P.1 

OAR Box 1830 

Prepped by Ollie Stewart 

Document Number: 

27) IV-B-23 

Docket Number: 

A-87-11 

Printed 11/13/2008 7:20:52 AM Sheet 2 7 of 232 
____________ _ P.2 

3 May, 1993 

Attached three documents which were originally witheld from FOIA 

RIN 6938-91 under the deliberative process exemption, but were later 

released: 

29. EPA Staff Assessment: Evaluation of NHTSA's July 

1991 Report "An Assessment of the Safety of Onboard 

Refueling Vaopr Recovery Systems." 15 pages. 

09/23/91. 

30. Brief Summary of evap/onboard fire safety issues. 

12 pages. 07/22/91. 

42. Brief Summary of evap/onboard fire safety issues. 

12 pages. 07/22/91. 
P.3 

24 

EPA STAFF ASSESSMENT 

9/23/91 

Evaluation of NHTSA's July 1991 Report 

"An Assessment of the Safety of Onboard 

Refueling Vapor Recovery System*" 

I. Introduction 

jIn July 1991, the National Highway Traffic Safety 

Administration (NHTSA) released a study entitled, "An Assessment of 

the Safety of Onboard Refueling Vapor Recovery Systems." The study 

concluded that onboard systems would result in an increase in 

safety risk and thus have a negative impact on motor vehicle 

safety. This document evaluates the NHTSA study. It consists of 

a discussion of NHTSA's stated objectives and the implication of 

these objectives with respect to producing a definitive finding on 

safety (Section II), a summary and analysis of key NHTSA findings 

(Section III), and finally, a brief discussion of overall 

conclusions (Section IV) . 

II. Study Objectives and Definitive Finding 

Aa in the previous study of onboard system safety performed 

for NHTSA by Arthur D. Little (ADL), this report lackamthe*^ 

substance from which a determination concerning the safety issue 

can be made. The stated purpose of the report identifies why the 

report is foundationally deficient in its assessment of safety 

risk. NHTSA states on page 2: 

"While many factors entered the assessment, the principal 

issues addressed were: 

o Compared to the risk of injury in current motor vehicles, 

would an ORVR system increase safety risk? 

o Is the assessment of ORVR safety based upon an evaluation 

of systems which are developed to the point they are 

capable of mass production in motor vehicles? That is, 

is there uncertainty concerning ORVR system design and 

operation, and hence even greater concerns about CRVR 

safety?" 

o Are other alternatives available to achieve the objective 

of refueling vapor control and, if so, what are their 

safety risks compared to ORVR?" 

The first guestion indicates that NHTSA's assessment focused 

on establishing whether onboard systems increase motor vehicle 
P.4 

r\ 

safety risk. Characterization of the magnitude of any potential 

safety risks was not a goal of the NHTSA study. Instead NHTSA 

focused on describing the failure modes from which an increase in 

risk is possible. This, however does not go far enough. To simply 

list the problems that may occur in a system is inconsistent with 

good engineering practice. Without an estimation of a failure 

mode's probability of occurrence, an evaluation of its the 

consequences, and some consideration of potential remedies, it is 

impossible to make useful conclusions about safety risk because 

failure modes with extremely small probabilities or consequences 

cannot be considered grounds for deciding that a potential risk is 

unreasonable. 

The second question refers to prototype development of onboard 

systems. NHTSA states that uncertainty concerning ORVR system 

design and operation in prototype vehicles would result in greater 

concerns about ORVR systems. It is beyond reason to suggest that 

manufacturers must have fully developed systems capable of mass 

production before a rule requiring onboard systems has been 

finalized. If such a line of reasoning is taken to its logical 

conclusion, all future automotive technologies pose unacceptable 

safety risks because, currently, there is uncertainty concerning 

prototype development of all future technologies. 

NHTSA's treatment of the prototype issue as one of the 

principal onboard safety concerns implies that NHTSA believes that 

manufacturers are having a lot of trouble designing workable 

onboard systems. This misplaced emphasis makes it difficult to 

regard.the-study as ar_ unbiased- assessment of the safety. iiiuaig^-

associated with onboard refueling vapor recovery systems. 

The third question's relevancy is predicated on NHTSA's 

apparent position that anv increase in safety risk from onboard 

systems is an unreasonable risk if a safe alternative control 

technology (such as Stage II controls) is available. This may be 

a passable argument in the context of Section 202(a)(4) of the 

Clean Air Act, which directs EPA to consider alternative 

technologies in evaluating safety. On the other hand, it would 

hardly seem reasonable to allow an unquantified, possibly minute, 

increase in safety risk to force the disregard of the Clean Air 

Act's mandate for onboard controls. NHTSA's pre-occupation with 

this approach also takes away from the primary purpose of their 

study—the assessment of the safety of onboard systems. 

Furthermore, the report assumes that Stage II controls are the only 

alternative to canister-based onboard technology, failing to even 

mention bladder and diaphragm technologies. The Stage II vs 

onboard issue is discussed in more detail in Section III below. 
P.5 

III. Summary and Analysis of NHTSA Safety Issues 

A. Summary of NHTSA Safety Issues 

The essential points of the safety concerns described in the 

Findings and Conclusions section of the NHTSA report are: 

1. There are no ORVR prototypes which satisfy all 

performance and safety criteria. 

2. ORVR systems will be much more complex than current 

evaporative systems. 

3. Vapor could be released from lines and connections during 

refueling and cause a fire. The vapor flow rate will be 

much larger than in current evaporative systems. Testing 

shows a flame 2-3 feet in length is possible. 

4. in use experience shows increase in fire risk from 

evaporative controls. 

5. Testing indicates that current evaporative canisters can 

lose their integrity and result in significant selfsustaining fires in the presence of an ignition source. 

ORVR systems will store much more vapor in canisters than 

current evaporative systems. 

6. Stage II is a safe alternative — therefore any increase 

in onboard safety risk is unreasonable. 2.:*r«". 
P.6 

3. Analysis of NHTSA Safety Issues 

I• Lack of Prototype Vehicles 

In October 1990 and April 1991, NHTSA sent information 

requests to the major U.S. and .foreign auto manufacturers, asking 

for information on a variety of issues related to onboard, 

including ORVR system prototype development, test results, vapor 

flow rates, etc. NHTSA's primary conclusion based on the 

information supplied by the manufacturers and on prototype testing 

conducted in the past is: 

NHTSA Concern: 

NHTSA states on page 23: "There are no ORVR prototypes that 

can function satisfactorily under all operating conditions and 

can meet current evaporative and tailpipe emission 

requirements. Further, no manufacturer, the API, nor EPA has 

reported on a single vehicle that has been fitted with an ORVR 

system, of any design, to a vehicle that will meet the more 

stringent tailpipe and enhanced evaporative emissions 

requirements of the 1990 Clean Air Act Amendments." 

Analysis 

• Promising prototypes exist: NHTSA's statement that "there are 

no ORVR prototypes that can function satisfactorily" is untrue 

in that it implies that they know that all existing prototypes 

will fail; in actuality promising prototypes do e.imisimmWox^ 

example, the EPA Vehicle Based Simple System (VBSS) prototype 

might have passed tests in high ambient temperature conditions 

had those tests been conducted. NHTSA's survey of the 

manufacturers showed that a large number of prototypes have 

been built, including 56 by General Motors alone. It seems 

unlikely that a corporation with the engineering expertise of 

GM would have continued development if all attempts were 

unsuccessful. Finally, although NHTSA's survey of 

manufacturers turned up 3 manufacturers with prototypes which 

have passed the FMVSS 301 test, NHTSA failed to note this as 

a positive sign that safe onboard designs are possible. 

• Faulty logic: The above statement appears to imply that there 

is cause for safety concern because manufacturers have not 

developed ORVR prototypes which have been proven to satisfy 

all current and planned performance and safety criteria. This 

reasoning is faulty in several respects. First, there is no 

auto industry incentive to perfect prototypes for the purpose 

of a regulatory decision, nor would one expect that 

information on successful prototypes would be released. 

Second, fully operational prototypes cannot be expected to 

exist before a rule is finalized. Third, the other emissions 
P.7 

systems referred to above (enhanced evaporative and tighter 

tailpipe controls) have not been fully developed; thus it 

would be difficult for an onboard prototype to pass standards 

for these systems, and indeed, few vehicles of any sort have 

done so. Additionally, Congress provided four years leadtime 

to develop fully functional systems, as was requested by some 

manufacturers. The fact that all tests have not been 

conducted cannot be used to conclude that manufacturers are 

incapable of developing prototypes that can function 

satisfactorily. In fact, in relation to their required 

implementation date, onboard systems are farther along in 

their development than most other new systems. 

• | Discussion of prototype testing misleading: NHTSA stated: "In 

all cases that have been reported where vehicles were tested 

in high ambient temperatures, the vehicles experienced fuel 

spitback, premature nozzle shutoff, fuel expulsion, and liquid 

fuel entering the canister." However, on the next page, NHTSA 

discusses two charts that "summarize all ORVR testing that 

NHTSA is aware of through July of 1991," remarking that: "It 

1 is noteworthy that almost no tests are recorded on the chart 

for high ambient temperature testing." 

• Well-known relevant material is neglected: Section VI of the 

NHTSA Study includes over a page of very negative discussion 

on the 1987 Buick LeSabre outfitted with an onboard system by 

API. API's improved design, presented in SAE paper #900155 

and claimed by the paper's authors to resolve the problems 

raised by NHTSA, is not even mentioned. Furthermore^ NHTSA 

dismisses the essentially flawless performance of the EPA 

vehicle by pointing to the lack of high temperature testing as 

a shortcoming. 

2. Complexity 

Complexity has been a major issue with onboard system safety 

since release of the August 1987 NPRM. It is a particularly 

difficult issue to address because it broadly encompasses the 

entire design of onboard systems. Not surprisingly, concerns 

arising from complexity have been numerous, including possible 

increased incidence of crash fires due to greater numbers of 

components and connections and increased chance of failure during 

operation due to design defects, tampering, improper maintenance, 

and manufacturing error. 

NHTSA Concern: 

Regarding crash situations NHTSA states on page 29: "Based on 

the results of all testing and evaluation conducted to date, 

production ORVR systems will be much more complex than current 

evaporative systems. This increased complexity leads to the 
P.8 

following safety concerns: 

The increase in the number of parts and connections will 

make ORVR systems more vulnerable to failure in 

collisions and normal use. 

Some ORVR components, such as filler pipe nozzle sealing 

devices and vapor vent valves, will need to be placed in 

areas of potential collision damage, adding to the 

likelihood of fuel and vapor release in collisions. 

These sealing devices and valves are necessary, since 

testing has shown that simpler systems cannot perform 

adequately. 

Many ORVR components will be larger and therefore more 

difficult to locate in areas less likely to sustain 

damage in collisions..." 

Regarding non-crash situations, NHTSA states on page 8: 

"Because the ORVR system has more components, there is 

1 increased opportunity for failure, which can increase safety 

risk due to design and manufacturing errors, tampering and 

poor maintenance." 

Analysis: 

Much work has been done on the complexity issue in the past. 

NHTSA introduces nothing new on this issue and in fact neglects 

some important points and past results: •••-*?-*-.>.•*.-, 

D A assessment: EPA's "Summary and Analysis of Comments 

Regarding the Potential Safety Implications of Onboard Vapor 

Recovery Systems" (August 1988) indicated no increased safety 

risk due to complexity in various evaporative system designs. 

NHTSA failed to address this analysis. 

Battelle study: The Battelle study of the complexity issue, 

based on a failure modes and effects analysis, found that 

there was little difference in overall risk between onboard 

control equipped vehicles and current vehicles. Although the 

analysis did not consider all operational situations, such as 

purge, this report is still of value. Battelle successfully 

answered ADL's criticisms of Battelle's analysis in a report 

completed under contract with API. NHTSA fails to even 

acknowledge Battelle's work. If NHTSA disagrees with the 

work, reasons should be given. 

Complexity does not necessarily lead to increased risk: In 

its report prepared for NHTSA in June 1989, even ADL conceded 

that "increased complexity does tend to increase risks, but 

does not have to increase risk and can in fact reduce risk.'' 
P.9 

Degree of complexity unknown: Because production vehicles have 

not been built, there is still some question as to how complex 

production systems will actually be. EPA has shown with its 

Vehicle Based Simple System prototype program that simpler 

systems are at least possible. 

Experience with vapor control systems: Past experience with 

evaporative systems, as well as the consultation with NHTSA, 

has helped to identify many of the possible failure modes 

associated with onboard systems. In a response to a NHTSA's 

questions about the safety of ORVR systems, Toyota's response 

iwas: "In regard to the safety problems of ORVR, we will give 

our cooperation to NHTSA. It is, however, very difficult to 

show the risks of our system concretely or quantitatively. 

Frankly, if certain safety risks appear concretely, our 

experienced engineers can then modify the design to eliminate 

the problem." 

Exaggerated statements concerning complexity: NHTSA stated 

that "sealing devices and valves are necessary, since testing 

has shown that simpler systems cannot perform adequately." 

This is flatly untrue. Although some systems have performed 

poorly, there are promising prototypes which use a simple 

system. The testing has not shown that the EPA prototype 

performs poorly. Also, NHTSA states that "many ORVR 

components will be larger and therefore more difficult to 

locate". The canister is the only component that will be more 

difficult to locate due to increased size. 

Leadtime: If there is any question about complexity being a 

safety issue, the automakers have four years to develop and 

test their systems in cooperation wi^h NHTSA to ensure system 

safety and integrity. NHTSA made no mention of this in the 

study. 

Remedies: NHTSA's analysis ignores the fact that concerns 

about risks related to complexity can be largely resolved 

through either engineering solutions or FMVSS design or test 

standards. 

3. Vapor Release Purine Refueling 

NHTSA Concern: 

NHTSA states on page 29: "During the refueling process, vapor 

flow from the fuel tank to the ORVR canister for vapor storage 

can be 45 to 65 grams per minute. This is much higher than 

evaporative flow rates, which rarely exceed 6 to 8 grams per 

minute and are generally less than 1 gram per minute. Should 

this vapor escape, due to a design or manufacturing error, 
P.10 

improper maintenance, or tampering, uncontrolled vapor would 

flow into the engine compartment or under the vehicle and 

ignite, should an ignition source be present." 

Analysis 

Design solutions: Onboard systems can be designed such that 

the canister is located in the rear of the vehicle. Several 

manufacturers have designs which do so. Canisters can also be 

attached to the fuel tank itself, as was demonstrated in an 

API prototype vehicle. In such designs, the refueling vapor 

line to the canister would be relatively short or possibly 

eliminated, confining the flow of vapor to a short distance 

and away from ignition sources. In addition, proper materials 

choices for canisters, vapor lines, and connectors could help 

to minimize potential problems. These approaches would 

minimize tampering, loss of integrity, improper maintenance, 

etc. NHTSA does not mention the possibility of design 

solutions. 

Service station fire risk reduced: Presently, vapors escape 

uncontrolled in direct proximity to the pump operator. Should 

an operator be smoking, fire could result. Onboard systems 

would provide the same benefit in reducing these fires-that 

NHTSA attributes to Stage II. Furthermore, onboard systems 

would control this refueling vapor, not just in nonattainment 

areas as would Stage II, but nationwide. Oddly, NHTSA appears^' 

to treat the escape of refueling vapors as it currently occurs 

(without control) as an acceptable event while it treats 

escape of the same vapors from a leaking onboard system as 

; unacceptable. 

Flow rates misleading: In contrast to evaporative vapor flow, 

the higher flow rates associated with onboard controls (45 -

65 grams/min) are only experienced during the refueling event, 

which is a very small percentage of total driving time. 

Lack of ignition sources: High onboard system vapor flows 

occur only during refueling, when the vehicle is parked, so 

that the only likely ignition source for a leaking onboard 

vapor line would be a hot exhaust system. The Fire Protection 

Handbook published by the National Fire Protection Association 

states that "a hot exhaust pipe seldom ignites a flammable 

mixture even though the surface temperature may be 

considerably above the ignition temperature." In fact, in the 

lab report included as Appendix III of the study, NHTSA states 

that they had problems igniting the flowing vapors using a 

standard hot plate, so they switched to a modified heating 

coil. They make no mention of this in the body of the report, 

instead implying that the heating coil rather than the hot 

8 
P.11 

plate is one of the "ignition sources characteristic of the 

motor vehicle environment." (page 10 of the study). 

Nothing proven: The jets of burning gasoline vapor created in 

the NHTSA tests provide an impressive demonstration. However, 

the lack of correlation between the test conditions and in use 

conditions negates the value of this demonstration. It proves 

that jets of gasoline vapor will burn when ignited. 

Evaporative System Fire Risk 

NHTSA Concern: 

NHTSA states on page 15: "On the basis of assessing real world 

accident data, there is an association of fire risk with 

evaporative control system. That is, the risk of fire 

increases when vehicles are equipped with evaporative systems. 

This finding complements the results of laboratory testing 

described in the previous section, which indicated the 

increased fire risk of evaporative systems." 

Analysis: 

Because no fully developed onboard systems were available for 

evaluation, and "since onboard systems will contain components 

similar to existing evaporative systems,• NHTSA decided to^pexform*^' 

a statistical analysis of historical fire rates associated with the 

introduction of evaporative systems into vehicles. This analysis 

resulted in a finding that evaporative equipped vehicles 

experienced a "statistically significant increase of 27 percent" in 

crash report fire rates compared to pre-evaporative equipped 

vehicles. Ninety-five percent confidence limits were placed at 6 

and 53 percent. 

• Evidence of actual canister fires is scarce: In the past 20 

years, experience indicates that evaporative canisters have 

performed safely in-use. NHTSA has no record of serious 

injury or death occurring from canister fires in crash or noncrash situations. Manufacturers indicated in their responses 

to NHTSA's request for information that they know of very few 

canister related fires. 

• No action taken with existing evaporative controls: A 27 

percent increase in fires due to evaporative controls is a 

very dramatic finding. The summary report contained in 

Appendix IV implies that many lives could be saved each year 

if steps were taken to reduce evaporative system fire hazards. 

It would be difficult to justify any claims that the very 

limited evaporative system-related recalls to date have solved 
P.12 

this problem. The fact that NHTSA has not taken such steps 

immediately is indicative of the lack of confidence NHTSA 

places in the analysis. 

NHTSA admits analysis limited: NHTSA's own statements in the 

report regarding the limitations of this analysis include 

discussion of: (1) the lack of information in crash reports 

establishing a causal link to evaporative systems, (2) the use 

of only 3 model-years of data, (3) the age of the vehicles 

involved, and (4) the low confidence interval of the estimated 

increase in risk. 

Other Limitations: In addition to the limitations discussed 

by NHTSA in its report, one could point out that: (1) it 

involves only crashes of fairly old cars, mostly 9 to 15 years 

of age, and therefore introduces the likelihood of more 

vehicle-specific irregularities in the data, and (2) it came 

from only 4 states. One of the reasons given for neglecting 

;some states' data was "state file not available at NHTSA", 

despite the fact that past evaluations on this issue have used 

readily-accessible data from 14 different states. 

Conclusions drawn despite numerous limitations: It is odd 

that the analysis report itself, provided as an appendix, does 

not mention any limitations in the data used in the analysis. 

Despite its misgivings, NHTSA does not refute any of the 

methodology or findings of the analysis. Instead thesefindings are used as a basis for the negative conclusions 

drawn-on onboard system safety. It is very likely thairthe 27^* 

percent increase is a product of the statistical method used 

rather than the data. A plot of relevant data, including that 

used by NHTSA, exhibits no such trend, as shown in the 

accompanying figure. 

Recall descriptions inconsistent: Every month, NHTSA releases 

a consumer advisory which contains a list of auto safety 

recalls. These advisories identify the make and model of the 

vehicle or equipment involved, with a brief description of the 

safety problem. In some cases, the description provided in 

the monthly consumer advisory is suspiciously different than 

the description provided in Appendix I of the NHTSA safety 

report, which lists manufacturer's safety defect recalls 

involving "emissions control systems components" or resulting 

"from the effects of the evaporative emissions control system 

on vehicle performance." For example, under NHTSA campaign 

number 89V054, the consumer advisory describes the defect as 

follows: 

"Description of Defect: Close proximity of certain hoses 

to high heat emitted from the catalytic converter would 

cause the hose to deteriorate. 

10 
V3 

P.13 

Fire Rates in Passenger Car Crashes 

by State and Vehicle Model Year (1982-87 data) 

-_J

 om

o 

< 

o o 

O 

5

 M-RYLAND 

4 -

V3 

-. 

_ _

3 

1) 

."5 2 

__ 

> 

AYERACE 

M_CHIOAN~^ 

mmi -

I9M 1969 1970 1971 

Vehicle Model Year 

1972 1973 

Firs Rates* In Passenger Car Crashes by Stats and Vehlcis Model Year** 

MODEL 

YEAR 

1968 

1969 

1970 

1971 

1972 

1973 

pre-avg 

post-avg 

% change 

OHIO 

6.21 

5.31 

5.17 

5.46 

- 5.60 

5.17 

5.56 

5.41 

-2.7 

MARYLAND MICHIGAN 

4.95 

6.80 

5.13 

4.78 

4.64 

4.54 

2.89 

3.30 

3.38 

3.92 

3.59 

3.34 

5.63 j 3.19 

4.651 3.62 

-17.3 13.4 

ILLINOIS 

1.44 

1.35 

1.25 

1.30 

0.97 

1.35 

1.35 

1.21 

-10.4 

INDIANA 

1.28 

1.57 

2.19 

1.72 

1.65 

1.30 

1.68 

1.56 

-7.3 

AVERAGE 

3.35 

3.66 

3.42 

3.44 

3.29 

3.14 

3.48 

3.29 

•5.5 

'Fires/1000 Passenger Cars in Accidents 

"1982-87 Data from NHTSA Report "Motor Vehicle Fires in Traffic Crashes and the 

Effects of the Fuel System Integrity Standard" November 1990 (DOT HS 807 675) 

Data from NHTSA Table 2-2 found on p. 2-11 
P.14 

Consequence of Defect: This could result in a sudden loss 

of power, creating the possibility of a rear end crash. 

Corrective Action: Install a heat shield over the 

catalytic converter to protect the hoses from heat 

deterioration." 

On the other hand, the summary of NHTSA campaign number 8 9V054 

provided in the NHTSA report describes the defect in the 

following manner: 

"During operation in high ambient temperatures, when 

large quantities of evaporative emissions were burned in 

the exhaust system, the catalytic converter overheated 

causing vehicle fires. A large heat shield was installed 

to protect hoses in the area." 

Other NHTSA recall campaigns are described similarly in the 

NHTSA report (see recalls 89V106, 88V090, 88V100, 87V040, 

87V155, and 83V108) . 

Canister Fires in Laboratory Testing 

NHTSA Concern: 

NHTSA states on page 10: "At vapor levels of 50 percent 

saturation and above (levels routinely expected), a canister 

which looses its integrity, such as in a crash, will result in 

a significant fire when exposed .to an ignition source 

representative of the motor vehicle operating environment." 

NHTSA also states on page 10: "ORVR canisters, which will 

receive much higher vapor flow rates and total vapor mass than 

existing evaporative systems, would result in an increased 

safety risk compared to existing evaporative canisters." 

Analysis; 

Teeter were not representative of in-use conditions: The 

majority of NHTSA's tests involved highly saturated canisters. 

Production systems are sized according to the working 

capacity, roughly 50 percent of saturation capacity. If 

NHTSA's goal was to test at canister loading levels routinely 

:expected, as implied, it used the wrong range of canister 

loadings. In fact, the limited testing done at loadings more 

typical of properly designed canisters appears to indicate 

that fires would not occur. 

Many vehicle components burn if ignited: It is no surprise 

12 
P.15 

; that the tests show that fire will occur if a loaded canister 

i is broken or melted open and ignited. Tests involving other 

vehicle components constructed of combustible materials would 

show similar fires. The proximity of ignition sources and the 

likelihood of events is the more pertinent question. It i3 

notable that the testing showed no fires caused by the 

!pendulum impact itself, thus refuting claims that evaporative 

and onboard canisters are "firebombs". 

• Canisters can be placed in secure locations: Many 

manufacturers have indicated that canisters would be placed in 

the rear of the vehicle, such as near the fuel tank. In this 

1 location canisters would be better protected from crash 

impact. 

• |Stronger or substitute materials can be used: If canister 

' integrity is really a concern, manufacturers can construct 

them of stronger materials to resist loss of integrity or use 

;some type of mesh to reduce spillage of canister contents in 

the event of rupture. Preformed carbon matrix materials can 

be used instead of granulated forms to eliminate spillage. 

• Lack of supporting material: Appendix III is the complete lab 

report for the canister fire testing discussed in Section IV 

of the NHTSA report. The report lacks the information one 

would normally expect in a lab report to allow duplication of 

the tests. It also contains some serious discrepancies in theinformation that it does provide. For example, test 31 

required 120.4 grams of vapor to saturate the test cs-tjattex^ 

Test 34A, using the same canister at almost the same initial 

weight, needed only 90.3 grams to reach saturation. No 

explanation is given. 

6. Staoe II As a Safe Alternative 

NHTSA Concern: 

NHTSA states on page 27: "Because of the uncertainty 

associated with ORVR safety and information which suggests 

safety concerns exist with these systems, it is impossible to 

quantify the absolute magnitude of the increase in safety risk 

associated with ORVR systems." 

They also contend, "However, by contrasting the potential 

safety risks of ORVR against the safety risks of other 

alternatives to achieve the same objective of ORVR systems, it 

is possible to make a more informed conclusion concerning ORVR 

safety." 

NHTSA presents Stage II as such an alternative, stating on 

page 28: "Implementation of Stage II would negate the need for 

13 
P.16 

ORVR systems, since the objective of capturing refueling 

vapors would be accomplished." 

Analysis: 

ORVR systems safety is th*.consultation issue: A great amount 

of effort has been expended by NHTSA attempting to compare the 

safety of onboard systems to that of Stage II. A more 

relevant comparison is the safety of a refueling event 

involving a conventional vehicle vs that of an onboard 

equipped vehicle. 

Other viable technologies ignored: NHTSA's approach assumes 

that a finding of increased risk from onboard systems, 

combined with a finding of no or decreased risk from Stage II, 

provides a basis for negating the Clean Air Act mandate for 

onboard controls. However, NHTSA only examines canister-based 

onboard technology in its study, ignoring bladder and 

diaphragm technologies. 

ORVR systems provide added benefits nationwide: Stage II 

controls, in preventing the escape of most of the refueling 

vapor, can reduce the risk of service station fire. The 

December 1988 Battelle study, "Service Station Refueling Risk 

Assessment," supports this, pointing out that California may 

account for just 3.5% of all public service station fires in 

which gasoline is identified as the type of material ignited. 

Considering that 10.9% of all gasoline consumption occurs 

there-, it appears that California's Stage II program may*%e*at*^ 

least partially responsible for reducing the incidence of 

service station fires. However, onboard systems would provide 

this benefit to an even greater extent (even if controls were 

limited to light duty vehicles), considering that federal 

Stage II controls would not apply outside of the nonattainment 

areas and would also not apply to the many exempted service 

stations in the nonattainment areas. Maximizing the reduction 

of air toxics would also favor onboard controls. The study 

credits Stage II for this safety risk reduction but makes no 

mention of the very obvious onboard benefit in this regard. 

14 
P.17 

IV. Conclusions 

The NHTSA safety study is not a definitive finding on the 

safety of onboard refueling vapor recovery systems. It does not 

provide enough information on a single major finding to conclude 

that onboard systems will pose an unreasonable risk to motor 

vehicle safety. 

NHTSA states on page 3 of their report that "It would be 

desirable to be able to find that ORVR systems have a specific, 

quantifiable effect on the risk of injury or fatality. Such a 

specific quantification is, however, not possible. There is no 

factual data on which to base the absolute quantification of risk 

and the estimate of casualties." This statement is a good summary 

of the report findings. The study makes no attempt to determine 

just how big the safety risk is, even in the broadest of terms. 

Neither the study's speculative arguments about complexity and 

prototype developments, nor its analytical findings, based on 

doubtful statistical methods and lab testing with little 

correlation to real world conditions, gives much basis for a 

definitive finding. NHTSA's difficulty in quantifying its 

conclusion of increased risk creates the impression that perhaps 

this increased risk, if it exists at all, is so small as to be lost 

"in the noise." 

Also quite notable is NHTSA's total lack of attention to the 

possibility of design and technology improvements in dealing with 

the potential problems they identify. Many-of these improvements 

would require no advances in technology; some are already 

contemplated by manufacturers. Finally, the report's general lack 

of objectivity, manifested in misleading and exaggerated statements 

and analysis, and a complete neglect of contrary data and opinions, 

warrants a general lack of confidence in the technical accuracy of 

NHTSA's study. This further reinforces the conclusion that the 

study is not a definitive finding on onboard system safety. 

15 
P.18 

•T,0 

Brief Summary of evap/onboard fire safety issues 7/22/91 

•Lack of statistical significance in FARS data. 

Due to the small size of the FARS database and the even smaller number of fires 

involved in fatal crashes, small variations in the number of accidents reported influence 

the fire rate. This prevents use of this data to find specific vehicle component failures as 

they relate to causing fires. Our statistical analysis shows that any changes in the years 

that evaporative controls were implemented are well within the noise of the data. NHTSA 

has gone on the record saying that FARS is too small and lacks sufficient detail to 

support such specific conclusions. Another problem with the FARS database (and most 

states) is that it did not begin until 1975. Using matched data the vehicles being studied 

are seven to thirteen years old, and much of the fleet has already been scrapped. 

•State data indicates decreasing fire rates. 

State data (Ml, MA, OH, IL, IA & more) show decreasing fire rates as evaporative 

controls were implemented. This data includes a sampling of all collisions, not just fatal 

accidents. : It doesn't look like NHTSA could use this data to prove that evaporative 

systems w^re unsafe, but they may be able to see different trends if the data was 

matched for vehicle age. 

•Cause and Effect 

As mentioned above, NHTSA does not believe that FARS can be used to pinpoint 

sources of vehicle fires. If they assert that the rise in 1970-71 was due to the introduction 

of evaporative controls, they should be able to explain the other fluctuations in the rate. 

Other things changing at the same time may have caused all or part of the change In fire 

rates. These could be things that changed in the production model-year vehicles, or 

things that caused vehicles produced at different times to see in use conditions. 

flkre S U oM» ^ CM. 

DHer Skk dak.-

•Toi l Fin,s i 
P.19 

Outline of evap/onboard fire safety issues 7/22/91 

•Lack of statistical signrflcance/noise In FARS data 

-Relative errors: 

-how have things changed over the same period? 

-Absolute errors: 

-variation in rate of 1 (1/1000) means = 20-30 fatal fires over the life of the 

fleet. (5% variation out of 2000 is 10 accidents) 

-a reporting errpr of 1 -2/yr across the entire nation would cause this amount 

of noise. 

-Statistics show that pre (68-70) and post (71 -73) evap are of the same population 

at 99.9% confidence level for both matched and unmatched data 

-If NHTSA cannot make definitive statistically significant finding for 301, how can 

they make a finding on evap fires?—see quotes to demonstrate this. 

-The data available does not extend far enough back in time to cover the early 

years of the pre-evap models. When the data is matched for vehicle age, only 

those of age 7-13 years are available and much of the fleet is off the road. 

-Talk to Terry Newell to get numbers on fleet 

-Some state data did begin earlier (SC 71 , WA 70), but there is very little available 

data. —too small of databases -includes rollovers 

-2-4 accidents =1000 accidents 

-This may be the only data available, and therefore must be used, but it is not 

robust enough to make a definitive finding on how a certain technology affectsjre 

rates. "*"" 

•State data Indicates decreasing fire rates 

-MA, Ml, OH, IL, IA data all show decreasing fire rates as evap was implemented. 

-State data includes data for all collisions, not just fatal accidents. 

-NHTSA may concentrate their efforts on state data (by matching for vehicle age 

it may show no change or increasing fire rates. 

-NHTSA may also use individual recall campaigns or other investigations rather 

than whole fleet analysis. 

-We need to take a closer look at what the state data has in it—how has it been 

manipulated? —don't have raw data M^tw^fc/iL 

-Doesn't look like NHTSA could use state data in their favor-

•Cause and Effect 

-If supposed cause/effect can be found for evap/fires in 71 , what causes produced 

the changes in 75, 77, 81, 88 etc.? 

-There are no hints of problems with evap. systems causing fires 

-safety associations 

-recalls 

-manufacturer's complaints to EPA 

-When stricter evap and exhaust emission requirements were implemented in '81, 

fire rates went down. 
P.20 

-The 1971 evap test procedure is very different than current test—used loss traps 

rather than SHED—makes extrapolation to onboard more difficult 

-Evap. was designed for 9 psi RVP fuel, but this was exceeded—may have led to 

problems. Currently RVP is set at 9 psi—will not have the same problems. 

Other things that were changing at the same time: causes of noise 

-Electrical systems-not much 

-Engine horsepower ** 1972 

-Car sizes **, but still big 

-Speed limit (55) 1974

 V 

-Fuel Volatility ** (graph) 

-Driving Patterns 

-Air Conditioning 

Graphs 

1. FARS data 1975-88 •* show variability in data 

2. FARS data 68-70 v. 71-73 (matched and unmatched) 

*• show scatter in data from year to year 

3. State data ** shows downward trend 

4. South Carolina & Washington data -^oldest data 

5. Gasoline Volatility Trends •* show increasing RVP 
P.21 

NHTSA COMMENTS ON ANALYSIS OF FIRE DATA 

Excerpts from letter to Don R. Clay, SPA, from Diane Steed, NHTSA, 

October 24,'1988. 

Page 3: "Your analysis attempts to refute comments that the 

added complexity of onboard systems could lead to an increase in 

fires by reviewing crash fire rates of current production 

evaporative control systems. You conclude that such controls "have 

had no discernible effect on vehicle fires." We disagree. The 

incidence of crash-related fires is small and national data systems 

are not designed to detect changes in the incidence of relatively 

infrequent events (i.e. crash fires). Thus we would only conclude 

that any change in the incidence of such fires, if any, is small — 

not that it is nonexistent." (bold added) 

Page 5: "We agree that it is often difficult to pinpoint the 

sources of vehicle fires involving fuel systems. As EPA has 

stated, the difficulties are due to a relatively small accident 

data base size; our FARS and NASS data files are not designed for 

identifying fuel system component failures in fires (or any other 

specific vehicle systems malfunction), etc. Therefore, it is 

difficult to prove a relationship between current evaporative vapor 

control systems and increased risks of fires in fuel systems." 

(bold added) 

Page 15: "Using FARS to conclude that evaporative controls 

had no effect on fire rates is incorrect. The FARS file^ha* 

insufficient detail to support such an implied conclusion. Any 

increase in fires due to evaporative controls would be expected to 

be small in comparison to total crash fire-related deaths and could 

easily be lost in year-to-year variation. We believe that your 

analysis shows only that fatal crash-related fires were not 

significantly increased with the introduction of evaporative 

controls. It does not and can not, using this file, address the 

prevalence of injuries or incidence of fire." (bold added) 

Based on NHTSA's past position, it does not appear likely that 

NHTSA will base any conclusions concerning the safety of onboard 

systems on an analysis of FARS data. Instead, NHTSA will probably 

make conclusions based on specific accident reports and on its past 

recall data and investigations related to evaporative controls: 

Page 5: "A NHTSA-sponsored contract, ("Study of Motor Vehicle 

Fires," JData Link, Inc., Final Report, NHTSA Docket No. 73-20-GR085, February 1988), concluded that more in-depth analysis of 

available data is needed; for example, a review of hard-copy 

accident reports to relate fuel system component failures and 

vehicle fires. The Data Link report also recommended that accident 

data of specific models should be analyzed for evaluating component 

and design attributes of the fuel systems involved in fires." 
P.22 

Fire Rates in Fatal Passenger Car Accidents 

by Vehicle Model Year (1975-88 FARS data) (NHTSA) 

25 

si 

C 

u 

T3 

' 3 20 

'J 

< 

3 

o 

| 15 

st 

U 

JJ 10 

> 

o ' ' ' ' ' ': ' ' ' i t i i i t i t t 1

 ' ' ' ' ' • • i i 

•IMI IMS INI IMT IMI l*TI \m WJ Iff) 

no \m nn nm im tm m \n* i«_ m - <*«*5S*5i?5**V ^.-;..' "^ 

Vehicle Model Year 
P.23 

Fire Rates in Fatal Passenger Car Accidents 

by Model Year (1975-86 FARS Data) (FaAA) 

1968 1969 1970 1971 

Model Year 

1972 1973 

~«_W>MSKi'-'.iSS 

197o 

I97A 

1972 

19?3 

&MTCk£D MTCH£D 

22. q- / 

24.8 

2'/.-T 

at 9 

_24,0_ 

-2^ 
P.24 

Fire Rates in Passenger Car Crashes 

by State and Vehicle Model Year (1982-87 data) (NHTSA) 

7 -

Vehicle Model Year -.t^KSJSrjt^JJ^jg^SP? 

\V 

^r 

2.1 
P.25 

Fire Rates for Car Collisions and Rollovers by Model Year 

South Carolina (1971-85), Washington (1970-85) (FaAA) 

V3 

C 

o I

 3 

"o 

U 

o 

o 

o 

^ ^ •» 

V) 

t) 

South Carolina 

Washington 

1968 1969 1970 1971 

Model Year 

1972 1973 

;-j?T»5aiC_:-

£T 
P.26 

Statistical Compairsion of Pre and Post Evap Fire Rates 

1975-86 Matched for Vehicle Age FARS Data 

10 20 30 

Fires/1000 Fatal Accidents 

-10 

« 
P.27 

0.07 

Statistical Comparision of Pre and Post Evap Fire Rates 

1975-86 Unmatched FARS Data 

10 :o 30 40 

Fires/1000 Fatal Accidents 
P.28 

Gasoline Volatility Trends 

From "Motor Gasolines. Winter 1974-75, Summer 1987" 

14 

13 

12 

_, 

> 

C_ 

10 

-•—•—•— t 

- __s * :•• ^HW^ ; 

A » • »• 

_ I I I ! I ! I I I I ! I I 

1966 1967 1968 1969 1970 1971 1972 1973 1974 1973 1976 1977 1978 1979 1980 1981 1982 1983 1984 1983 W86 1987 

Calendar Year 
Analysis of Variance (ANOVA) on FARS data obtained in the FaAA document 

HypothiwisHo: mu1=mu2: (ie the two samples are from the same population.) 

Matched Data (for vehicle age) 

Model yea 

Test Year 

1975 

1976 

1977 

1978 

1979 

1980 

1981 

1982 

1983 

1984 

1985 

19<3G 

mean 

stds 

68-70 

grandmenr 

gmnd-.lr) 

MSE 

MSTr 

140.0025 

f -, 

F.05.1.12 

F.01.1.12 

F.001,1,12 

r 1968 

21.63121 

20.81011 

16 46264 

22.24326 

25.38371 

23.1303 

24.97598 

22.09103 

2.994408 

23.70188 

5.776596 

25.52822 

5.735358 

3021438 

70.04623 

4.636615 

4 75 

9 33 

18.64 

1969 

20.90137 

17.4216 

21.33333 

22.59332 

21.66065 

37.79528 

17.89709 

22.80038 

6.891065 

1970 

18.04813 

17.7453 

25.20325 

25.6917 

30.47264 

31.43093 

34.9076 

26.21422 

6.590722 

71-73 

1971 

18 64573 

26.78571 

20.48998 

27.6907 

30.97041 

37 87268 

26.56546 

27.00295 

6.414376 

27.35457 

5.201894 

70.04623 

1972 

2347128 

25.03477 

30 41682 

35.30582 

17 12538 

32.21477 

3442029 

28.28416 

6.648237 

1973 

24.69494 

26.23907 

24.93966 

27.97877 

29 77802 

27.73925 

26.06635 

26.77658 

1.820323 

f=4.64»-F'therefore accept Ho that mul = mu2 

Unmatched Data 

Model yeaj 

Test Year 

1975 

1976 

1977 

1978 

1979 

I960 

1981 

1962 

1983 

1964 

1965 

1986 

mean 

stds 

68-70 

grand 

MSE 

MSTr 

2.287458 

f -

F.05.1.20 

F.01.1.20 

F. 001.1.20 

1968 

2163121 

20 81011 

16 46264 

2224326 

25.38371 

23.1303 

24 97598 

3£43243 

26.69039 

20.4499 

23.7467 

45.04505 

25.25014 

7.35131 

25.70937 

7.406159 

25.68761 

6.856548 

47.65117 

1.143729 

0.048004 

4.35 

8.1 

14.82 

1969 

18.63933 

20.90137 

17.4216 

21.33333 

22.59332 

21.66065 

37.79528 

17.89709 

35.62945 

21.11614 

44.11765 

31.89066 

25.91632 

8.995993 

1970 

18 01496 

24.15619 

18.04813 

17.7453 

2520325 

25.6917 

30.47264 

31.43093 

34.9076 

24.63606 

25.19685 

36 03604 

25.96164 

6.261842 

71-73 

1971 

21.78496 

21.09997 

23.70004 

18.64573 

26.78571 

20.48998 

27.6907 

30.97041 

37.87268 

26.56546 

26.28121 

43.07692 

27.08031 

7253017 

26.06585 

6.360122 

1.143729 

1972 

19.98751 

18.42644 

23.07462 

22.64365 

23.47128 

25.03477 

30.41682 

35.30582 

17.12538 

3Z21477 

34.42029 

40.56795 

26.89077 

7.493945 

1973 

20.3749 

17.67542 

18.44714 

23.00026 

23.78378 

24.69494 

26.23907 

24.93966 

27.97877 

29.77802 

27.73925 

26.06635 

24.22646 

3.792985 

f=.0480<F therefore accept Ho that mu1 = mu2 
P.30 

Brief Summary of evap/onboard fire safety issues 7/22/91 

•Lack of statistical significance in FARS data. 

iDue to the small size of the FARS database and the even smaller number of fires 

involved in fatal crashes, small variations in the number of accidents reported influence 

the fir©, rate. This prevents use of this data to find specific vehicle component failures as 

they relate to causing fires. Our statistical analysis shows that any changes in the years 

that evaporative controls were implemented are well within the noise of the data. NHTSA 

has gone on the record saying that FARS is too small and lacks sufficient detail to 

support such specific conclusions. Another problem with the FARS database (and most 

states) is that it did not begin until 1975. Using matched data the vehicles being studied 

are seven to thirteen years old, and much of the fleet has already been scrapped. 

•State data Indicates decreasing Are rates. 

State data (Ml, MA, OH, IL, IA & more) show decreasing fire rates as evaporative 

controls were implemented. This data includes a sampling of ail collisions, not just fatal 

accidents, it doesn't look like NHTSA could use this data to prove that evaporative 

systems were unsafe, but they may be able to see different trends if the data was 

matched for vehicle age. 

•Cause and Effect' 

As mentioned above, NHTSA does not believe that FARS can be used to pinpoint 

sources of vehicle fires. If they assert that the rise in 1970-71 was due to the introduction 

of evaporative controls, they should be able to explain the other fluctuations in the rate. 

Other things changing at the same time may have caused all or part of the change in fire 

rates. These could be things that changed in the production model-year vehicles, or 

things that caused vehicles produced at different times to see different 

in use conditions. 
P.31 

Outline of evap/onboard fire safety issues 7/22/91 

•Lack of statistical significance/noise in FARS data 

-Relative errors: 

-how have things changed over the same period? 

-Absolute errors: 

-variation in rate of 1 (1/1000) means * 20-30 fatal fires over the life of the 

fleet. (5% variation out of 2000 is 10 accidents) 

-a reporting error of 1 -2/yr across the entire nation would cause this amount 

of noise. 

-Statistics show that pre (68-70) and post (71 -73) evap are of the same population 

at 99.9% confidence level for both matched and unmatched data 

-If NHTSA cannot make definitive statistically significant finding for 301, how can 

they make a finding on evap fires?—see quotes to demonstrate this. 

-The data available does not extend far enough back in time to cover the early 

years of the pre-evap models. When the data is matched for vehicle age, only 

those of age 7-13 years are available and much of the fleet is off the road. 

-Talk to Terry Newell to get numbers on fleet. 

-Some state data did begin earlier (SC '71, WA 70), but there is very little available 

data, —too small of databases -includes rollovers 

-2-4 accidents =1000 accidents 

-This may be the only data available, and therefore must be used, but it is not 

robust enough to make a definitive finding on how a certain technology affects fire 

rates. 

•State data Indicates decreasing fire rates 

-MA, Ml, OH, IL, IA data ail show decreasing fire rates as evap was implemented. 

-State data includes data for aji collisions, not just fatal accidents. 

-NHTSA may concentrate their efforts on state data (by matching for vehicle age 

it may show no change or increasing fire rates. 

-NHTSA may also use individual recall campaigns or other investigations rather 

than whole fleet analysis. 

-We need to take a closer look at what the state data has in it—how has it been 

manipulated? —don't have raw data 

-Doesn't look like NHTSA could use state data in their favor—may twist data 

•Cause and Effect 

-If supposed cause/effect can be found for evap/fires in '71, what causes produced 

the changes in 75, 77, 81, 88 etc:? 

-There are no hints of problems with evap. systems causing fires 

-safety associations 

-recalls 

-manufacturer's complaints to EPA 

-insurance institute 

-When stricter evap and exhaust emission requirements were implemented in '81, 
P.32 

fire rates went down. 

-The 1971 evap test procedure is very different than current test—used loss traps 

rather than SHED—makes extrapolation to onboard more difficult 

-Evap. was designed for 9 psi RVP fuel, but this was exceeded—may have led to 

problems. Currently RVP is set at 9 psi—will not have the same problems. 

•Other things that were changing at the same time: causes of noise 

-Electrical systems-not much 

-Engine horsepower ** 1972 

-Car sizes **, but still big 

-Speed limit (55) 1974 

-Fuel Volatility * (graph) 

-Driving Patterns 

-Air Conditioning * 

•Graphs 

1. FARS data 1975-88 •» show variability in data 

2. FARS data 68-70 v. 71-73 (matched and unmatched) 

•* show scatter in data from year to year 

3. State data -* shows downward trend 

4. South Carolina & Washington data -^oldest data 

5. Gasoline Volatility Trends •* show increasing RVP 
P.33 

NHTSA COMMENTS ON ANALYSIS OF FIBS DATA 

Excerpts from letter to Don R. Clay, EPA, from Diane Steed, NHTSA, 

October 24, 1988. 

Page 3: "Your analysis attempts to refute comments that the 

added complexity of onboard systems could lead to an increase in 

fires by reviewing crash fire rates of current production 

evaporative control systems. You conclude that such controls "have 

had no discernible effect on vehicle fires." We disagree. The 

incidence of crash-related fires is small and national data systems 

are not designed to detect changes in the incidence of relatively 

infrequent events (i.e. crash fires). Thus we would only conclude 

that any change in the incidence of such fires, if any, is small — 

not that it is nonexistent." (bold added) 

Page 5: "We agree that it is often difficult to pinpoint the 

sources of vehicle fires involving fuel systems. As EPA has 

stated, the difficulties are due to a relatively small accident 

data base size; our FARS and NASS data files are not designed for 

identifying fuel system component failures in fires (or any other 

specific vehicle systems malfunction), etc. Therefore, it is 

difficult to prove a relationship between current evaporative vapor 

control systems and increased risks of fires in fuel systems." 

(bold added) 

Page 15: "Using FARS to conclude that evaporative controls 

had no effect on fire rates is incorrect. The FARS file has 

insufficient detail to support such an implied conclusion. Any 

increase in fires due to evaporative controls would be expected to 

be small in comparison to total craah fire-related deaths and could 

easily be lost in year-to-year variation. We believe that your 

analysis shows only that fatal crash-related fires were not 

significantly increased with the introduction of evaporative 

controls. It does not and can not, using this file, address the 

prevalence of injuries or incidence of fire." (bold added) 

Based on NHTSA's past position, it does not appear likely that 

NHTSA will base any conclusions concerning the safety of onboard 

systems on an analysis of FARS data. Instead, NHTSA will probably 

make conclusions based on specific accident reports and on its past 

recall data and investigations related to evaporative controls: 

Page 5: "A NHTSA-sponsored contract, ("Study of Motor Vehicle 

Fires," Data Link, Inc., Final Report, NHTSA Docket No. 73-20-GR085, February 1988), concluded that more in-depth analysis of 

available data is needed; for example, a review of hard-copy 

accident reports to relate fuel system component failures and 

vehicle fires. The Data Link report also recommended that accident 

data of specific models should be analyzed for evaluating component 

and design attributes of the fuel systems involved in fires." 
P.34 

^

uy/3 -««FARS data) (NHTSA) 

Vehicle Model Year 

J*8- * Ask m di^Uh M J «_~ it 

*•« stLirin fr ^ && 
P.35 

Fire Rates in Fatal Passenger Car Accidents 

by Model Year (1975-86 FARS Data) (FaAA) 

1968 1969 1970 1971 

Model Year 

1972 1973 

M 

49& 

i%9 

19T&-

m\ 

1972 

1973 

ftlMICITO 

2i. q- j 

2-2. T-

^i-*-. 

-24.8 

75*. O 

^3.3 

MTCHED 

21 ^ 

• ^ . 6" 

2TK* 

1e.£ 

lift 1tf£S W ((^^H^CCakleyyar), 

"lie <M> * ^*» A W« UwoleUl al 

S 3 
Fire Rates in Passenger Car Crashes 

by State and Vehicle Model Year (1982-87 data) (NHTSA) 

O ' ' ' L ' I— | I)IIIIIIIIIIII I l_ 

IW4 I W 1*» 1949 1970 1971 1971 1^73 1974 1973 197* 1977 1971 1979 19— 1911 19» I9U I9M 191] I9M 1917 

t Vehicle Model Year 

it 

1ksbU cfefe. MwctW. IH-lU k 

fe^* «-«*l dfc; 4 ewytriW c*H 

2.1 
P.37 

Fire Rates for Car Collisions and Rollovers by Model Year 

South Carolina (1971-85), Washington (1970-85) (FaAA) 

1968 1969 1970 1971 

Model Year 

1972 1973 

all We. 6sk we W . SC 4* 9 lrw*W r«Jt 

5" 
P.38 

Statistical Compairsion of Pre and Post Evap Fire Rates 

1975-86 Matched for Vehicle Age FARS Data 

0.09 

0.08 

0.07 

0.06 h 

0.05 

0.04 

0.03 

0.02 -

0.01 -

0 

0 10 20 30 

Fires/1000 Fatal Accidents 

40 50 

»'* «r_fU sWi -fU 4* nejckl m 

Siiuc Am set. 
P.39 

0.07 

Statistical Comparison of Pre and Post Evap Fire Rate 

1975-86 Unmatrh^ n A D c * V ^

 Mr e

Unmatche ^ateS d FARS Data 

Fires/1000 Fatal Accidents 

lj<> ^ 5W U ^ on^eU f?W5 
Analysis of Variance (ANOVA) on FARS data obtained in the FaAA document 

HypothesisHo: mu1=mu2: (ie the two samples are from the same population.) 

Matched Data (for vehicle age) 

Model year 1968 

Test Year 

1975 

1976 

1977 

1978 

1979 

1980 

1981 

1982 

1983 

1984 

1985 

1986 

mean 

stds 

68-70 

grandmct-un 

gnvK-std 

MSE 

MSTr 

140.0925 

f = 

F.05,1.12 

F.01.1,12 

F.001,1,12 

21.63121 

20.81011 

16.46264 

22.24326 

25.38371 

23.1303 

24.97598 

22.09103 

2.994408 

23.70188 

5.776596 

25.52822 

5.735358 

30.21438 

70.04623 

4.636615 

4.75 

9.33 

18.64 

1969 

20.90137 

17.4216 

21.33333 

22.59332 

21.66065 

37.79528 

17.89709 

22.80038 

6.891065 

1970 

18.04813 

17.7453 

25.20325 

25.6917 

30.47264 

31.43093 

34.9076 

26.21422 

6.590722 

71-73 

1971 

18.64573 

26.78571 

20.46998 

27.6907 

30.97041 

37.87268 

26.56546 

27.00295 

6.414376 

27.35457 

5.201894 

70.04623 

1972 

23.47128 

25.03477 

30.41682 

35.30582 

17.12538 

32.21477 

34.42029 

28.28416 

6.648237 

1973 

24.69494 

26.23907 

24.93966 

27.97877 

29.77802 

27.73925 

26.06635 

26.77658 

1.820323 

f_4.64<F therefore accept Ho that mu1 = mu2 

Unmatched Data 

Model year 1968 

Test Year 

1975 

1976 

1977 

1978 

1979 

1980 

1981 

1982 

1983 

1984 

1985 

1986 

mean 

stds 

68-70 

grand 

MSE 

MSTr 

2.287458 

f = 

F.05.1,20 

F.01.1,20 

F.001,1,20 

21.63121 

20.81011 

16.46264 

2Z24326 

25.38371 

23.1303 

24.97598 

32.43243 

26.69039 

20.4499 

23.7467 

45.04505 

25.25014 

7.35131 

25.70937 

7.406159 

25.88761 

6.856548 

47.65117 

1.143729 

0.048004 

4.35 

8.1 

14.82 

1989 

18.63933 

20.90137 

17.4216 

21.33333 

22.59332 

21.66065 

37.79528 

17.89709 

35.62945 

21.11614 

44.11765 

31.89066 

25.91632 

8.995993 

1970 

18.01496 

2415619 

18.04813 

17.7453 

25.20325 

25.6917 

30.47264 

3143093 

34.9076 

24.63606 

25.19685 

36.03604 

25.96164 

6.261842 

71-73 

1971 

21.78498 

21.09997 

23.70004 

18.64573 

26.78571 

20.48998 

27.6907 

30.97041 

37.87268 

26.56646 

26.28121 

43.07692 

27.08031 

7.253017 

26.06585 

6.360122 

1.143729 

1972 

19.98751 

18.42644 

23.07462 

22.64365 

23.47128 

25.03477 

30.41682 

35.30582 

17.12538 

32.21477 

34.42029 

40.56795 

26.89077 

7.493945 

1973 

20.3749 

17.67542 

18.44714 

23.00026 

23.78378 

24.69494 

26-9907 

24.93966 

27.97877 

29.77802 

27.73925 

26.06635 

24.22646 

3.792985 

f=».0480<F therefore accept Ho that mu1 a mu2 

H»5 b\V JUSU GOM* 

o 
P.41 

Gasoline Volatility Trends 

_* 

From NIPER's "Motor Gasolines" 

15 

14 

13 

"3 12 winter. 

II 

10 

' ' • I I I—I I I I 1—J I 1 1 L_ 

i9« IMT IMI iwt m ICTI an im irw im m* \m wn \<m am mi m m> IM IMJ KM IMT 19— am iwo 

Calendar Year 

i l « ffofl sk^i <}L iWOfo |wl VkUil.*^ 

U& W i^fe U^U fefc t* t ^ fc* lb \ 

Life W* (At. t