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Engineering Laboratory / Fire Research Division

National Fire Research Laboratory

CB-42-DA-4MW

Table 1. Test Information
Name
CB-42-DA-4MW
Date
Description

Loaded 42 ft composite beam floor test with 3 natural gas burners ramp to 4 MW over 10 min. 3 x 4000 lbs point load. Double angle steel connection to column.
Specimen
Three box burners
Ignition
pilot flame
Project ID (s)
Steel-Concrete Composite Floor Systems Subject to Fire, Phase 1
Test Director
Choe

Timelapse Video with Heat Release Rate Plot

Table 2. Summary of Test Results
Measurement Value Uc Unit
Peak Heat Release Rate, PHRR
4,182
216
kW
Time to Peak Heat Release Rate
14.77
0.17
min
Total Heat Released, THR
10,980
576
MJ
Natural Gas Burner Total Heat Released, NGTHR
10,772
154
MJ
Heat Release Quality Confirmation, HRQC
 Not measured -
MJ/MJ
Net Specimen Mass (gravimetric), NM = Mi-Mf
 Not measured -
kg
Total Fuel Mass Burned, TFM = THR / HOCf
220
13
kg
Net Effective Heat of Combustion = THR / NM
 Not measured -
MJ/kg
O2 Yield = O2 Consumed / TFM
3.64
0.25
kg/kg
CO2 Yield = CO2 Generated / TFM
2.92
0.21
kg/kg
CO Yield = CO Generated / TFM
0.01199
0.00084
kg/kg
Soot Yield = Soot Generated / TFM
 Not measured -
kg/kg
Baseline Hood Exhaust Flow
80.8
2.4
kg/s
Test Duration = Time(Fire Out) - Time(Ignition)
67.92
0.03
min

Uc = Combined Expanded Uncertainty with 95% confidence level

Table 3. Summary of Test Input Parameters
Parameter Value Uc Unit
Fuel Type
Natural Gas
 - -
Hood Size
15
 -
m
Effective Duct Diameter
2.424
0.009
m
Exhaust Flow Correction Factor
1.042
0.032
 -
Net Heat of Combustion (per unit mass O2), Ef
12.54
0.50
MJ/kg
Net Heat of Combustion(per unit mass fuel), HOCf
50.00
1.50
MJ/kg
Initial Specimen Mass, Mi (gravimetric)
 Not measured -
kg
Final Specimen Mass, Mf (gravimetric)
 Not measured -
kg
Plot of Fire Heat Release Rate with event markers. Uncertainty bar shown at peak value.
Figure 1. Plot of Heat Release Rate data with event markers and error bars shown at peak.
Table 4. Summary of Observed Test Events
Event Time (min) Description Video Snapshot Image
1
-87.45
data sync marc
data sync marc
2
-84.20
start loading floor beam ramp ofr 15 m and hold for 15 m at 12 kips over 3 points
start loading floor beam ramp ofr 15 m and hold for 15 m at 12 kips over 3 points
3
-25.12
hold loading at 24 kips- spread over 6 points
hold loading at 24 kips- spread over 6 points
4
0.00
Ignition
Ignition
peak
14.77
Peak HRR
Peak HRR
5
30.62
load decreased
load decreased
6
35.40
starting cooling phase - ramp burner off over 30 min
starting cooling phase - ramp burner off over 30 min
7
67.92
Fire Out
Fire Out

Table 5. Supplemental Data Plots

Plot of Oxygen Dry Volume Fraction in hood exhaust stream.
Plot of Oxygen Dry Volume Fraction in hood exhaust stream.
Plot of Carbon Dioxide Dry Volume Fraction in hood exhaust stream.
Plot of Carbon Dioxide Dry Volume Fraction in hood exhaust stream.
Plot of Carbon Monoxide Dry Volume Fraction in hood exhaust stream.
Plot of Carbon Monoxide Dry Volume Fraction in hood exhaust stream.
Plot of Radiant Heat Flux data with event markers. r= radial distance from center of hood, h=height above floor.
Plot of Radiant Heat Flux data with event markers. r= radial distance from center of hood, h=height above floor.
Plot of Smoke Laser Extinction Coefficient in hood exhaust stream.
Plot of Smoke Laser Extinction Coefficient in hood exhaust stream.
Plot of Exhaust Duct Mass Flow Rate.
Plot of Exhaust Duct Mass Flow Rate.

Bryant, R. and Bundy, M. The NIST 20 MW Calorimetry Measurement System for Large-Fire Research, Technical Note (NIST TN) 2077, 2019
https://doi.org/10.6028/NIST.TN.2077

NIST Fire Calorimetry Database (FCD)
https://doi.org/10.18434/mds2-2314

Report Process Script Version
NFRL_Report_8.3.4
Last Updated June 8, 2021