# OAR Box 1818

Prepped by Ollie Stewart



### Document

Number: 

# 9 ) ll-C- 6 Docket Number: 

# A-87-1 1

Printed 11/6/2008 3:12:41 PM Sheet 9 of 79 p. 1P. 2

av^ ° Sr < V 

# IS K /)-<??-/ / I^C'lX,

UNITE D STATE S ENVIRONMENTA L PROTECTIO N AGENC Y >« . —^c fWASHINGTON

. D.C

. 2046 0 " V PBOl* - FE B I 2 iS3 7 TH E ADMINISTRATO R Mr . Thoma s H . Hann a Presiden t Moto r Vehicl e Manufacturer s Associatio n 30 0 Ne wCente r Bldg . Detroit , M I 4820 2 Dea r Mr..Hanna : Than k yo u for your lette r o f Decembe r 2 2 outlining for m e •cn e ke ysafet yissue s whic h yo u fee l mus t be addresse d a s par t o f th e refueling contro l decisio n making process . I appreciat e you r concer n tha t thes e area s receiv e prope r attention , relating a s theyd o t o issue s o f vehicl e safet yan d cost . I n you r lette r yo u identifie d thre e mai n safet yconcerns : fue l system

integrity , fue l spitbac k an d fue l dispensin g nozzl e failure . I n the firs t are a yo u describe d concern s wit h th e effec t o f onboar d refueling hardwar e o n th e fue l containmen t requirement s o f Federa l Moto r Vehicl e Safet yStandar d (FMVSS ) No . 301 . Fue l spitbac k yo u describ e a s a concer n abou t th e spillag e o f fue l backe d u p i n the fille r nec k a t th e en d o f a refueling operation . A s fo r nozzl e failure , thi s concer n relate d t o malfunction s o f the automati c shutof f mechanis mo n the fue l fille r nozzle . I agre e tha t eac h o f thes e area s i s deservin g o f carefu l attentio n an

d thorough study . A s yo u know , w e hav e alread y devote d attentio n t o thes e area s in respons e t o simila r question s raise d i n the past . Additionally , a s par t o f ou r coordinatio n proces s wit h Nationa l HighwayTraffi c Safet y Administratio n (NHTSA ) o n th e safet yimpact s o f onboar d controls , w e ar e currentl yinvolve d in supplementa l analyse s addressing severa l safet ymatters . Thes e analyse s includ e looking a t issiues such a s thos e whic h yo u raise . i• , Th e over-al l philosoph ywhic h we appl yt o thi s are a i s tha t no increas e i n overal l ris k shoul d b e accepte d becaus e o f the presenc e o f onboar d contro l systems . No r doe s thi s concer n stop a t th e demonstratio n o f complianc e wit h FMVS S 301 . I t appear s t o u s tha t the overal l safet yimpact s for in-us e vehicle s mus t b e evaluate d fro mthe broade r system s approach , recognizing th e fac t tha t in-us e liabilit yca n exis t fo r condition s no t covere d b ythe Federa l standards .P. 3

-2

- O f course , the fina l choice s abou t exac t system design s wil l be wit h the manufacturers , bu t we woul d no t adop t a progra munles s i t wer e clea r tha t saf e fue l systemdesign s wer e available . A t thi s tim e we ar e convince d tha t thi s i s the case . I n fact , our analyse s indicat e tha t i t woul d be quit e possibl e fo r fue l systemsafet yt o improv e along wit h th e adoptio n O f onboard controls . On e exampl e o f ho wthi s migh t occur woul d be through the us e o f flexibl e bladder s insid e th e fue l tan

k t o contai n the liqui d fue l an d eliminat e th

e presenc e o f an yfue l vapors . Suc h containmen t woul d improv e fue l system safet yan

d als o eliminat e the nee d for muc h o f the evaporativ e contro l hardwar e alread yo n curren t vehicles . Ther e ar e othe r aspect s o f overal l fue l systemdesign whic h migh t be modifie d a t the tim e o f introducing onboar d controls . Suc h thing s a s the placemen t an d configuratio n o f th e fue l tank , the us e o f sid e fil l versu s rea r fil l fueling designs , externa l versu s interna l fueling vapo r ven t lines , etc . ar e al l area s o f design determine d a s a result , o f tradeoff s betwee n competing design goals . W e believ e tha t curren t fue l systemdesign s can b e improve d i n such area s a s thes e an

d tha t the safet yo f onboar d equippe d vehicle s nee d no t b e compromised . Le t me briefl yrespon d t o the specifi c concern s raise d i n you r letter . You r firs t ite mconcerne d complianc e wit h FMVS S 301 . Bot h fro

m our ow

n analysi s an

d fro mour contact s wit h NHTSA , we believ e tha t complianc e wit h thi s requiremen t wil l be relativel ystraightforwar d give n sufficien t leadtime t o complet e th e require d test s an d evaluations . W e agre e tha t cras h relate d issue s mus t b e factore d int o onboar d system designs , bu t we d o no t fin d onboar d technolog yt o b e substantiall ydifferen t fro mcurren t evaporativ e controls . Fo r example , the concer n ha s bee n raise d tha t the large r onboar d caniste r mean s tha t a substantiall ylarge r amoun t o f fue l vapor s wil l hav e t o be carrie d aroun d o n the vehicle . However , thi s wil l no t generall y. be th e case , sinc e fo r the grea t majorit yo f th e tim e the onboar d caniste r wil l no t contai n an y mor e vapor s than the curren t evaporativ e contro l canister . Refueling vapor s wil l b e purge d t o th e engin e an d burne d a s fue l withi n a relativel yfe wdriving mile s following a refueling . Similarly , a s yo u indicat e i n you r letter , large r vapo r line s will , have t o be deal t wit h i n some onboard designs , bu t thi s does ; not appea r t o b e an overwhelmin g engineerin g problem . Over&ll , a s describe d above , w e believ e tha t issue s o f tota l vehicl e safet yan d in-us e liabilit ywil l resul t i n n o increas e i n vehicl e safet yrisks , an d ma yeve n lea

d t o safet y improvement s i f safet yconcern s s o dictate . You r secon

d concer n involve d fue l spitbac k a t the en d o f th e refueling operation . Becaus e o f th e requirement s o f ou r testing procedure s fo r onboar d controls , onl ysystem s capabl e

# T P. 4

-3

- o f eliminating spitbac k (which , a s yo u know , occur s o n curren t vehicles ) wil l be abl e t o mee t an yrefueling contro l standard . W e have ha

d discussion s wit h vehicl e manufacturer s concernin g th e cause s o f spitback , an d hav e eve n bee n considering th e possibl e nee d for design requirement s fo r dispensin g nozzles . I f onboar d requirement s wer e adopted , we woul d als o pla n t o contro l th

e dispensing rate s for in-us e nozzle s in orde r t o assur e the contro l o f spitback . Overall , we woul d expec t the incidenc e o f spitbac k t o b e les s wit h onboar d control s than i s currentl ythe case , resulting in a n improvemen t i n th e safet y issue s relativ e t o fue l spitback . Finally , yo u rais e th e questio n o f the possibl e failur e o f the automati c shutof f featur e o n th e fue l dispensin g nozzle . W e agre e tha t ther e mus t b e a mechanis mwhic h wil l aler t th e operato r in the even t o f such a failur e withou t causing a dangerou s conditio n t o exist . Simpl e pressur e relie f design s have alread

ybee n develope d whic h woul d direc t backe d u p fue l ou t nea r the fille r nec k muc h a s happen s wit h curren t vehicles . Yo u sugges t tha t i t migh t be mor e appropriat e t o implemen t change s in the fue l nozzl e itself . W e woul d b e ope n t o considering the nee d fo r suc h change s an d woul d welcom e mor e informatio n fro

m yo u abou t the specifi c change s involved , an d thei r cos t in relatio n t o the onboar d hardwar e feature s o.therwis e required . I n closing , I wan t t o than k yo u for taking the tim e t o conve yyou r concern s t o EPA . Le t me assur e yo u tha t I a m committe d t o the ful l resolutio n o f al l safet yissue s surrounding th e us e o f onboar d controls . You r inpu t ca n b e a valuabl e hel p a s we continu e wit h thi s task . Sincerely , / * / Le e M . Thoma s