III. RESULTS AND DISCUSSION
A.
Aerosol Monitor Calibration
Calibration data for the Delta 3000 were collected previously by ENVIRON (2002). To
develop a calibration curve for each glycol fluid, the average aerosol monitor readings for each
air sample were calculated and plotted against the total glycol concentration data. The
calibration curves for the glycol fluids tested are shown in Figures 3 to 6. First order regression
curves are also shown on these figures. The calibration factors for the glycol fluids, calculated
from the slopes of these regressions, are summarized in Table 1.
TABLE 1
Summary of Calibration Factors
Rosco Delta 3000 Fog Machine
Machine Fluid
Calibration Factor,
(ug/L)/(mg/m
3
)
Rosco Clear Fog Fluid
1.43
Rosco Fog Fluid
1.00
Rosco Light Fog Fluid
1.35
Rosco Delta 3000
Rosco Stage & Studio Fluid
1.97
Reference: ENVIRON (2002)
B.
Peak Exposure Characterization
For 100% and 50% settings, monitoring data collected using aerosol monitors placed at
distances of 5, 10, 15, 20, 25, and 30 feet from the Delta 3000 machine were combined with the
calibration factors to determine the levels of smoke at different distances from the release point
and times following the release. For the 10% setting, the monitors were placed at distances of 3,
6, 9, 12, 15, and 18 feet. The real-time aerosol monitor readings were converted to glycol
concentrations using the appropriate calibration factor for the fluid, as follows:
PDR
C
CONC
×
=
where:
CONC
= air concentration of total glycols,
µ
g/L
C
= aerosol monitor calibration factor (from Table 1), (
µ
g/L)/(mg/m
3
)
PDR
= aerosol monitor reading, mg/m
3
ROSCO DELTA 3000
-6-
E N V I R O N
