Section IV 
Figure 5 
Mean total puffs per session (N = 4) and standard error values for each subject as 
a function of cigarette holder number 
I Ventilated Holder 
Note: The approximate concentrations of delivered tobacco product are indicated by the holder 
number in which 0= 100 percent, 1 = 75 percent, 2 = 50 percent, and 4 = 10 percent. The 
’ abbreviations ST, ED, and GR represent three paid female volunteers who participated in the 
1 study. 
Source: Henningfield and Griffiths, 1980. 
i machines. Ventilation holes were blocked with tape. The researchers 
! compared standard yields of cigarettes to yields resulting from the study- 
determined parameters and blocked ventilation holes; they observed that 
"tar increases from 15- to 39-fold, nicotine from 8- to 19-fold and CO from 
10- to 43-fold" (Kozlowski et al., 1982a, p. 159). Five cigarette brands similar 
I in tar yield were found to differ substantially when parameters were changed 
' and holes blocked. 
I In a later study of 14 subjects, Kozlowski (1989) detected hole blocking 
' by half the sample. Subjects blocking the ventilation holes of ultralow-yield 
i 
263 
