions rates of vapor leaks are typically de termined in a test laboratory by enclosing a vehicle in a sealed compartment and measuring the emissions released into the compartment over time, which is impractical for testing many vehicles. Therefore, the EPA mobile source emissions model, MOVES, was used to estimat e the fraction of emissions benefits derived from gas cap inspections. CDPHE provided results from MOVES models of the benefits of the I/M program for 2013. The projected average reduction in HC emissions of the area fleet was 0.128 g/mi. This was comprised of 0.118 g/mi resulting from exhaus t emissions inspections and 0.010 g/mi from the Gas Cap testing. The measured I/M exhaus t reductions (see secti on V) were 498.8 tons. Assuming the 0.118 g/mi corresponded to 498.8 tons , the Gas Cap related HC reductions were projected to be 40.8 tons. These results are sh own in Table IV-7. The RapidScreen impact was projected as 7.0 tons or 1.3% of the I/M program reductions.

Table IV-6 Clean Screen Impact on Evaporative HC Emissions

Table IV-7 Gas Cap Related Benefit Tons 

### Initial Tests Pressure Failure Missing Cap Total Fails RapidScreen Audit 4,460 149 4 153 3.3% 0.1% 3.4%


### Projected RapidScreen 233,760 7,809 210 8,019

Station GC Tests 958,107 37,491 1,345 38,836 3.9% 0.1% 4.1% 

### Total Program 1,191,867 45,300 1,555 46,855 RapidScreen Impact 19.6% 17.2% 13.5% 17.1% Retained Reductions 80.4% 82.8% 86.5% 82.9%

MOVES Estimates (from CDPHE) 2013 MOVES g/mi HC I/M 2013 HC tons I/M Exhaust emission reductions 0.118 498.8 Projected Gas Cap Evap Emissions reductions 0.010 40.7 I/M Program total HC reductions 0.128 539.6
Gas Cap Evap RapidScreen impact 17.1% 0.002 7.0 % of I/M program HC benefit 1.3%

### 33 

### D. Hybrid RSD-LEI vs. 2-hit RSD Envirotest compared the effectiveness of th e ‘Hybrid’ and ‘2-RSD’ screening methods. The Hybrid method uses a single RSD measurement and a low emitter index (LEI) table. The 2- RSD method uses two RSD measurements. The audit sample of vehicles with IM240 tests contained 2,832 ve hicles screened using the 2- RSD method and 1,402 vehicles screened using Hybrid RSD-LEI method. Table IV-8 shows the emissions reductions for these two samples a nd the average for all vehicles inspected at stations. Figures IV-2 and IV -3 show the average initial em issions and emissions reductions for each sample.
The 2-RSD method audit vehicles had initial em issions that were 41%, 53% and 54% of the overall I/M fleet average for HC and CO a nd NOx respectively. These percentages were similar to the equivalent percentages in 2012 of 42%, 50% and 56% respectively. The Hybrid RSD-LEI method audit vehicles had lower initial em issions that were 30%, 44% and 42% of the I/M fleet average for HC and CO and NOx respectively. These percentages were higher than the 2012 equi valents of 26%, 38% and 39% Average I/M emissions reductions for the 2-RSD audit vehicles were 1.9%, 3.5% and 0.7% of fleet average initial emissions for HC and CO and NOx respectively. The comparable percentages in 2012 were 3.8%, 3.4% and 3.0%. Average emissions reductions for the Hybrid RSD- LEI audit vehicles were 0.8%, 2.1% and 1.1% of fleet average initial emissions fo r HC and CO and NOx respectively. The comparable 2012 percentages were 0.8%, 0.9% and 0.1%. Average reductions in station tested vehicles were 24.4%, 23.9% and 10.7% for HC, CO and NOx respectively. The Hybrid RSD-LEI audit vehicles had lowe r initial emissions of HC, CO and NOx and smaller reductions than the 2-RSD audit vehicles . Consideration should be given to adjusting the 2-RSD standards. The RSD-LEI method sta ndards are in part automatically adjusted by annual updates to the LEI table.

### 34 Table IV-8 Average Emissions per Vehicle



### Figure IV-2 Average In itial IM240 Emissions Vehicle IM240 Tailpipe Emissions Sample Vehicles HC g/mi CO g/mi NOx g/mi I/M vehicle initial mean emissions 0.248 3.496 0.549

2-RSD Audits 2,832 Mean Initial 0.103 1.845 0.299 Mean Final 0.098 1.723 0.296 Emissions reduction 0.005 0.122 0.004 % of I/M vehicle initial mean emissio n 1.9% 3.5% 0.7%
Hybrid Audits 1,402 Mean Initial 0.075 1.540 0.231 Mean Final 0.073 1.466 0.225 Emissions reduction 0.002 0.074 0.006 % of I/M vehicle initial mean emissio n 0.8% 2.1% 1.1%

All Station Tests 869,433 Mean Initial 0.290 3.967 0.623 Mean Final 0.229 3.132 0.564 Emissions reduction 0.061 0.835 0.059 % of I/M vehicle initial mean emissio n 24.6% 23.9% 10.7%

0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35Station2-RSDRSDLEIg/mi HC

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5Station2-RSDRSDLEI 

### CO

0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70Station2-RSDRSDLEI 

### NOx

### 35 

### Figure IV-3 Average IM240 Emissions Reductions

0.00 0.02 0.04 0.06 0.08Station2-RSDRSD-LEIg/mi HC

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9Station2-RSDRSD-LEI 

### CO

0.00 0.02 0.04 0.06 0.08 0.10Station2-RSDRSD-LEI 

### NOx

### 36 

## V. Estimate of Overall I/M Progr am Benefits and Clean Screen Impact
Overall I/M program emission reductions derive from two main components:

○ Reductions resulting directly from I/M inspections and consequent repairs;

○ Reductions from repair activities performe d in anticipation of an I/M inspection. In previous years, it was assu med the vast majority of emi ssions reductions were directly measurable by comparing the initial and final I/ M inspection emissions results, i.e. the first component described above. This report us es the same methodology. However, most vehicles tested were equipped with OBD-II ma lfunction indicator lights and many repairs of these vehicles are performed in response to warn ing lights before the initial inspection. The benefits of these repairs are not directly measurable in the program testing. The Clean Screen disbenefit can be projected dire ctly from the emissions testing of the audit sample. There may be unmeasured offsetti ng benefits if the Clean Screen program encourages owners to maintain malfunctio ning vehicles sooner than otherwise. For this report, measured I/M exhaust emissions benefits were project ed from the IM240 and Idle emissions tests. In the case of Idle tests, idle test emission concentrations were converted to equivalent IM240 g/mi emissions. For each model year, the IM240 g/mi emissions values were weighted by the annual vehicle miles traveled to project the emissions inventory for initial and final test and, hence, the direct program benefits. The following sections project the directly measured tons of emissions and reductions
A. Conversion of Idle Tests to IM240 Equivalent emissions On-road remote sensing emissions of vehicles in spected at I/M stations have been used to project IM240 equivalent valu es for Idle test emissions. The idle test procedure includes a low-speed id le and a high speed idle at 2500rpm. Vehicles model year 1980 and older are required to pa ss the low-speed idle while 1981 and newer models must pass both the low-sp eed and the high-speed tests. Figures V-1 and V-2 show the correlation be tween Idle tests and on-road HC and CO emissions of the same vehicles. Results are averaged by model year. Average initial and final test emissions were used for vehicles initially failing a nd retested. Model years were grouped together for 1965-and-older, 1966 to 1970, 1971 to 1975, 1976 to 1981, 1982 to 1985, 1986 to 1990 and 2004-and-newer. Even with these groups, there we re less than 100 matching RSD measurements for Passenger vehi cles in groups from 1982 to 1998. There were several hundred matching RSD measuremen ts for each truck group. Trend lines were plotted with an intercept of zero to obtain RSD / Idle Test emissions ratios.

### 37 

### Similarly, Figure V-3 shows the correlation between IM240 and on-road emissions. Trend lines were plotted with an intercept of zero for HC and CO emissions to obtain IM240 / RSD emissions ratios. The results are summarized in Tables V-1 and V-2. Figure V-1 RSD vs. Idle Test Emissions

Table V-1 Low Speed Idle to IM240 Truck Idle Test and Matchin g Vehicle RSD Emissions (RSD N=57,867)

y = 1.0336x R 2 = 0.9242

0 100 200 300 400 500 600 700 800 900

0 100 200 300 400 500 600 700 800 Idle HC ppmRSD HC ppm Passen g er Idle Test and Matchin g Vehicle RSD Emissions (RSD N=8,843)

y = 1.1007x R 2 = 0.8169
0 100 200 300 400 500 600

- 100 200 300 400 500 600 Idle HC ppmRSD HC ppm Passen g er Idle Test and Matchin g Vehicle RSD Emissions (RSD N=8,843)

y = 1.3267x R 2 = 0.712

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0

0.0 1.0 2.0 3.0 4.0 Idle CO %RSD CO %

Truck Idle Test Test and Matchin g Vehicle RSD Emissions (RSD N=57,867)

y = 1.5121x R 2 = 0.7963 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5

0.0 0.5 1.0 1.5 2.0 2.5 3.0 Idle CO %RSD CO %



### Low Speed Idle test to IM240 Projection Passenger HC HC R2 CO CO R2 RSD / Idle 1.1007 0.81 1.3267 0.71 IM240 / RSD 0.0087 0.98 15.947 0.92 IM240 / Idle 0.0096 21.1569 Truck HC HC R2 CO CO R2 RSD / Idle 1.0336 0.92 1.5121 0.8 IM240 / RSD 0.0111 0.98 18.765 0.94 IM240 / Idle 0.0115 28.3746

### 38 

### Figure V-2 RSD vs. 2500 Idle Test Emissions

Table V-2 High Speed Idle to IM240



### Using the ratios derived above, IM240 g/mi equivalent emissi ons were projected for the vehicles tested with the idle test procedure. The low speed idle results were used to estimate emissions reductions as all model year vehicles tested at idle were required to pass the low speed idle test. Model Year Average Truck Idle 2500 Test and Matching Vehicle RSD Emissions (RSD N=57,867)

y = 1.548x R 2 = 0.927 0 100 200 300 400 500 600 700 800 900

0 100 200 300 400 500 600 700 800 Idle HC ppmRSD HC ppm Model Year Average Passenger Idle 2500 Test and Matching Vehicle RSD Emissions (RSD N=8,843)

y = 1.5353x R 2 = 0.8565

0 100 200 300 400 500 600

0 100 200 300 400 500 600 Idle HC ppmRSD HC ppm Model Year Average Passenger Idle 2500 Test and Matching Vehicle RSD Emissions (RSD N=8,843)

y = 1.1789x R 2 = 0.8169
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0

0.0 1.0 2.0 3.0 4.0 Idle CO %RSD CO %

Model Year Average Truck Idle 2500 Test and Matching Vehicle RSD Emissions (RSD N=57,867)

y = 1.4699x R 2 = 0.8185

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 Idle CO %RSD CO %



### 2500 RPM Idle test to IM240 Projection Passenger HC HC R2 CO CO R2 RSD / 2500 1.5353 0.86 1.1789 0.82 IM240 / RSD 0.0087 0.98 15.947 0.92 IM240 / 2500 0.0134 18.7999 Truck HC HC R2 CO CO R2 RSD / 2500 1.548 0.93 1.4699 0.82 IM240 / RSD 0.0111 0.98 18.765 0.94 IM240 / 2500 0.0172 27.5827

### 39 

### Figure V-3 RSD vs. IM240 Test Emissions

Model Year Average Pa ssenger IM240 Test and Matching Vehicle RSD Emissions (RSD N=449,842)

y = 0.0087x R 2 = 0.9812
0.0 0.5 1.0 1.5 2.0 2.5

0 50 100 150 200 250 

### RSD HC ppmIM240 HC g/mi

Model Year Average Pa ssenger IM240 Test and Matching Vehicle RSD Emissions (RSD N=449,842)

y = 15.947x R 2 = 0.9229 0 5 10 15 20 25 30

0.0 0.3 0.5 0.8 1.0 1.3 1.5 

### RSD CO %IM240 CO g/mi

Model Year Average Pa ssenger IM240 Test and Matching Vehicle RSD Emissions (RSD N=449,842)

y = 0.0016x + 0.1754 R 2 = 0.9885
0.0 0.5 1.0 1.5 2.0 2.5

0 250 500 750 1000 1250 1500 

### RSD NO ppmIM240 NOx g/mi Model Year Average Truck IM240 Test and Matching Vehicle RSD Emissions (RSD N=423,746)

y = 0.0111x R 2 = 0.9756

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5

0 50 100 150 200 250 300 350 400 

### RSD HC ppmIM240 HC g/mi

Model Year Average Truck IM240 Test and Matching Vehicle RSD Emissions (RSD N=423,746)

y = 18.765x R 2 = 0.9368

0 10 20 30 40 50 60

0.0 0.5 1.0 1.5 2.0 2.5 3.0 

### RSD CO %IM240 CO g/mi

Model Year Average Truck IM240 Test and Matching Vehicle RSD Emissions (RSD N=423,746)

y = 0.0016x + 0.3013 R 2 = 0.9785

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5

0 500 1000 1500 2000 

### RSD NO ppmIM240 NOx g/mi

### 40 

### B. Annual Mileage Weighting Because of data entry errors and odometer rollo ver on older, high mileage vehicles, obtaining estimates of annual mileage from the I/M Pr ogram odometer readings for each model year and type of vehicle is not recommended. To avoid these problems, annual mileages for vehicles were taken from the 2008 ERG repor t on Colorado mileage accumulation rates 7



### . The estimated annual mileages are shown in Ta ble V-3 for LDGVs and LDGTs. In Table VI3 the mileage accumulation rates for LDGT2, 3 a nd 4 were weighted together to obtain a single LDGT value. This table i ndicates that newer model year ve hicles are driven more miles annually than older vehicles. It also indica tes that 1998 and newer model year LDGTs, which emit greater masses of pollution than LDGVs are driven more miles annually than 1998 and newer model year LDGVs.
`

Table V-3 Estimated Annual Mileage in 2013 Year LDGV LDGT 1983 4,304 4,550 1984 4,304 4,554 1985 4,304 4,562 1986 4,434 4,583 1987 4,481 4,630 1988 4,502 4,668 1989 4,552 4,741 1990 4,780 4,851 1991 5,088 5,019 1992 5,430 5,256 1993 5,672 5,519 1994 6,002 5,824 1995 6,331 6,135 1996 6,653 6,471 1997 6,974 6,940 1998 7,369 7,437 1999 7,764 7,863 2000 8,188 8,345 2001 8,613 8,900 2002 9,032 9,502 2003 9,450 10,087 2004 9,905 10,727 2005 10,360 11,245 2006 10,746 11,817 2007 11,132 12,303 2008 11,870 12,834 2009 12,023 13,215 2010 12,307 13,433 2011 12,357 13,514 2012 11,600 12,428 2013 9,650 8,995

### 41 

### C. Annual Emissions Reductions Annual tons of emissions were projected for vehicle type and model year by multiplying the numbers of vehicles by annual mileage and av erage g/mi emission levels. Results were projected for initial tests and final tests to determ ine the initial and final tons of emissions and, therefore, the tons of reducti on. The results are listed in Appe ndix B for IM240 and Idle tests.
Table V-4 first shows the reductions from the Cl ean Screen audit tests. Based on the audit tests, the second part of the table projects the potential re ductions from the Clean Screen vehicles if all vehicles with redeemed Clean Sc reen notices had been tested at a station. The third part of the table shows the reductions from the vehicles tested at inspection stations, which includes the Clean Screen audit vehicles. The total potential reductions from the program are the combination of the potential reductions from the Clean Screened vehicles plus the actual reductions from th e vehicles tested at stations. In Table IV-4, Clean Screen effectiveness wa s expressed without re ference to the annual vehicle miles traveled (VMT) by each model year of vehicles. The more complete analysis in Table V-4 shows the Clean Screen program effectiveness when the VMT and Gas Cap 4 

### estimates are factored in. During 2013, the Cl ean Screen program retained 97.3%, 96.7% and 97.6% respectively of potential HC, CO and NOx emission reductions in vehicles subject to testing. For vehicles initially tested in calendar year 2013, the I/M Program is projected to have eliminated 559.0 tons of HC, 6,924.4 tons of CO and 414.8 tons of NOx for one year of vehicle travel – based on the IM240 driving cycle. Because the program is biennial, these reductio ns are approximately half of the reductions that would be measured over a full two-year cycle of the program.
The tons of reductions cited here do not relate di rectly to the total mobile emissions inventory. The reductions cited are for tailpipe emissions a nd are in terms of the IM240 driving cycle. State Implementation Plan reductions are based on different driving cycles, are subject to many adjustments for speed, road type, temperat ure, air conditioning loads, etc., and therefore are larger than the IM24 0 measured reductions. As noted earlier, the reductions shown do not include reducti ons from maintenance actions performed on vehicles before their initial in spection. These may be quite substantial, especially for OBD-II vehicles that turn on the ch eck engine light to alert owners to problems.

4 The evaporative emissions have not been adjusted for mileage but the effect of an adjustment would be small. Gas cap

failures are more evenly distributed by age than tailpipe failures and only part of the evaporative emissions are running losses dependent on miles traveled.

### 42 Table V-4 Estimated Annual Tons of Reduction (IM240 and Idle Tested Vehicles

* NOx is not reported for idle tests.



### Table V-4 also shows that, during calenda r year 2013, 233,760 vehicles were exempted through Clean Screen, and 951,115 vehicles received a station test. Ther efore, 19.7% of the 1,184,875 unique vehicles were Clean Screened.
If the fraction of Clean Screen vehicles had be en 30% of vehicles subject to inspection there would have been 355,463 Clean Screens and 829,413 St ation tests. Assuming this increase was achieved by increasing on-road fleet coverage rather than by relaxing the Clean Screen standards, the projected emissions reta ined would have been 95.9%, 94.5% and 95.9% respectively of potentia l HC, CO and NOx tailpipe emission reductions. Audit Vehicle Reductions (IM240 tons/yr)

Audit Tests Unique Vehicles HC CO NOx Enhanced IM240 4,234 0.14 4.33 0.18

Potential from RS Vehicles (IM240 tons/yr)
RapidScreen Unique Vehicles HC CO NOx Enhanced Area 233,760 8.0 239.2 10.1 Gas Cap estimate from Mobile6 7.4

Station Reductions (IM240 tons/yr)

Station I/M Vehicles Unique Vehicles HC CO NOx Enhanced IM240 869,433 368.9 5,133.9 414.8 Enhanced Idle* 81,682 154.2 1,790.5 Gas Cap scaled from MOVES 35.9 951,115 559.0 6,924.4 414.8

Total Potential Reductions 574.4 7,163.6 424.8 RapidScreen Exhaust Impact 1.4% 3.3% 2.4% Rapidscreen Gas Cap Impact 1.3% Retained Reductions 97.3% 96.7% 97.6%

### 43 

## VI. IM240 Projected Emissions by Model Year Figures VI-1 through VI-6 s how the annual emissi ons inventories and reductions by model year and vehicle type for the vehicles tested in 2013 at stations, ba sed on the IM240 driving cycle. The projected exhaust emissions invent ory for the Clean Screen vehicles and Idle tested vehicles are also shown. The biennial testing cycle of the E nhanced area causes the difference between the sizes of the bars for od d model year vehicles vs. even model year vehicles.
Not included in these charts:

 most 2010 and newer models not ye t subject to inspection;

 any estimate of pre-inspection emission reductions;

 NOx emissions for 81,682 vehicles tested w ith the idle test: 1981 and older models 12,891 (16%), 1982 and newer trucks 64,174 (78%), and 1982 & newer passenger vehicles 4,617 (6%). The Figures VI-1 to 6 illustrate that 1995 and older vehicles, which are fewer in number and driven fewer miles each year, still contribute ma ny tons of excess emissions in the I/M area – especially old trucks.

### 44 

### Figure VI-1 LDGV HC Reducti ons and Remaining Emissions

Figure VI-2 LDGT HC Reductions and Remaining Emissions 0 50 100 150 200 250P 1965&olderP 1966-70P 1971-75P 1976-81P 1982P 1983P 1984P 1985P 1986P 1987P 1988P 1989P 1990P 1991P 1992P 1993P 1994P 1995P 1996P 1997P 1998P 1999P 2000P 2001P 2002P 2003P 2004P 2005P 2006P 2007P 2008P 2009P 2010P 2011P 2012P 2013 IM240 Equivalent 

### Exhaust Tons Per Year in 2013 Passenger HC
Idle Reduction HC IM240 Reduction HC Idle Final HC IM240 Final HC Clean Screen Vehicles HC



### 0 50 100 150 200 250T 1965&olderT 1966-70T 1971-75T 1976-81T 1982T 1983T 1984T 1985T 1986T 1987T 1988T 1989T 1990T 1991T 1992T 1993T 1994T 1995T 1996T 1997T 1998T 1999T 2000T 2001T 2002T 2003T 2004T 2005T 2006T 2007T 2008T 2009T 2010T 2011T 2012T 2013 

### IM240 Equivalent Exhaust Tons Per Year in 2013 Light Truck HC
Idle Reduction HC IM240 Reduction HC Idle Final HC IM240 Final HC Clean Screen Vehicles HC

### 45 

### Figure VI-3 LDGV CO Reductions and Remaining Emissions

Figure VI-4 LDGT CO Reductions and Remaining Emissions 0 500 1,000 1,500 2,000 2,500P 1965&olderP 1966-70P 1971-75P 1976-81P 1982P 1983P 1984P 1985P 1986P 1987P 1988P 1989P 1990P 1991P 1992P 1993P 1994P 1995P 1996P 1997P 1998P 1999P 2000P 2001P 2002P 2003P 2004P 2005P 2006P 2007P 2008P 2009P 2010P 2011P 2012P 2013 IM240 Equivalent 

### Exhaust Tons Per Year in 2013 Passenger CO
Idle Reduction CO IM240 Reduction CO Idle Final CO IM240 Final CO Clean Screen Vehicles CO



### 0 500 1,000 1,500 2,000 2,500T 1965&olderT 1966-70T 1971-75T 1976-81T 1982T 1983T 1984T 1985T 1986T 1987T 1988T 1989T 1990T 1991T 1992T 1993T 1994T 1995T 1996T 1997T 1998T 1999T 2000T 2001T 2002T 2003T 2004T 2005T 2006T 2007T 2008T 2009T 2010T 2011T 2012T 2013 

### IM240 Equivalent Exhaust Tons Per Year in 2013 Light Truck CO Idle Reduction CO IM240 Reduction CO Idle Final CO IM240 Final CO Clean Screen Vehicles CO

### 46 

### Figure VI-5 LDGV NOx Reductions and Remaining Emissions

Figure VI-6 LDGT NOx Reductions and Remaining Emissions 0 50 100 150 200 250 300 350 400 450 500P 1965&olderP 1966-70P 1971-75P 1976-81P 1982P 1983P 1984P 1985P 1986P 1987P 1988P 1989P 1990P 1991P 1992P 1993P 1994P 1995P 1996P 1997P 1998P 1999P 2000P 2001P 2002P 2003P 2004P 2005P 2006P 2007P 2008P 2009P 2010P 2011P 2012P 2013 IM240 Equivalent 

### Exhaust Tons Per Year in 2012 Passenger NOx Idle Reduction NOx n/a IM240 Reduction NOx Idle Final NOx n/a IM240 Final NOx Clean Screen Vehicles NOx



### 0 50 100 150 200 250 300 350 400 450 500T 1965&olderT 1966-70T 1971-75T 1976-81T 1982T 1983T 1984T 1985T 1986T 1987T 1988T 1989T 1990T 1991T 1992T 1993T 1994T 1995T 1996T 1997T 1998T 1999T 2000T 2001T 2002T 2003T 2004T 2005T 2006T 2007T 2008T 2009T 2010T 2011T 2012T 2013 

### IM240 Equivalent Exhaust Tons Per Year in 2012 Light Truck NOx
Idle Reduction NOx n/a IM240 Reduction NOx Idle Final NOx n/a IM240 Final NOx Clean Screen Vehicles NOx

### 47 

## VII. RapidScreen Benefits
Rapidscreen provided benefits to vehicle owners of $5.15M through reduced time and expense associated with eliminated inspection station visits. The elimination of station inspections also yielded net savings in gree nhouse gases and 195,600 gall ons of gasoline. This section summarizes the operational costs and benefits of the Rapidscreen program.
A. Greenhouse Gas and Pollutants fr om Clean Screen Operations

The following were considered in deriving the net emissions, greenhouse gas and fuel use associated with the RapidScreen program:

- RSD van operations;

- RSD generators;

- RSD unit calibration and audit gases;

- Reductions from eliminated trips to inspection stations.

Table VII-1 summarizes these amounts.

Table VII-1 Reductions in Greenhouse Gases and Pollutants from RapidScreen Operations



### 1. RapidScreen Operating Vehicles Emissions and fuel usage of RSD vans, audit truc ks and maintenance vehicles associated with the RapidScreen program were developed from the average IM 240 emissions of each vehicle from the most recent inspect ions performed from 2010 through 2013. Idle test emissions were converted to IM240 g/mi using the conve rsion factors described in Section V. Emissions were scaled up to match MOVES es timates of running emissions vs. IM240 using scaling factors of 1.0 for hydro carbons, 1.92 for CO and 2.23 for NO x 

### . Odometer changes were pro-rated to provide annual mileages. Fu el use was calculated using EPA city fuel Activity HC t/y r CO t/yr NOx t/yr CO2 t/y r Fuel gal. RapidScreen Operations RapidScreen operating vehicles (vans, audit trucks, maintenance) 0.132 1.64 0.027 91.1 10,208 Generators 0.943 24.08 0.081 59.4 10,097 Calibration and audit gases 0.005 0.05 0.003 0.5 Total Rapidscreen operations 1.080 25.77 0.111 150.9 20,305

RapidScreen Vehicle Emission Reductions Station trip, waiting & testing 0.445 12.24 2.148 1925.9 215,905

Net benefit (cost) (0.63) (13.53) 2.037 1774.9 195,600

### 48 

### economies for the vehicle models or similar models. CO 2 

### tons were calculat ed at the rate of 8.92 x 10 -3 

### tons per gallon (http://www.epa.gov/cleanen ergy/energy-resources/r efs.html).
2. Generators Typical emissions and CO 2 

### grams over a four minute peri od were obtained by collecting emissions from two generators using lane IM24 0 equipment. Emissions were collected from the generator while another vehicle was dr iven on the dynamometer. Emissions and CO 2 

### grams were then multiplied by 15 to obtain g/ hour and by the Active Collection Van Hours from Table III-1. Fuel gallons were back calculated from CO 2 

### tons. Envirotest is in the process of replacing ex isting generators with newer, lower emitting models that would eliminate 67% of HC em issions and up to 98% of the generator NOx emissions.
3. Calibration and Audit Gases Calibration and Audit Gas emissions were calculated directly from the use estimates presented in Table VII-2. The liters of calibrati on and audit gases at 70F and normal pressure were multiplied by the pollutant concentration percentages and by the pollutant mass per liter to obtain tons.

Table VII-2 Calibration and Audit Gas Emissions



### 4. RapidScreen Vehicle Emissions Reductions The RapidScreen program eliminated the ne ed for 233,760 station insp ections that would otherwise require travel , waiting and inspection. RSD VANS AL Cyls BL Cyls CL Cyls Liters at 70F NP CO % CO2 % HC % NO % HC PPM NOX PPM CO tons CO2 tons HC tons NO tons Calibration 240 30 0 1,028,820 3.00 12.90 0.15 0.15 1500 1500 0.0425 0.2874 0.0033 0.0023 2 Point Audit 80 10 342,940 0.50 14.70 0.04 0.10 400 1000 0.0024 0.1092 0.0003 0.0005 ATP / DOR A 12 0 47,916 0.00 15.05 0.00 0.00 0 0 0.0000 0.0156 0.0000 0.0000 F 12 0 16 61,964 5.00 11.55 0.60 0.03 6000 250 0.0043 0.0155 0.0008 0.0000 G 12 0 47,916 0.20 14.91 0.01 0.15 100 1500 0.0001 0.0155 0.0000 0.0001 H 12 0 47,916 0.30 14.84 0.02 0.10 200 1000 0.0002 0.0154 0.0000 0.0001 J 12 0 16 61,964 0.50 14.70 0.04 0.10 400 1000 0.0004 0.0197 0.0001 0.0001 K 12 0 47,916 1.00 14.34 0.05 0.03 500 300 0.0007 0.0149 0.0001 0.0000 L 12 0 47,916 1.50 13.99 0.07 0.01 700 100 0.0010 0.0145 0.0001 0.0000 Q 12 0 16 61,964 3.00 12.92 0.11 0.05 1100 500 0.0026 0.0173 0.0001 0.0000 Total 416 40 48 1,797,232 0.0541 0.5249 0.0048 0.0031

Capacities and g/l AL Cyls BL Cyls CL Cyls CO % CO2 % HC % NO % Cylinder L @2000psi 29.5 15.7 5.9 Mol. Wt 28 44 44 30 Liters gas at 70F NP 3993 2350 878 g/l 1.3 2.0 2.0 1.3

### 49 

### The average round trip to a station was estimated to be 9.5 miles. For every two minutes a car is idling, it uses about the same amount of fuel it takes to go about one mile according to the Consumer Energy Center (http://www.consumerenergycenter.org/myths/idling.html). This implies the average waiting time of 13.5 minutes was equivalent to 6.8 miles of driving. The equivalent of another equivalent 2.2 miles of driving was spent moving through the inspection lane for a total equivalent of 18.5 miles per insp ection. Eliminated trip/inspection emissions tons were calculated from the inspection mileage multiplied by the average IM240 g/mi emissions of the RapidScreen audit sample and the number of exempted vehicles. As noted above, IM240 emissions were scaled up to match MOVES estimates of running emissions vs. IM240. Gallons of fuel saved were estimated using an average of 20mpg.

B. RapidScreen Vehicle Owner Savings
Table VII-3 quantifies the RapidScr een benefits to vehicle owners . The average round trip to an inspection station was assumed to take an average of 28.5 minutes (9.5 miles at 20mph). Average wait and test times were both 13. 5 minutes. The waiting and testing fuel consumption was estimated to be the equivalent of driving another 8.4 miles. Vehicle owner time was assumed to be worth half the Denver area average hourly wage of $25.05 per hour, or $12.53 per hour. Travel savings from were calculated at the IR S rate of 56.5c per mile per IRS Notice IR-2012- 95, Nov. 21, 2012. Total savings were $5.15M or $22.02 per vehicle.

Table VII-3 RapidScreen Vehicle Owner Savings 

### Activity Vehicles Minutes Hours Unit $ $'M Station round trip @ 20mph 233760 28.5 111036 12.53 $ 1.39 $ Testing 233760 13.5 52479 12.53 $ 0.66 $ Waiting 233760 13.5 52596 12.53 $ 0.66 $ Miles Driving miles equiv. 233760 18.5 0.565 $ 2.44 $ Total vehicle owner savings 5.15 $

### 50 

## VIII. Recommendations
In 2015, several program changes will be implemente d that will affect th e vehicles subject to testing and test procedures:

 New models will be exempt for seven years vs. four years currently;

 Models 8 to 11 years old will be tested by scanning the OBD status with a fallback to IM240 allowed for vehicles with no more than one out of a select group of OBD system monitors not set ready;

 Models over 11 years old will continue to be tailpipe tested using IM240 or Idle. Currently clean screen notices are issued to 30% of subject vehicles due to renew registration. Unless changes are made to clean screen criter ia, the 2015 program changes will act to reduce this percentage in two ways:

 The percentage of vehicles qualifying for clean screen is highest among the newest three model years that will now be exempt and will reduce current clean screens by at least one third;

 If/when the LEI is updated with OBD failure rates for 8 to 11 year old vehicles, the percentage of passing the screen wi ll decrease dramatically. It is desirable to increase clean screen pr oductivity provided the program remains compliant with the clean screen goals modeled using Mobile6. MIL-on rates in Colorado are currently higher than observed in other stat e I/M programs. As owners realize MIL-on is required, Colorado observed MIL-on rates should fall. Modeling using existing MIL-on rates th erefore overstates the impacts of the transition for OBD inspected models. OBD testing of 8-11 year olds will affect fail rates but the extent will depend on the number of pre-inspection repairs ob tained by vehicle owners in response to the new program rules. It is suggested 2015 should be a transitional year . The year will start using the current clean screen criteria with only minor changes such as a potential increase in the existing 2% RSDLEI fail cutpoint. This will be evaluated to determine whether adjusting the threshold, e.g. to 5%, in fall of 2014 for 2015 renewal candidates, could increase motorist convenience and clean screens without materially a ffecting program emission reductions.

In addition:

 Recommended Reg 11 changes:
o Permit periodic adjustments of the LEI fail % cutpoints as approved by CDPHE, e.g. in 2014 for IM240 tested models, and during 2015 for OBD tested models;
o Allow a separate LEI OBD fail % cut point for the OBD tested RSD-LEI models;

### 51 

###  In order to provide emissions data on clean screen OBD tested models in 2015, set registration table flags set to force dual OBD and IM240 inspection of 8-11 year old models selected for clean sc reen audit. The IM240 bei ng either a normal IM240 with fast-pass allowed, or, if operationally accep table, a full IM240. These OBD model vehicles selected as part of the random 2% clean scr een audit sample IM240’s may form part of the independently required 5% OBD-IM240 sample;

 In order to create an adequate audit sa mple by end of June 2015 for a mid-year evaluation, and provided doing so will not mate rially increase wait times, increase the clean screen audit percentage to 3.5% or 4% during the first half of 2015 and reduce it to 0.5% or 0% during the second half year. This will allow appropriate LEI cutpoints to be developed in fall of 2015 for 2016 renewals.

### 52 

# References

1 

### “ 

### The Colorado Remote Sensing Program January – December 2011”, Envirotest report for the Colorado Department of Public Health and Environment, November 2012

2 

### Colorado Air Quality Control Commission, “Re gulation Number 11, Motor Vehicle Emissions Inspection Program”, http://www.cdphe.state .co.us/regulations/a irregs/5CCR1001-13.pdf

3 

### Colorado Department Of Public Health and Envi ronment, Air Pollution Control Division, Mobile Sources Section, “Colorado On-road Vehicle Em issions Remote Sensing System (COVERS) Specifications” Amended July 2010

4 

### Klausmeier R., “Technical Note: Estimating Fu ll IM240 Emissions Based on Fast Pass Emission Results”, November 2005

5 

### Wenzel, T. “Evaluation of Arizona’s Enhanced I/M Program”, Presented at the 9th CRC On-Road Vehicle Emissions Workshop. April 1999.

6 

### McClintock, P. “The Denver Remote Sensing Clean Screening Pilot”, Envirotest report for the Colorado Department of Health and Environment, December 1999.

7 

### “ 

### Colorado Mileage Accumulation Rates from VID Od ometer Readings Draft Report” for CDPHE by Eastern Research Group, Inc. June 30, 2008

### Appendix A1 Colorado 2013 Transient Test Emissions Reductions Unresolved fails remaining in area 33% Model First Last Initial Final Reduction % Year/Type Result Result Vehicles Fail% HC CO NOX HC CO NOX HC CO NOX

1982 Pass - 258 1.62 19.18 2.02 1.62 19.18 2.02 0.0% 0.0% 0.0%

P Fail Pass 59 17.2% 4.56 51.09 2.02 1.52 19.35 1.88 66.6% 62.1% 7.0% Fail Unresolv. 26 7.6% 5.59 85.27 1.92 1.99 29.03 0.65 64.4% 66.0% 66.0% Fail Waiver 1 0.3% 1.49 70.11 0.38 1.49 70.11 0.38 0.0% 0.0% 0.0% Total Fail% 344 25.0% 2.42 29.80 2.00 1.63 20.10 1.88 32.7% 32.5% 6.0%

1983 Pass - 462 1.29 12.26 2.07 1.29 12.26 2.07 0.0% 0.0% 0.0%

P Fail Pass 98 16.0% 2.32 36.51 2.06 1.24 14.85 1.79 46.7% 59.3% 13.2% Fail Unresolv. 49 8.0% 4.46 73.11 1.91 1.56 24.31 0.57 65.1% 66.7% 69.9% Fail Waiver 3 0.5% 4.50 140.30 1.08 4.73 146.55 0.24 -5.0% -4.5% 77.6% Total Fail% 612 24.5% 1.73 21.65 2.05 1.32 14.30 1.89 23.5% 33.9% 7.5%

1984 Pass - 619 1.23 11.35 1.92 1.23 11.35 1.92 0.0% 0.0% 0.0%

P Fail Pass 147 17.3% 2.86 39.51 1.97 1.44 14.26 2.05 49.7% 63.9% -4.4% Fail Unresolv. 79 9.3% 5.47 75.77 1.82 1.73 23.32 0.59 68.4% 69.2% 67.3% Fail Waiver 6 0.7% 5.14 112.15 1.64 4.98 116.14 1.55 3.2% -3.6% 5.9% Total Fail% 851 27.3% 1.94 22.90 1.92 1.34 13.70 1.82 30.7% 40.2% 5.2%

1985 Pass - 1,094 1.05 10.84 1.89 1.05 10.84 1.89 0.0% 0.0% 0.0%

P Fail Pass 226 15.8% 2.21 31.01 2.12 1.09 9.71 1.93 50.7% 68.7% 8.8% Fail Unresolv. 106 7.4% 3.92 58.15 1.79 1.34 19.49 0.58 65.8% 66.5% 67.5% Fail Waiver 2 0.1% 5.59 85.44 1.10 11.43 58.43 1.41 -104.5% 31.6% -27.3% Total Fail% 1,428 23.4% 1.45 17.65 1.92 1.09 11.37 1.80 24.9% 35.6% 6.2%

1986 Pass - 1,228 0.92 7.91 1.80 0.92 7.91 1.80 0.0% 0.0% 0.0%

P Fail Pass 199 13.1% 2.11 25.18 2.17 1.08 9.10 1.89 48.7% 63.9% 13.2% Fail Unresolv. 90 5.9% 5.07 66.22 2.13 1.48 19.40 0.73 70.9% 70.7% 65.7% Fail Waiver 3 0.2% 8.87 78.05 1.85 8.39 69.96 1.92 5.4% 10.4% -4.1% Total Fail% 1,520 19.2% 1.34 13.76 1.87 0.99 8.87 1.75 26.0% 35.5% 6.4%

1987 Pass - 1,974 0.84 7.71 1.81 0.84 7.71 1.81 0.0% 0.0% 0.0%

P Fail Pass 273 11.6% 2.30 26.86 2.08 1.04 9.26 1.72 55.0% 65.5% 17.3% Fail Unresolv. 96 4.1% 4.37 54.71 2.10 1.45 19.04 0.64 66.8% 65.2% 69.5% Fail Waiver 7 0.3% 3.36 49.60 2.75 4.28 55.88 2.81 -27.6% -12.7% -1.9% Total Fail% 2,350 16.0% 1.16 11.98 1.85 0.90 8.49 1.75 22.7% 29.1% 5.5%

1988 Pass - 1,798 0.74 7.84 1.59 0.74 7.84 1.59 0.0% 0.0% 0.0%

P Fail Pass 266 12.3% 2.69 27.10 1.87 0.94 8.74 1.66 65.1% 67.8% 10.9% Fail Unresolv. 91 4.2% 4.34 39.25 2.05 1.37 12.28 0.68 68.4% 68.7% 67.0% Fail Waiver 5 0.2% 4.45 31.72 3.32 4.45 39.36 1.99 0.1% -24.1% 39.9% Total Fail% 2,160 16.8% 1.14 11.59 1.65 0.80 8.21 1.56 29.8% 29.2% 5.2%

1989 Pass - 3,208 0.72 7.90 1.61 0.72 7.90 1.61 0.0% 0.0% 0.0%

P Fail Pass 405 10.8% 2.12 24.65 1.86 0.89 8.60 1.61 58.1% 65.1% 13.4% Fail Unresolv. 131 3.5% 3.84 42.15 2.14 1.16 14.00 0.74 69.8% 66.8% 65.4% Fail Waiver 4 0.1% 4.00 119.43 0.31 4.01 119.56 0.36 -0.1% -0.1% -15.3% Total Fail% 3,748 14.4% 0.99 11.03 1.65 0.76 8.31 1.58 23.0% 24.7% 4.6%

A1-1

### Appendix A1 Colorado 2013 Transient Test Emissions Reductions Unresolved fails remaining in area 33% Model First Last Initial Final Reduction % Year/Type Result Result Vehicles Fail% HC CO NOX HC CO NOX HC CO NOX

1990 Pass - 3,890 0.70 7.69 1.60 0.70 7.69 1.60 0.0% 0.0% 0.0%

P Fail Pass 526 11.4% 1.79 23.38 2.14 0.86 8.23 1.71 52.0% 64.8% 19.9% Fail Unresolv. 176 3.8% 3.52 38.36 2.39 1.13 12.27 0.79 68.0% 68.0% 66.9% Fail Waiver 8 0.2% 4.74 49.18 2.96 1.85 36.29 3.19 60.9% 26.2% -7.8% Total Fail% 4,600 15.4% 0.94 10.73 1.70 0.74 7.98 1.59 21.6% 25.7% 6.5%

1991 Pass - 6,006 0.59 6.73 1.45 0.59 6.73 1.45 0.0% 0.0% 0.0%

P Fail Pass 832 11.7% 1.75 22.18 1.97 0.72 7.04 1.55 59.0% 68.3% 21.7% Fail Unresolv. 273 3.8% 3.16 33.84 2.37 1.02 11.29 0.76 67.6% 66.6% 68.0% Fail Waiver 18 0.3% 3.14 47.36 1.76 3.09 40.87 1.51 1.4% 13.7% 14.3% Total Fail% 7,129 15.8% 0.83 9.67 1.55 0.62 7.02 1.44 24.5% 27.4% 7.3%

1992 Pass - 5,812 0.57 6.25 1.42 0.57 6.25 1.42 0.0% 0.0% 0.0%

P Fail Pass 790 11.5% 1.68 23.39 1.81 0.67 6.52 1.52 59.9% 72.1% 16.2% Fail Unresolv. 256 3.7% 3.66 37.50 2.07 1.23 12.93 0.66 66.3% 65.5% 68.1% Fail Waiver 15 0.2% 4.18 45.81 1.76 2.51 35.38 1.59 39.9% 22.8% 9.6% Total Fail% 6,873 15.4% 0.82 9.47 1.49 0.61 6.60 1.41 25.7% 30.4% 5.8%

1993 Pass - 8,487 0.54 5.76 1.44 0.54 5.76 1.44 0.0% 0.0% 0.0%

P Fail Pass 995 10.1% 1.37 19.52 2.02 0.63 6.23 1.58 54.0% 68.1% 21.6% Fail Unresolv. 330 3.4% 2.76 29.61 2.22 1.00 10.29 0.73 63.7% 65.2% 67.2% Fail Waiver 18 0.2% 2.90 30.61 2.62 4.91 27.55 2.49 -69.3% 10.0% 4.9% Total Fail% 9,830 13.7% 0.71 8.00 1.53 0.57 6.00 1.43 18.5% 25.0% 6.2%

1994 Pass - 9,146 0.42 5.10 1.16 0.42 5.10 1.16 0.0% 0.0% 0.0%

P Fail Pass 961 9.2% 1.50 17.95 1.71 0.52 5.60 1.26 65.0% 68.8% 26.2% Fail Unresolv. 328 3.1% 3.13 29.41 2.19 1.01 9.47 0.72 67.9% 67.8% 67.3% Fail Waiver 11 0.1% 5.19 39.70 2.36 4.78 34.41 2.28 8.0% 13.3% 3.4% Total Fail% 10,446 12.4% 0.61 7.08 1.24 0.45 5.31 1.16 25.6% 25.0% 7.0%

1995 Pass - 14,190 0.40 4.70 1.01 0.40 4.70 1.01 0.0% 0.0% 0.0%

P Fail Pass 1,398 8.7% 1.23 15.74 1.61 0.48 5.10 1.19 60.7% 67.6% 25.7% Fail Unresolv. 443 2.8% 2.38 22.40 2.31 0.78 7.60 0.75 67.2% 66.0% 67.7% Fail Waiver 18 0.1% 1.69 15.15 3.01 1.77 9.66 2.60 -5.1% 36.3% 13.7% Total Fail% 16,049 11.6% 0.53 6.16 1.10 0.42 4.82 1.02 20.7% 21.8% 7.3%

1996 Pass - 12,780 0.31 3.82 0.82 0.31 3.82 0.82 0.0% 0.0% 0.0%

P Fail Pass 1,301 9.0% 0.97 13.35 1.47 0.39 4.48 0.95 59.7% 66.5% 35.2% Fail Unresolv. 309 2.1% 2.41 22.58 2.06 0.78 6.84 0.70 67.7% 69.7% 66.2% Fail Waiver 15 0.1% 1.18 30.39 1.99 1.27 33.86 1.76 -7.6% -11.4% 11.7% Total Fail% 14,405 11.3% 0.42 5.11 0.90 0.33 3.98 0.83 20.9% 22.2% 8.4%

1997 Pass - 19,145 0.30 3.79 0.75 0.30 3.79 0.75 0.0% 0.0% 0.0%

P Fail Pass 1,691 8.0% 0.83 12.81 1.28 0.36 4.43 0.88 57.0% 65.4% 31.1% Fail Unresolv. 391 1.8% 1.93 24.10 2.02 0.66 8.29 0.66 66.0% 65.6% 67.6% Fail Waiver 10 0.0% 2.26 23.14 2.84 4.10 29.06 2.91 -81.5% -25.6% -2.5% Total Fail% 21,237 9.9% 0.37 4.89 0.81 0.31 3.94 0.76 16.2% 19.5% 7.0%

A1-2

### Appendix A1 Colorado 2013 Transient Test Emissions Reductions Unresolved fails remaining in area 33% Model First Last Initial Final Reduction % Year/Type Result Result Vehicles Fail% HC CO NOX HC CO NOX HC CO NOX

1998 Pass - 18,012 0.23 3.41 0.63 0.23 3.41 0.63 0.0% 0.0% 0.0%

P Fail Pass 1,762 8.7% 0.77 12.26 1.18 0.28 3.87 0.70 63.3% 68.5% 40.6% Fail Unresolv. 377 1.9% 1.66 21.08 1.91 0.55 7.23 0.63 66.7% 65.7% 67.1% Fail Waiver 13 0.1% 0.86 12.40 2.00 0.30 6.56 2.07 65.5% 47.1% -3.6% Total Fail% 20,164 10.7% 0.30 4.52 0.70 0.24 3.52 0.64 20.9% 22.0% 9.4%

1999 Pass - 24,969 0.20 2.97 0.57 0.20 2.97 0.57 0.0% 0.0% 0.0%

P Fail Pass 2,307 8.3% 0.64 9.93 1.24 0.24 3.37 0.66 62.5% 66.1% 46.7% Fail Unresolv. 399 1.4% 1.30 17.42 2.08 0.43 6.05 0.70 66.8% 65.3% 66.5% Fail Waiver 9 0.0% 0.75 7.59 2.46 0.79 8.92 2.70 -4.5% -17.5% -9.7% Total Fail% 27,684 9.8% 0.25 3.76 0.65 0.21 3.05 0.58 18.1% 18.9% 10.5%

2000 Pass - 24,217 0.15 2.52 0.46 0.15 2.52 0.46 0.0% 0.0% 0.0%

P Fail Pass 2,120 7.9% 0.58 9.32 1.29 0.21 3.23 0.58 63.9% 65.3% 55.5% Fail Unresolv. 387 1.4% 1.45 16.73 2.20 0.46 5.52 0.72 68.6% 67.0% 67.3% Fail Waiver 15 0.1% 2.13 22.26 2.20 0.62 10.64 2.59 70.7% 52.2% -17.9% Total Fail% 26,739 9.4% 0.20 3.28 0.55 0.16 2.62 0.47 21.8% 19.9% 14.2%

2001 Pass - 29,978 0.10 2.08 0.31 0.10 2.08 0.31 0.0% 0.0% 0.0%

P Fail Pass 1,936 6.0% 0.55 7.65 1.05 0.16 2.63 0.42 70.4% 65.6% 59.7% Fail Unresolv. 256 0.8% 1.21 14.44 2.07 0.38 4.81 0.71 68.3% 66.7% 65.7% Fail Waiver 15 0.0% 2.72 9.24 3.07 0.80 8.45 3.06 70.7% 8.6% 0.5% Total Fail% 32,185 6.9% 0.14 2.52 0.37 0.11 2.14 0.32 22.0% 15.0% 13.1%

2002 Pass - 25,025 0.09 2.42 0.27 0.09 2.42 0.27 0.0% 0.0% 0.0%

P Fail Pass 1,808 6.7% 0.45 7.05 0.88 0.13 2.38 0.37 70.8% 66.3% 58.6% Fail Unresolv. 205 0.8% 1.06 13.39 2.33 0.36 4.11 0.78 65.7% 69.3% 66.5% Fail Waiver 12 0.0% 0.49 9.61 2.63 0.67 8.74 2.51 -36.1% 9.0% 4.9% Total Fail% 27,050 7.5% 0.12 2.82 0.32 0.09 2.43 0.28 21.9% 13.6% 14.3%

2003 Pass - 30,739 0.06 1.34 0.21 0.06 1.34 0.21 0.0% 0.0% 0.0%

P Fail Pass 1,576 4.9% 0.34 5.21 0.78 0.11 2.00 0.31 68.2% 61.6% 60.8% Fail Unresolv. 137 0.4% 1.33 13.03 2.25 0.47 4.78 0.75 65.0% 63.3% 66.8% Fail Waiver 4 0.0% 0.35 12.14 2.46 0.35 6.12 2.18 2.5% 49.6% 11.6% Total Fail% 32,456 5.3% 0.08 1.58 0.24 0.06 1.39 0.22 19.5% 12.1% 12.0%

2004 Pass - 20,421 0.05 1.26 0.15 0.05 1.26 0.15 0.0% 0.0% 0.0%

P Fail Pass 1,172 5.4% 0.33 5.40 0.65 0.10 2.01 0.24 69.6% 62.8% 63.4% Fail Unresolv. 111 0.5% 1.03 12.82 2.31 0.38 3.74 0.76 62.8% 70.8% 67.0% Fail Waiver 6 0.0% 0.92 10.41 3.08 0.80 8.73 2.80 13.2% 16.2% 9.3% Total Fail% 21,710 5.9% 0.07 1.55 0.19 0.06 1.32 0.16 21.8% 14.9% 15.9%

2005 Pass - 30,699 0.04 0.95 0.12 0.04 0.95 0.12 0.0% 0.0% 0.0%

P Fail Pass 1,444 4.5% 0.21 4.00 0.54 0.07 1.36 0.18 67.7% 65.9% 66.9% Fail Unresolv. 73 0.2% 1.56 14.57 1.80 0.44 4.67 0.56 71.7% 68.0% 68.9% Fail Waiver 1 0.0% 0.15 8.57 2.66 0.38 7.40 2.95 -156.2% 13.6% -10.8% Total Fail% 32,217 4.7% 0.05 1.12 0.15 0.04 0.98 0.13 18.4% 12.6% 13.0%

A1-3

### Appendix A1 Colorado 2013 Transient Test Emissions Reductions Unresolved fails remaining in area 33% Model First Last Initial Final Reduction % Year/Type Result Result Vehicles Fail% HC CO NOX HC CO NOX HC CO NOX

2006 Pass - 21,813 0.04 1.12 0.10 0.04 1.12 0.10 0.0% 0.0% 0.0%

P Fail Pass 828 3.6% 0.26 4.99 0.87 0.07 1.48 0.18 73.6% 70.4% 79.7% Fail Unresolv. 46 0.2% 1.60 13.86 2.56 0.49 4.35 0.77 69.4% 68.6% 69.8% Fail Waiver 0 0.0%

------ - - - Total Fail% 22,687 3.9% 0.05 1.29 0.13 0.04 1.14 0.11 19.1% 11.5% 21.4%

2007 Pass - 30,994 0.03 0.92 0.09 0.03 0.92 0.09 0.0% 0.0% 0.0%

P Fail Pass 759 2.4% 0.15 2.69 0.68 0.05 1.27 0.12 66.1% 52.5% 82.8% Fail Unresolv. 27 0.1% 0.88 11.45 2.33 0.28 3.45 0.79 68.4% 69.9% 66.0% Fail Waiver 0 0.0%

------ - - - Total Fail% 31,780 2.5% 0.03 0.97 0.11 0.03 0.93 0.09 8.3% 4.2% 14.1%

2008 Pass - 15,681 0.03 1.00 0.08 0.03 1.00 0.08 0.0% 0.0% 0.0%

P Fail Pass 489 3.0% 0.23 3.40 0.85 0.06 1.39 0.12 75.7% 59.3% 85.6% Fail Unresolv. 17 0.1% 0.92 9.54 2.71 0.30 3.07 0.92 68.0% 67.8% 66.0% Fail Waiver 1 0.0% 0.56 7.45 3.42 0.49 7.89 3.27 11.4% -5.8% 4.6% Total Fail% 16,188 3.1% 0.04 1.08 0.11 0.03 1.02 0.09 15.3% 6.2% 21.6%

2009 Pass - 26,667 0.03 0.95 0.08 0.03 0.95 0.08 0.0% 0.0% 0.0%

P Fail Pass 483 1.8% 0.15 2.36 0.72 0.05 1.33 0.09 67.8% 43.6% 87.1% Fail Unresolv. 15 0.1% 1.36 15.55 3.10 0.46 5.75 0.91 66.4% 63.0% 70.5% Fail Waiver 0 0.0%

------ - - - Total Fail% 27,165 1.8% 0.03 0.98 0.09 0.03 0.96 0.08 7.4% 2.4% 13.1%

2010 Pass - 5,971 0.03 0.96 0.07 0.03 0.96 0.07 0.0% 0.0% 0.0%

P Fail Pass 90 1.5% 0.18 3.42 0.62 0.05 1.28 0.08 71.8% 62.5% 86.6% Fail Unresolv. 9 0.1% 1.46 11.75 1.53 0.40 3.76 0.49 72.9% 68.0% 68.3% Fail Waiver 0 0.0%

------ - - - Total Fail% 6,070 1.6% 0.03 1.01 0.08 0.03 0.97 0.07 11.4% 4.3% 11.5%

2011 Pass - 3,138 0.03 0.99 0.07 0.03 0.99 0.07 0.0% 0.0% 0.0%

P Fail Pass 53 1.7% 0.10 1.64 0.31 0.04 1.23 0.08 54.8% 24.8% 74.6% Fail Unresolv. 8 0.3% 0.14 3.70 0.57 0.05 1.22 0.19 67.0% 67.0% 67.0% Fail Waiver 0 0.0%

------ - - - Total Fail% 3,199 1.9% 0.03 1.00 0.07 0.03 0.99 0.07 3.9% 1.3% 6.6%

2012 Pass - 2,356 0.02 1.01 0.06 0.02 1.01 0.06 0.0% 0.0% 0.0%

P Fail Pass 29 1.2% 0.06 3.51 0.17 0.02 0.83 0.03 75.8% 76.4% 80.1% Fail Unresolv. 4 0.2% 0.03 1.21 0.09 0.01 0.40 0.03 67.0% 67.0% 67.0% Fail Waiver 0 0.0%

------ - - - Total Fail% 2,389 1.4% 0.03 1.04 0.06 0.02 1.01 0.06 2.4% 3.3% 2.9%

2013 Pass - 633 0.02 0.75 0.06 0.02 0.75 0.06 0.0% 0.0% 0.0%

P Fail Pass 3 0.5% 0.01 0.71 0.23 0.02 0.24 0.01 -65.3% 65.8% 93.6% Fail Unresolv. 4 0.6% 0.59 6.58 1.10 0.49 2.20 0.36 18.5% 66.5% 66.7% Fail Waiver 0 0.0%

------ - - - Total Fail% 640 1.1% 0.02 0.79 0.07 0.02 0.76 0.06 2.6% 3.7% 8.6%

2014 Pass - 21 0.03 0.85 0.06 0.03 0.85 0.06 0.0% 0.0% 0.0%

P Fail Pass 0 0.0%

------ - - - Fail Unresolv. 0 0.0%

------ - - - Fail Waiver 0 0.0%

------ - - - Total Fail% 21 0.0% 0.03 0.85 0.06 0.03 0.85 0.06 0.0% 0.0% 0.0%

A1-4

### Appendix A1 Colorado 2013 Transient Test Emissions Reductions Unresolved fails remaining in area 33% Model First Last Initial Final Reduction % Year/Type Result Result Vehicles Fail% HC CO NOX HC CO NOX HC CO NOX Total Passenger Vehicles All Pass - 401,431 0.17 2.51 0.45 0.17 2.51 0.45 0.0% 0.0% 0.0% P Fail Pass 27,026 6.2% 0.84 11.75 1.25 0.33 3.94 0.75 60.9% 66.5% 39.5% Fail Unresolv. 5,249 1.2% 2.42 27.28 2.14 0.79 9.03 0.70 67.1% 66.9% 67.2% Fail Waiver 220 0.1% 2.67 33.53 2.36 2.50 30.24 2.26 6.2% 9.8% 4.3% Total Fail% 433,926 7.5% 0.24 3.40 0.52 0.19 2.69 0.47 21.5% 20.9% 9.3%

A1-5

### Appendix A1 Colorado 2013 Transient Test Emissions Reductions Unresolved fails remaining in area 33% Model First Last Initial Final Reduction % Year/Type Result Result Vehicles Fail% HC CO NOX HC CO NOX HC CO NOX

1982 Pass - 247 2.44 30.88 2.88 2.44 30.88 2.88 0.0% 0.0% 0.0%

T Fail Pass 103 25.9% 4.34 68.97 2.61 2.35 30.83 2.58 45.8% 55.3% 1.2% Fail Unresolv. 46 11.6% 6.88 103.08 2.42 2.10 33.75 0.83 69.5% 67.3% 65.6% Fail Waiver 1 0.3% 3.57 10.40 6.82 1.89 137.67 0.12 46.9% ####### 98.2% Total Fail% 397 37.8% 3.45 49.08 2.76 2.38 31.47 2.56 31.1% 35.9% 7.6%

1983 Pass - 482 2.90 32.87 2.53 2.90 32.87 2.53 0.0% 0.0% 0.0%

T Fail Pass 165 22.9% 4.03 59.42 3.02 2.40 28.71 2.65 40.6% 51.7% 12.3% Fail Unresolv. 71 9.9% 5.48 98.37 2.22 1.78 33.12 0.72 67.6% 66.3% 67.5% Fail Waiver 1 0.1% 2.15 66.24 2.48 2.15 66.24 2.48 0.0% 0.0% 0.0% Total Fail% 719 33.0% 3.41 45.48 2.61 2.67 31.99 2.38 21.7% 29.7% 8.9%

1984 Pass - 603 1.96 24.05 2.65 1.96 24.05 2.65 0.0% 0.0% 0.0%

T Fail Pass 240 24.9% 3.94 58.19 2.68 2.04 24.85 2.75 48.3% 57.3% -2.7% Fail Unresolv. 116 12.0% 6.19 98.68 2.48 1.79 32.53 0.82 71.1% 67.0% 66.8% Fail Waiver 6 0.6% 4.21 39.05 5.43 3.92 39.02 5.49 6.9% 0.1% -1.0% Total Fail% 965 37.5% 2.98 41.60 2.65 1.97 25.36 2.47 33.7% 39.0% 6.8%

1985 Pass - 1,011 1.84 19.25 2.78 1.84 19.25 2.78 0.0% 0.0% 0.0%

T Fail Pass 322 21.7% 3.39 53.69 3.04 1.87 22.16 2.88 44.7% 58.7% 5.4% Fail Unresolv. 144 9.7% 5.67 93.91 2.12 1.85 31.34 0.66 67.3% 66.6% 68.8% Fail Waiver 4 0.3% 7.34 131.13 1.03 3.68 94.91 0.68 49.9% 27.6% 34.2% Total Fail% 1,481 31.7% 2.56 34.30 2.77 1.85 21.27 2.59 27.7% 38.0% 6.4%

1986 Pass - 1,127 1.64 16.23 2.55 1.64 16.23 2.55 0.0% 0.0% 0.0%

T Fail Pass 355 21.8% 3.26 45.75 2.83 1.78 18.18 2.79 45.3% 60.3% 1.7% Fail Unresolv. 136 8.4% 6.06 89.08 2.28 1.89 28.87 0.78 68.8% 67.6% 65.8% Fail Waiver 7 0.4% 4.41 82.89 2.29 3.25 82.94 2.60 26.3% -0.1% -13.7% Total Fail% 1,625 30.6% 2.37 29.07 2.59 1.70 18.01 2.45 28.5% 38.1% 5.2%

1987 Pass - 1,865 1.49 14.20 2.41 1.49 14.20 2.41 0.0% 0.0% 0.0%

T Fail Pass 405 16.8% 2.86 35.71 2.70 1.47 13.51 2.52 48.4% 62.2% 6.8% Fail Unresolv. 138 5.7% 4.75 67.54 2.45 1.40 22.80 0.80 70.5% 66.2% 67.3% Fail Waiver 8 0.3% 4.18 73.16 3.05 3.27 71.94 2.68 21.7% 1.7% 12.0% Total Fail% 2,416 22.8% 1.92 21.05 2.46 1.49 14.77 2.33 22.2% 29.8% 5.1%

1988 Pass - 1,990 1.34 12.12 2.25 1.34 12.12 2.25 0.0% 0.0% 0.0%

T Fail Pass 429 16.7% 2.63 30.85 2.78 1.37 12.50 2.25 48.0% 59.5% 19.0% Fail Unresolv. 144 5.6% 5.17 54.41 2.91 1.69 17.71 0.96 67.4% 67.4% 67.2% Fail Waiver 5 0.2% 5.75 102.88 0.92 4.93 97.83 0.62 14.2% 4.9% 32.5% Total Fail% 2,568 22.5% 1.78 17.79 2.38 1.37 12.66 2.18 23.0% 28.8% 8.4%

1989 Pass - 3,146 1.24 12.48 2.13 1.24 12.48 2.13 0.0% 0.0% 0.0%

T Fail Pass 610 15.4% 2.77 31.58 2.75 1.32 11.99 2.37 52.5% 62.0% 13.9% Fail Unresolv. 186 4.7% 5.00 55.35 2.95 1.57 17.62 0.98 68.5% 68.2% 66.8% Fail Waiver 11 0.3% 4.32 60.42 3.42 4.26 62.47 3.57 1.3% -3.4% -4.2% Total Fail% 3,953 20.4% 1.66 17.58 2.27 1.27 12.79 2.12 23.2% 27.3% 6.7%

A1-6

### Appendix A1 Colorado 2013 Transient Test Emissions Reductions Unresolved fails remaining in area 33% Model First Last Initial Final Reduction % Year/Type Result Result Vehicles Fail% HC CO NOX HC CO NOX HC CO NOX

1990 Pass - 2,587 1.22 11.73 2.21 1.22 11.73 2.21 0.0% 0.0% 0.0%

T Fail Pass 561 17.0% 2.91 33.43 2.66 1.32 11.87 2.30 54.8% 64.5% 13.6% Fail Unresolv. 137 4.2% 5.17 48.25 2.97 1.61 15.99 0.96 68.8% 66.9% 67.6% Fail Waiver 9 0.3% 5.27 43.78 3.24 3.03 32.88 2.72 42.5% 24.9% 16.1% Total Fail% 3,294 21.5% 1.68 17.03 2.32 1.26 11.99 2.17 25.3% 29.6% 6.3%

1991 Pass - 4,396 1.01 11.35 1.91 1.01 11.35 1.91 0.0% 0.0% 0.0%

T Fail Pass 771 14.4% 2.19 26.67 2.64 1.10 10.49 2.09 49.9% 60.7% 20.8% Fail Unresolv. 168 3.1% 3.98 47.34 2.96 1.53 15.89 0.98 61.4% 66.4% 66.8% Fail Waiver 8 0.1% 3.02 36.74 4.75 3.34 34.74 3.54 -10.4% 5.5% 25.5% Total Fail% 5,343 17.7% 1.28 14.73 2.05 1.04 11.41 1.91 18.3% 22.6% 7.0%

1992 Pass - 3,999 1.04 11.07 1.95 1.04 11.07 1.95 0.0% 0.0% 0.0%

T Fail Pass 738 15.0% 2.32 24.54 2.63 1.15 11.10 2.12 50.5% 54.8% 19.4% Fail Unresolv. 173 3.5% 4.78 45.77 3.00 1.38 14.67 0.98 71.1% 68.0% 67.3% Fail Waiver 7 0.1% 3.38 36.17 2.06 4.50 45.47 1.92 -33.1% -25.7% 6.7% Total Fail% 4,917 18.7% 1.37 14.35 2.09 1.08 11.25 1.94 21.5% 21.6% 7.1%

1993 Pass - 7,277 1.01 10.52 2.08 1.01 10.52 2.08 0.0% 0.0% 0.0%

T Fail Pass 1,108 12.8% 2.45 24.76 2.98 1.12 10.54 2.10 54.0% 57.4% 29.4% Fail Unresolv. 249 2.9% 4.17 36.68 3.29 1.35 12.33 1.09 67.7% 66.4% 66.8% Fail Waiver 13 0.2% 3.51 24.19 4.86 3.06 24.65 3.86 13.0% -1.9% 20.6% Total Fail% 8,647 15.8% 1.29 13.12 2.23 1.04 10.60 2.05 19.5% 19.2% 7.9%

1994 Pass - 8,368 0.78 8.74 1.80 0.78 8.74 1.80 0.0% 0.0% 0.0%

T Fail Pass 1,494 14.6% 1.99 21.24 2.73 0.87 9.12 1.89 56.1% 57.1% 30.7% Fail Unresolv. 376 3.7% 3.86 38.24 3.19 1.26 11.98 1.07 67.5% 68.7% 66.5% Fail Waiver 14 0.1% 2.62 23.34 3.88 1.84 22.04 3.81 29.7% 5.6% 1.8% Total Fail% 10,252 18.4% 1.07 11.66 1.99 0.81 8.93 1.79 24.2% 23.4% 10.1%

1995 Pass - 11,703 0.73 8.53 1.79 0.73 8.53 1.79 0.0% 0.0% 0.0%

T Fail Pass 1,987 14.0% 1.92 20.98 2.88 0.83 8.58 1.86 56.6% 59.1% 35.3% Fail Unresolv. 501 3.5% 3.32 29.87 3.70 1.08 9.66 1.22 67.6% 67.7% 67.1% Fail Waiver 29 0.2% 4.24 30.42 2.66 3.26 26.07 2.74 23.1% 14.3% -3.1% Total Fail% 14,220 17.7% 1.00 11.07 2.01 0.76 8.61 1.78 23.4% 22.2% 11.4%

1996 Pass - 10,587 0.42 5.41 1.37 0.42 5.41 1.37 0.0% 0.0% 0.0%

T Fail Pass 1,576 12.6% 1.03 13.86 2.28 0.45 5.71 1.51 56.2% 58.8% 33.7% Fail Unresolv. 292 2.3% 2.58 26.11 3.22 0.87 8.98 1.04 66.3% 65.6% 67.6% Fail Waiver 15 0.1% 3.07 36.78 2.97 1.94 25.26 3.08 36.8% 31.3% -3.7% Total Fail% 12,470 15.1% 0.55 7.00 1.53 0.44 5.56 1.38 20.7% 20.6% 9.7%

1997 Pass - 17,878 0.36 5.13 1.26 0.36 5.13 1.26 0.0% 0.0% 0.0%

T Fail Pass 2,593 12.4% 0.94 13.06 2.19 0.41 5.57 1.38 55.9% 57.4% 37.3% Fail Unresolv. 434 2.1% 2.24 21.21 3.55 0.70 6.89 1.16 68.9% 67.5% 67.5% Fail Waiver 22 0.1% 1.70 24.08 3.51 1.49 20.97 3.27 12.5% 12.9% 6.7% Total Fail% 20,927 14.6% 0.48 6.47 1.42 0.38 5.24 1.27 20.5% 19.0% 10.6%

A1-7

### Appendix A1 Colorado 2013 Transient Test Emissions Reductions Unresolved fails remaining in area 33% Model First Last Initial Final Reduction % Year/Type Result Result Vehicles Fail% HC CO NOX HC CO NOX HC CO NOX

1998 Pass - 17,654 0.32 4.53 1.11 0.32 4.53 1.11 0.0% 0.0% 0.0%

T Fail Pass 2,432 11.8% 0.89 12.62 2.12 0.38 4.98 1.27 57.9% 60.5% 40.0% Fail Unresolv. 461 2.2% 1.92 22.04 3.22 0.64 6.97 1.05 66.9% 68.4% 67.4% Fail Waiver 18 0.1% 1.11 18.94 3.15 1.05 17.76 3.21 5.9% 6.2% -1.9% Total Fail% 20,565 14.2% 0.42 5.90 1.28 0.33 4.65 1.13 21.2% 21.1% 11.7%

1999 Pass - 25,874 0.24 3.45 0.81 0.24 3.45 0.81 0.0% 0.0% 0.0%

T Fail Pass 3,088 10.5% 0.70 10.58 1.84 0.30 3.88 1.00 57.3% 63.3% 45.7% Fail Unresolv. 527 1.8% 1.51 18.26 2.78 0.49 6.11 0.93 67.7% 66.6% 66.7% Fail Waiver 28 0.1% 1.46 26.61 2.80 0.87 11.94 2.80 40.0% 55.1% 0.1% Total Fail% 29,517 12.3% 0.31 4.48 0.95 0.25 3.55 0.83 19.8% 20.8% 12.8%

2000 Pass - 22,666 0.21 3.04 0.70 0.21 3.04 0.70 0.0% 0.0% 0.0%

T Fail Pass 2,390 9.4% 0.58 9.64 1.54 0.26 3.72 0.89 54.7% 61.4% 42.1% Fail Unresolv. 322 1.3% 1.99 23.04 2.63 0.59 8.00 0.87 70.0% 65.3% 66.8% Fail Waiver 15 0.1% 1.14 17.08 3.48 1.56 17.63 3.24 -37.0% -3.2% 7.0% Total Fail% 25,393 10.7% 0.27 3.93 0.80 0.22 3.18 0.72 17.7% 19.1% 10.4%

2001 Pass - 29,019 0.14 2.61 0.47 0.14 2.61 0.47 0.0% 0.0% 0.0%

T Fail Pass 2,370 7.5% 0.42 8.31 1.14 0.19 3.20 0.63 54.8% 61.5% 45.0% Fail Unresolv. 182 0.6% 1.93 21.89 2.85 0.67 8.34 0.91 65.4% 61.9% 68.1% Fail Waiver 13 0.0% 0.94 15.88 3.35 1.39 11.77 3.72 -47.5% 25.9% -11.2% Total Fail% 31,584 8.1% 0.17 3.16 0.54 0.15 2.69 0.49 14.2% 14.7% 9.2%

2002 Pass - 23,316 0.11 2.81 0.42 0.11 2.81 0.42 0.0% 0.0% 0.0%

T Fail Pass 1,740 6.9% 0.39 9.38 1.10 0.17 3.13 0.60 56.0% 66.7% 45.2% Fail Unresolv. 163 0.6% 1.53 26.31 2.57 0.52 8.64 0.83 66.2% 67.2% 67.7% Fail Waiver 15 0.1% 0.95 15.60 2.86 0.90 14.11 2.61 5.9% 9.5% 8.7% Total Fail% 25,234 7.6% 0.14 3.43 0.48 0.12 2.88 0.44 15.1% 15.9% 9.5%

2003 Pass - 31,096 0.09 1.66 0.31 0.09 1.66 0.31 0.0% 0.0% 0.0%

T Fail Pass 1,774 5.4% 0.34 7.40 0.77 0.13 2.60 0.43 61.6% 64.8% 43.8% Fail Unresolv. 89 0.3% 2.02 24.68 2.44 0.59 8.21 0.82 70.7% 66.7% 66.3% Fail Waiver 5 0.0% 2.36 60.00 2.74 1.63 28.55 4.12 30.8% 52.4% -50.4% Total Fail% 32,964 5.7% 0.11 2.04 0.34 0.09 1.73 0.32 14.2% 15.1% 6.5%

2004 Pass - 23,967 0.06 1.42 0.18 0.06 1.42 0.18 0.0% 0.0% 0.0%

T Fail Pass 1,378 5.4% 0.28 6.45 0.63 0.11 2.43 0.28 62.6% 62.3% 54.7% Fail Unresolv. 71 0.3% 0.84 15.58 2.56 0.28 5.19 0.84 66.3% 66.7% 67.0% Fail Waiver 1 0.0% 0.02 0.33 2.74 0.01 0.77 2.05 28.9% -131.1% 25.0% Total Fail% 25,417 5.7% 0.08 1.73 0.21 0.07 1.48 0.19 14.3% 14.3% 11.0%

2005 Pass - 35,394 0.05 1.06 0.12 0.05 1.06 0.12 0.0% 0.0% 0.0%

T Fail Pass 1,266 3.4% 0.21 3.70 0.46 0.09 1.85 0.21 59.5% 49.9% 54.8% Fail Unresolv. 48 0.1% 0.80 11.81 1.90 0.27 3.80 0.66 66.4% 67.8% 65.4% Fail Waiver 7 0.0% 0.81 10.55 2.79 0.73 18.26 2.54 10.0% -73.0% 9.1% Total Fail% 36,715 3.6% 0.06 1.17 0.14 0.06 1.10 0.13 8.3% 6.2% 7.6%

A1-8

### Appendix A1 Colorado 2013 Transient Test Emissions Reductions Unresolved fails remaining in area 33% Model First Last Initial Final Reduction % Year/Type Result Result Vehicles Fail% HC CO NOX HC CO NOX HC CO NOX

2006 Pass - 23,116 0.04 1.03 0.11 0.04 1.03 0.11 0.0% 0.0% 0.0%

T Fail Pass 935 3.9% 0.15 2.78 0.53 0.07 1.39 0.18 52.9% 49.9% 66.6% Fail Unresolv. 32 0.1% 1.01 20.90 2.94 0.38 7.25 1.00 62.7% 65.3% 65.9% Fail Waiver 0 0.0%

------ - - - Total Fail% 24,083 4.0% 0.05 1.12 0.13 0.05 1.05 0.11 7.8% 6.4% 12.6%

2007 Pass - 35,304 0.03 0.85 0.09 0.03 0.85 0.09 0.0% 0.0% 0.0%

T Fail Pass 1,272 3.5% 0.09 2.37 0.26 0.04 1.36 0.11 55.4% 42.7% 59.9% Fail Unresolv. 10 0.0% 0.59 7.81 2.75 0.20 2.58 0.91 67.0% 67.0% 67.0% Fail Waiver 0 0.0%

------ - - - Total Fail% 36,586 3.5% 0.04 0.91 0.10 0.03 0.87 0.09 5.4% 4.0% 6.2%

2008 Pass - 18,094 0.03 0.90 0.09 0.03 0.90 0.09 0.0% 0.0% 0.0%

T Fail Pass 745 4.0% 0.09 2.41 0.20 0.04 1.65 0.08 51.4% 31.6% 60.2% Fail Unresolv. 12 0.1% 0.38 15.52 0.96 0.13 5.21 0.33 65.3% 66.4% 65.9% Fail Waiver 0 0.0%

------ - - - Total Fail% 18,851 4.0% 0.03 0.97 0.09 0.03 0.93 0.08 5.9% 3.8% 5.8%

2009 Pass - 23,024 0.03 0.82 0.08 0.03 0.82 0.08 0.0% 0.0% 0.0%

T Fail Pass 655 2.8% 0.03 1.08 0.15 0.03 1.12 0.06 12.7% -3.8% 60.9% Fail Unresolv. 6 0.0% 0.56 4.79 0.84 0.18 1.58 0.28 67.0% 67.0% 67.0% Fail Waiver 0 0.0%

------ - - - Total Fail% 23,685 2.8% 0.03 0.83 0.08 0.03 0.83 0.07 0.7% 0.0% 3.4%

2010 Pass - 6,327 0.03 0.77 0.07 0.03 0.77 0.07 0.0% 0.0% 0.0%

T Fail Pass 147 2.3% 0.06 2.25 0.07 0.02 0.95 0.05 59.7% 57.9% 21.3% Fail Unresolv. 4 0.1% 0.56 6.18 1.61 0.19 2.04 0.53 67.0% 67.0% 67.0% Fail Waiver 0 0.0%

------ - - - Total Fail% 6,478 2.3% 0.03 0.81 0.07 0.03 0.78 0.07 3.6% 4.0% 1.5%

2011 Pass - 2,239 0.03 0.84 0.06 0.03 0.84 0.06 0.0% 0.0% 0.0%

T Fail Pass 54 2.3% 0.04 1.82 0.17 0.02 1.16 0.08 33.8% 36.1% 53.0% Fail Unresolv. 5 0.2% 0.06 2.30 0.20 0.02 0.76 0.07 67.0% 67.0% 67.0% Fail Waiver 0 0.0%

------ - - - Total Fail% 2,298 2.6% 0.03 0.86 0.06 0.03 0.85 0.06 1.3% 2.2% 4.0%

2012 Pass - 1,302 0.03 0.77 0.05 0.03 0.77 0.05 0.0% 0.0% 0.0%

T Fail Pass 13 1.0% 0.04 0.74 0.06 0.02 0.63 0.06 53.0% 14.8% -9.8% Fail Unresolv. 0 0.0%

------ - - - Fail Waiver 0 0.0%

------ - - - Total Fail% 1,315 1.0% 0.03 0.77 0.05 0.03 0.77 0.05 0.7% 0.1% -0.1%

2013 Pass - 594 0.03 0.70 0.05 0.03 0.70 0.05 0.0% 0.0% 0.0%

T Fail Pass 3 0.5% 0.02 0.65 0.04 0.01 0.71 0.02 65.5% -9.4% 42.8% Fail Unresolv. 1 0.2% 0.47 8.07 2.35 0.16 2.66 0.78 67.0% 67.0% 67.0% Fail Waiver 0 0.0%

------ - - - Total Fail% 598 0.7% 0.03 0.72 0.05 0.03 0.71 0.05 2.0% 1.2% 5.1%

2014 Pass - 30 0.02 0.52 0.05 0.02 0.52 0.05 0.0% 0.0% 0.0%

T Fail Pass 0 0.0%

------ - - - Fail Unresolv. 0 0.0%

------ - - - Fail Waiver 0 0.0%

------ - - - Total Fail% 30 0.0% 0.02 0.52 0.05 0.02 0.52 0.05 0.0% 0.0% 0.0%

A1-9

### Appendix A1 Colorado 2013 Transient Test Emissions Reductions Unresolved fails remaining in area 33% Model First Last Initial Final Reduction % Year/Type Result Result Vehicles Fail% HC CO NOX HC CO NOX HC CO NOX Total Trucks All Pass - 396,282 0.24 3.25 0.61 0.24 3.25 0.61 0.0% 0.0% 0.0% T Fail Pass 33,719 7.7% 1.06 14.33 1.73 0.49 5.81 1.15 53.6% 59.5% 33.6% Fail Unresolv. 5,244 1.2% 3.19 37.07 2.98 1.02 12.22 0.98 68.0% 67.0% 67.1% Fail Waiver 262 0.1% 2.70 33.90 3.19 2.22 29.85 3.06 17.7% 11.9% 4.3% Total Fail% 435,507 9.0% 0.34 4.54 0.73 0.27 3.57 0.66 20.8% 21.2% 9.5%

Fleet Total All Pass - 797,713 0.20 2.88 0.53 0.20 2.88 0.53 0.0% 0.0% 0.0% All Fail Pass 60,745 7.0% 0.96 13.18 1.51 0.42 4.98 0.97 56.4% 62.2% 35.8% Fail Unresolv. 10,493 1.2% 2.80 32.17 2.56 0.91 10.62 0.84 67.6% 67.0% 67.1% Fail Waiver 482 0.1% 2.68 33.74 2.81 2.35 30.03 2.69 12.5% 11.0% 4.3% Total Fail% 869,433 8.2% 0.29 3.97 0.62 0.23 3.13 0.56 21.1% 21.1% 9.4%

A1-10

### Appendix B Colorado 2013 Enhanced IM240 Test Reduction Tons Initial Tons/Yr Final Tons/Yr Reduction Tons/Yr
Type Annual Miles Unique Vehicles HC CO NOx HC CO NOx HC CO NOx P 1982 4,304 344 4.0 48.6 3.3 2.7 32.8 3.1 1.3 15.8 0.2 P 1983 4,304 612 5.0 62.9 5.9 3.8 41.5 5.5 1.2 21.3 0.4 P 1984 4,304 851 7.8 92.5 7.7 5.4 55.3 7.3 2.4 37.2 0.4 P 1985 4,304 1,428 9.8 119.6 13.0 7.4 77.0 12.2 2.4 42.5 0.8 P 1986 4,434 1,520 10.0 102.3 13.9 7.4 65.9 13.0 2.6 36.3 0.9 P 1987 4,481 2,350 13.5 139.0 21.5 10.4 98.6 20.3 3.1 40.4 1.2 P 1988 4,502 2,160 12.2 124.2 17.7 8.6 88.0 16.8 3.7 36.2 0.9 P 1989 4,552 3,748 18.5 207.4 31.1 14.3 156.3 29.7 4.3 51.1 1.4 P 1990 4,780 4,600 22.8 260.1 41.2 17.8 193.4 38.5 4.9 66.7 2.7 P 1991 5,088 7,129 33.1 386.7 61.9 25.0 280.8 57.4 8.1 105.8 4.5 P 1992 5,430 6,873 33.6 389.7 61.4 25.0 271.4 57.8 8.6 118.4 3.6 P 1993 5,672 9,830 43.4 491.5 93.9 35.3 368.6 88.1 8.0 122.8 5.8 P 1994 6,002 10,446 42.2 489.4 85.9 31.4 367.2 79.8 10.8 122.2 6.1 P 1995 6,331 16,049 59.0 690.4 122.8 46.8 540.1 113.9 12.2 150.3 8.9 P 1996 6,653 14,405 44.0 540.2 95.5 34.8 420.3 87.5 9.2 119.9 8.0 P 1997 6,974 21,237 60.3 798.6 132.9 50.5 642.5 123.6 9.8 156.1 9.3 P 1998 7,369 20,164 49.9 740.5 115.1 39.5 577.3 104.3 10.4 163.2 10.8 P 1999 7,764 27,684 59.7 890.6 154.1 48.8 722.4 138.0 10.8 168.2 16.1 P 2000 8,188 26,739 49.4 790.6 132.4 38.7 633.4 113.6 10.8 157.2 18.9 P 2001 8,613 32,185 42.7 769.7 112.5 33.3 653.9 97.7 9.4 115.8 14.8 P 2002 9,032 27,050 32.7 758.8 87.3 25.5 655.6 74.8 7.2 103.2 12.5 P 2003 9,450 32,456 26.1 534.8 82.8 21.0 470.0 72.9 5.1 64.8 10.0 P 2004 9,905 21,710 17.1 366.5 45.1 13.4 312.0 37.9 3.7 54.5 7.2 P 2005 10,360 32,217 17.6 411.3 53.5 14.4 359.6 46.5 3.2 51.7 7.0 P 2006 10,746 22,687 13.1 345.9 36.1 10.6 306.3 28.4 2.5 39.6 7.7 P 2007 11,132 31,780 13.3 380.1 41.0 12.2 364.3 35.2 1.1 15.8 5.8 P 2008 11,870 16,188 8.2 229.5 23.4 7.0 215.1 18.3 1.3 14.3 5.0 P 2009 12,023 27,165 11.4 353.5 33.7 10.5 345.0 29.3 0.8 8.5 4.4 P 2010 12,307 6,070 2.5 83.1 6.9 2.3 79.6 6.1 0.3 3.6 0.8 P 2011 12,357 3,199 1.2 43.7 3.2 1.2 43.2 3.0 0.0 0.6 0.2 P 2012 11,600 2,389 0.8 31.7 1.8 0.7 30.7 1.8 0.0 1.0 0.1 P 2013 9,650 640 0.2 5.4 0.4 0.2 5.2 0.4 0.0 0.2 0.0 P Total 433,905 765.1 11678.8 1739.0 605.8 9473.3 1562.7 159.3 2205.5 176.3 T 1982 4,550 397 6.9 97.7 5.5 4.7 62.7 5.1 2.1 35.1 0.4 T 1983 4,550 719 12.3 164.0 9.4 9.6 115.4 8.6 2.7 48.6 0.8 T 1984 4,554 965 14.4 201.5 12.8 9.6 122.8 12.0 4.9 78.7 0.9 T 1985 4,562 1,481 19.1 255.5 20.6 13.8 158.4 19.3 5.3 97.1 1.3 T 1986 4,583 1,625 19.5 238.6 21.2 13.9 147.8 20.1 5.6 90.8 1.1 T 1987 4,630 2,416 23.6 259.6 30.3 18.4 182.1 28.8 5.3 77.5 1.6 T 1988 4,668 2,568 23.5 235.1 31.4 18.1 167.3 28.8 5.4 67.8 2.6 T 1989 4,741 3,953 34.3 363.2 46.9 26.3 264.2 43.8 8.0 99.0 3.1 T 1990 4,851 3,294 29.6 300.0 40.9 22.1 211.2 38.3 7.5 88.8 2.6 T 1991 5,019 5,343 37.8 435.5 60.7 30.8 337.2 56.5 6.9 98.3 4.2 T 1992 5,256 4,917 39.0 408.8 59.6 30.6 320.5 55.4 8.4 88.3 4.2 T 1993 5,519 8,647 67.8 690.1 117.4 54.6 557.4 108.0 13.2 132.7 9.3 T 1994 5,824 10,252 70.6 767.4 130.7 53.6 587.7 117.6 17.1 179.7 13.2 T 1995 6,135 14,220 95.7 1064.3 193. 3 73.3 828.3 171.3 22.4 236.0 22.0 T 1996 6,471 12,470 49.3 622.9 136.0 39.1 494.3 122.8 10.2 128.5 13.2 T 1997 6,940 20,927 76.1 1035.3 227. 8 60.6 838.6 203.5 15.6 196.7 24.2 T 1998 7,437 20,565 71.5 993.9 215.3 56.4 784.5 190.2 15.2 209.4 25.1 T 1999 7,863 29,517 78.8 1146.5 243. 4 63.2 908.0 212.4 15.6 238.5 31.1 T 2000 8,345 25,393 62.4 916.9 187.8 51.3 742.2 168.3 11.0 174.7 19.5 T 2001 8,900 31,584 53.4 977.7 166.7 45.8 834.2 151.3 7.6 143.6 15.4 T 2002 9,502 25,234 37.9 905.6 127.3 32.2 761.2 115.2 5.7 144.4 12.1 T 2003 10,087 32,964 39.3 747.8 124.8 33.7 635.1 116.6 5.6 112.7 8.2 T 2004 10,727 25,417 23.2 520.0 63.9 19.9 445.8 56.9 3.3 74.2 7.0 T 2005 11,245 36,715 27.6 531.7 62.7 25.3 498.6 57.9 2.3 33.1 4.7 T 2006 11,817 24,083 15.4 352.6 40.5 14.2 330.1 35.4 1.2 22.6 5.1 T 2007 12,303 36,586 17.8 450.0 47.4 16.8 431.8 44.4 1.0 18.2 3.0 T 2008 12,834 18,851 9.2 258.9 24.1 8.6 249.1 22.7 0.5 9.8 1.4 T 2009 13,215 23,685 9.7 286.7 26.8 9.6 286.8 25.9 0.1 -0.1 0.9 T 2010 13,433 6,478 2.7 77.5 6.6 2.6 74.4 6.5 0.1 3.1 0.1 T 2011 13,514 2,298 1.0 29.6 2.0 1.0 28.9 2.0 0.0 0.6 0.1 T 2012 12,428 1,315 0.5 13.8 1.0 0.5 13.8 1.0 0.0 0.0 0.0 T 2013 8,995 598 0.2 4.2 0.3 0.2 4.2 0.3 0.0 0.1 0.0 T Total 435,477 1070.3 15352.9 2485.0 860.7 12424.6 2246.6 209.6 2928.4 238.4 Total 869,382 1835.4 27031.8 4224.0 1466.5 21897.9 3809.3 368.9 5133.9 414.8
B-120% 19% 

### Appendix B - Colorado 2011 RapidScreen Audit IM 240 Test Reduction Tons
Initial Tons/Yr Final Tons/Yr Reduction Tons/Yr

Type Annual Miles Unique Vehicles HC CO NOx HC CO NOx HC CO NOx P 1982 4,304 - 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 P 1983 4,304 - 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 P 1984 4,304 - 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 P 1985 4,304 1 0.0 0.1 0.0 0.0 0.1 0.0 0.0 0.0 0.0 P 1986 4,434 2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 P 1987 4,481 2 0.0 0.1 0.0 0.0 0.1 0.0 0.0 0.0 0.0 P 1988 4,502 - 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 P 1989 4,552 4 0.0 0.1 0.0 0.0 0.1 0.0 0.0 0.0 0.0 P 1990 4,780 2 0.0 0.1 0.0 0.0 0.1 0.0 0.0 0.0 0.0 P 1991 5,088 4 0.0 0.1 0.0 0.0 0.1 0.0 0.0 0.0 0.0 P 1992 5,430 6 0.0 0.2 0.0 0.0 0.2 0.0 0.0 0.0 0.0 P 1993 5,672 5 0.0 0.1 0.0 0.0 0.1 0.0 0.0 0.0 0.0 P 1994 6,002 9 0.0 0.3 0.1 0.0 0.3 0.1 0.0 0.0 0.0 P 1995 6,331 27 0.1 0.7 0.2 0.1 0.7 0.2 0.0 0.0 0.0 P 1996 6,653 21 0.0 0.6 0.1 0.0 0.6 0.1 0.0 0.0 0.0 P 1997 6,974 54 0.1 1.3 0.3 0.1 1.3 0.3 0.0 0.0 0.0 P 1998 7,369 49 0.1 1.8 0.3 0.1 1.3 0.2 0.0 0.5 0.0 P 1999 7,764 80 0.2 2.1 0.4 0.2 2.1 0.4 0.0 0.1 0.0 P 2000 8,188 76 0.1 1.6 0.3 0.1 1.6 0.3 0.0 0.0 0.0 P 2001 8,613 141 0.1 2.6 0.4 0.1 2.6 0.4 0.0 0.0 0.0 P 2002 9,032 132 0.1 4.4 0.4 0.1 3.0 0.4 0.0 1.4 0.0 P 2003 9,450 206 0.1 3.0 0.5 0.1 3.0 0.5 0.0 0.0 0.0 P 2004 9,905 114 0.1 1.5 0.2 0.1 1.5 0.2 0.0 0.0 0.0 P 2005 10,360 246 0.1 2.6 0.3 0.1 2.5 0.3 0.0 0.2 0.0 P 2006 10,746 127 0.0 1.4 0.1 0.0 1.4 0.1 0.0 0.0 0.0 P 2007 11,132 278 0.1 3.1 0.3 0.1 3.1 0.3 0.0 0.0 0.0 P 2008 11,870 61 0.0 0.7 0.1 0.0 0.7 0.1 0.0 0.0 0.0 P 2009 12,023 152 0.1 1.9 0.2 0.1 1.8 0.2 0.0 0.0 0.0 P 2010 12,307 - 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 P Total 1,799 1.5 30.4 4.1 1.4 28.3 4.1 0.1 2.1 0.0 T 1982 4,550 - 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 T 1983 4,550 - 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 T 1984 4,554 - 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 T 1985 4,562 - 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 T 1986 4,583 - 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 T 1987 4,630 1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 T 1988 4,668 - 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 T 1989 4,741 3 0.0 0.2 0.0 0.0 0.2 0.0 0.0 0.0 0.0 T 1990 4,851 1 0.0 0.1 0.0 0.0 0.1 0.0 0.0 0.0 0.0 T 1991 5,019 2 0.0 0.2 0.0 0.0 0.2 0.0 0.0 0.0 0.0 T 1992 5,256 4 0.0 0.3 0.0 0.0 0.3 0.0 0.0 0.0 0.0 T 1993 5,519 3 0.0 0.2 0.0 0.0 0.2 0.0 0.0 0.0 0.0 T 1994 5,824 4 0.0 0.3 0.0 0.0 0.2 0.0 0.0 0.1 0.0 T 1995 6,135 5 0.0 0.3 0.0 0.0 0.3 0.0 0.0 0.0 0.0 T 1996 6,471 19 0.1 1.1 0.1 0.1 0.8 0.1 0.0 0.3 0.0 T 1997 6,940 39 0.1 1.7 0.4 0.1 1.6 0.4 0.0 0.0 0.1 T 1998 7,437 59 0.2 2.1 0.5 0.2 2.0 0.5 0.0 0.1 0.0 T 1999 7,863 101 0.2 3.0 0.7 0.2 2.7 0.6 0.0 0.3 0.0 T 2000 8,345 86 0.1 2.0 0.5 0.1 2.0 0.5 0.0 0.0 0.0 T 2001 8,900 195 0.3 4.5 0.9 0.3 4.4 0.9 0.0 0.1 0.0 T 2002 9,502 135 0.2 3.9 0.6 0.1 3.1 0.6 0.0 0.7 0.0 T 2003 10,087 270 0.2 4.8 0.9 0.2 4.7 0.9 0.0 0.1 0.0 T 2004 10,727 181 0.1 2.7 0.4 0.1 2.8 0.4 0.0 -0.2 0.0 T 2005 11,245 419 0.3 6.0 0.7 0.3 5.8 0.7 0.0 0.2 0.0 T 2006 11,817 192 0.1 2.5 0.2 0.1 2.5 0.2 0.0 0.0 0.0 T 2007 12,303 459 0.2 5.7 0.6 0.2 5.1 0.6 0.0 0.6 0.0 T 2008 12,834 78 0.0 0.9 0.1 0.0 1.0 0.1 0.0 0.0 0.0 T 2009 13,215 179 0.1 2.3 0.2 0.1 2.4 0.2 0.0 0.0 0.0 T 2010 13,433 - 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 T Total 2,435 2.3 44.7 7.2 2.2 42.4 7.1 0.1 2.2 0.2 Total 4,234 3.8 75.1 11.3 3.6 70.8 11.2 0.1 4.3 0.2

B-2