Group Research & Development Centre,
British-American Tobacco Co. Ltd.,
SOUTHAMPTON.
FJD/RA/46C-1 3rd December, 1980
SIMULTANEOUS PUFF BY PUFF FILTER AND
TOBACCO ROD VENTILATION MEASUREMENTS
(Report No. RD.1768 Restricted)
SUMMARY
Puff by puff ventilation profiles through the
tobacco section and
the filter have been measured simultaneously for
cigarettes with naturally
porous and electrostatically perforated cigarette
papers having
permeabilities up to 340 CORESTA units and for
filters with up to 80Z
unlit ventilation both separately and in various
combinations.
There is usually an increase in ventilation on the
Ist and 2nd puff
followed by a decrease in the later puffs. For
cigarettes having
conventional cellulose acetate filter, profile
shape is not affected
by the hole size and pattern or the position of
the holes in the filter.
However the total ventilation profile is changed
considerably depending
on the contribution to the ventilation level by
the cigarette paper and
tipping. If most of the ventilation is through the
paper then the overall
profile shape follows that of the paper.
Conversely if most of the
ventilation is through the tipping and that
through the paper is low then
a fairly even profile is obtained. This is
important in cigarette design.
By minimising the reduction in ventilation during
the later puffs, the
puff by puff deliveries will be moved in the
direction of a more even
profile.
BATCO document for Province of BritiSh Columbia 3
November 1999


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The next stage of this study is to measure the
puff by puff smoke
deliveries of some of the above cigarettes and to
investigate how the
profile shape can be modified to improve the smoke
characteristics of low
delivery cigarettes in the early puffs.
Uli
BATCo document for Province of BritiSh Columbia 3
November 1999