5
.1 97 10 m VACO
2 CO
2
#=-3 o
.1 25 10 m VACO
CO
#=-3 o
RESULTS AND DISCUSSION
Figure 4 depicts the estimated HRR of a typical positive
suppression test. The onset of the spray fire is marked with
a small red circle. A few seconds after that, the HRR starts
growing which is based on the result of CO and CO2 gas
concentrations measured at the gas analyzer. The delay is
the result of the travel time of the CO and CO2 gasses.
It takes approximately 60 seconds for the fire to stabilize
which can be seen from the HRR curve leveling off. At
this time, the fire suppression system is engaged and sup-
pression is initiated which is indicated by a rapid drop of
the fire HRR as the result of diminishing the fire output,
CO, and CO2 gasses. This is the result of a positive fire
suppression test. In addition to interpreting the collected
data and calculating the HRR, the fire suppression test is
visually verified on the recorded video.
Figure 5 shows the evolution of the fire HRR for a
typical negative suppression test. After the suppression
system initiated, a temporary drop in the HRR curve can
be seen which can be attributed to a partial suppression of
fire. However, since the fire is not fully extinguished after
the suppressant is depleted, the fire starts growing as indi-
cated by the increase in the HRR around 120 seconds into
the test.
Typical gas temperature patterns during positive and
negative suppression tests are shown in Figures 6 and 7,
respectively. The gas temperature at the installed tempera-
ture points are also identified in the figure corresponding to
their distance from the floor in inches and the correspond-
ing airflow rate in Feet Per Minute (FMP). Similar to the
evolution of the fire HRR, in a typical positive suppression
test the gas temperature increases until the fire suppression
is initiated. Once the suppression is initiated, the gas tem-
perature drops to the pre-fire condition. A typical negative
suppression test shows an increase in the gas temperature.
Once the suppression is initiated, the gas temperature
decreases temporarily until the suppressant is depleted.
Figure 4. Fire size, HRR, evolution during a typical positive suppression test
.1 97 10 m VACO
2 CO
2
#=-3 o
.1 25 10 m VACO
CO
#=-3 o
RESULTS AND DISCUSSION
Figure 4 depicts the estimated HRR of a typical positive
suppression test. The onset of the spray fire is marked with
a small red circle. A few seconds after that, the HRR starts
growing which is based on the result of CO and CO2 gas
concentrations measured at the gas analyzer. The delay is
the result of the travel time of the CO and CO2 gasses.
It takes approximately 60 seconds for the fire to stabilize
which can be seen from the HRR curve leveling off. At
this time, the fire suppression system is engaged and sup-
pression is initiated which is indicated by a rapid drop of
the fire HRR as the result of diminishing the fire output,
CO, and CO2 gasses. This is the result of a positive fire
suppression test. In addition to interpreting the collected
data and calculating the HRR, the fire suppression test is
visually verified on the recorded video.
Figure 5 shows the evolution of the fire HRR for a
typical negative suppression test. After the suppression
system initiated, a temporary drop in the HRR curve can
be seen which can be attributed to a partial suppression of
fire. However, since the fire is not fully extinguished after
the suppressant is depleted, the fire starts growing as indi-
cated by the increase in the HRR around 120 seconds into
the test.
Typical gas temperature patterns during positive and
negative suppression tests are shown in Figures 6 and 7,
respectively. The gas temperature at the installed tempera-
ture points are also identified in the figure corresponding to
their distance from the floor in inches and the correspond-
ing airflow rate in Feet Per Minute (FMP). Similar to the
evolution of the fire HRR, in a typical positive suppression
test the gas temperature increases until the fire suppression
is initiated. Once the suppression is initiated, the gas tem-
perature drops to the pre-fire condition. A typical negative
suppression test shows an increase in the gas temperature.
Once the suppression is initiated, the gas temperature
decreases temporarily until the suppressant is depleted.
Figure 4. Fire size, HRR, evolution during a typical positive suppression test