Document 4vnyNg90nagDj0DG40b50e4ER
FILE NAME: Asbestos in Hair Dryers (HD) DATE: DOC#: HD0 OCUMENT DESCRIPTION: 'DZZZZZZ&Z
TI1(' Gill. C ,An Ofllf )( IflY
...., P.,.,l 'A., ....'fu. r : ( ,... f (
Infer-orfc; ~
u",. August' 28, 1975
~... to. F.
Comparf~on of Coil Failure Rates
,
I. w. J. C. Johnson
.."1'-'
, , :'It '" R. Flynn
...
._~.,
To
tl;~
best
of
my
knowledge, no failures
one has answered the quest'i;;-ri compares with failure rates ',..
0 tow tr. ted
bothyfeothrtaehteeorthoGefirlHldeOrt-t1ye2erchso,aiilrItdcroyuelrds. altIef rththeerap~terspoef~tf1avileurcef ithsesfp.ril~~~~.to tha
Comp.!rat1ve coil
failure
rates
for
tiD-12 and
two
other dryers ~re: as
"~
follows:
,~
%of Field Qty. ,;~,
HD-12
IJ.04
",:, ,~~
HO-7
0.14
HO-5
~.02
These
figures
renpthres seonft raeturarntisooovfer ththeecucomrurelasptiovnedinru.gmb~frielodf
coil fal ure quantity.
after eleven mo 8ec~use of the form
o
f
the
~open
hi c
storic 0115,"
a
l "
s
inform horted
ation cof1
a s.
v "
aila and
b
le, "ha
i ir
t
was
entan~le
necessary ment wHh
tormcocnosiidlse"r together
op
ation was
alsimointeedtytope thoefs'feaitlhureree. moIdneltsh.e
fnterEit '
of time. the investig
M3thcmatical
analysis to pl'oxima"ion
estimate the probability of of the warranty period used
fa1lure after 15 in ~revious anal:'se
months (an ap resul ted ill the
fol lowing:
REeEJ
Model
p [failure]
HO-12
0.251
SEP 3
HHOO--SJ 00..7146 GPwE
The
1"(~1'ltion5hip cl1r.OnlJ the
initial compclrison,
t
hree models II.Jwever. th
e
i
s roughly .)CClJrilcy
o
th f
e sante
th~se
as ;ndicat,~d probabi 1 i ly
hy the
ited Ily the (det trlat coil failure frCljuenc;cs could n. t
c<,tllll,ltc5 is lIm be illcnlif';".j ,...,th
~'I'('ci(ic
Jot nuObl!r'l,
CONFIDENTIAL
.....
G 00495
. ':," .,.. . . .
August 28. Comparison
1o9f75Con
Failure
Rates
Page 2
This
analys~s
doHesowsheovwer, thHaOt-1H2 0c-1o2ilcofaililufraeilsuraerse
are not occurring at an probably more spectacular
abnormal rate. since once the
~pen occurs. and short to
othteh elroocsoei l sen. -ds: r haer eofnrleye"obtoviomuosve dainf fyewrheenrec e in
btheetwheeenatHceorOr-bd1o2sx. andThainsycoouthlderbGe itlhleetcterfhtaici~(~. rdyieffreriesncthee. absence"of heater -
support
J~ ~ ~~Li;7e'~. JCJ/sdc
.
1/
:I. r' o
l.~f,'
f"
G 00496