UL-FPRF Smoke Characterization Project
In 2006 in conjunction with the Fire Protection Research Foundation (FPRF) of the NFPA, and as a follow up to a 2004 NIST study (Bukowski, R.W. et al., "Performance of Home Smoke Alarms-Analysis of the response of several available technologies in residential fire settings," NIST Technical Note 1455, National Institute of Standards and Technology, Gaithersburg, Md., July 2004, Reissued 2008.), UL initiated a Smoke Characterization Project. In the earlier NIST study, researchers observed a reduction in available safe egress times, attributed to significantly faster fire growth caused by the types of materials used in modern furnishings.
The purpose of the UL-FPRF Smoke Characterization Project was to more fully characterize the products of both flaming and non-flaming combustion on a variety of products and materials typically found in residential settings. This study used smoke particle and gas effluent characterization technology that had not been previously available for commercial testing purposes.
Testing scenarios included the standard UL 217 smoke alarm fire test protocols and products commonly found in residential occupancies such as coffee makers, toasters, carpeting, and bedding and upholstered furniture components.
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Smoke from (left) flaming fires and (right) smoldering fires. |
The Smoke Characterization Project study produced the following key findings:
- Synthetic materials ignite faster than natural materials, burn more intensely and create greater amounts of smoke and other types of gases.
- The response time of photoelectric and ionization smoke alarms was influenced by different smoke particle sizes and counts due to changes in the combustion mode (flaming versus non-flaming).
- Commercially available ionization smoke alarms triggered earlier than commercially available photoelectric smoke alarms for flaming and high energy non-flaming (toaster) fires.
- Photoelectric alarms triggered earlier for lower energy non-flaming fires.
- Smoke from low energy non-flaming fires was found to stratify with time.
Based upon the results of this Smoke Characterization Project, the following items were identified for further consideration:
- The addition of other test materials such as polyurethane foam in the flaming and non-flaming combustion modes in UL 217.
- Whether a smoke alarm, once triggered, should remain activated unless deactivated manually.
- Requiring the use of combination ionization and photoelectric alarms for residential use in order to maximize responsiveness to a broad range of fires.
- Characterize materials described in UL 217 using a cone calorimeter, smoke particle spectrometer, and analytical testing.
The full report of the Smoke Characterization Project is publicly available at http://www.nfpa.org/assets/files/PDF/Research/SmokeCharacterization.pdf.
Data generated during the course of the project can be downloaded via the following link:
UL-FPRF Smoke Characterization Project - data files (*.xls 72 MB)
Publications
Fabian TZ, Gandhi PD, Patty PE, Chapin JT (2009) Characterization of combustion products under flaming and non-flaming conditions. In: Proceedings of Fire & Materials 2009 11th international conference
