Introduction
On November 22, 2012, “a fire in a two and one-half story residential structure” that was attended by a Chicago Fire Department crew resulted in the death of a Captain (National Institute of Standards and Technology [NIST], 2014a). The main reason for this outcome consisted in the “thermal degradation and failure of the rear porch door,” which led to a fire path change and the subsequent increase in temperature and gasses that altered the conditions from tenable to untenable very rapidly (National Institute of Standards and Technology [NIST], 2014b). In this paper, the case study is considered from the point of view of the applicable building codes, materials used, and the lessons learned.
Building Codes
The International Association of Fire Chiefs [IAFC], National Fire Protection Association, and Jenaway (2012) require analyzing a building with the help of the specific jurisdiction code with occasional referral to the NFPA 101, Life Safety Code and, optionally, NFPA 220, Standard on Types of Building Constructions (pp. 104-105). Given the fact that the building was located in Chicago, the Chicago Municipal Code would be the applicable document in this situation.
The Chicago Code is a local set of requirements that had been changed and updated repeatedly. The idea of regulating buildings to maintain a healthy environment had been approached in 1827 by the Chicago’s Health Department, but a code of the relevant regulations was created only in 1875 (Bigott, 2005, para. 1). Since then, its amendments and reforms reflected the struggles between the Department of Buildings that sought minimal requirements and reformists who attempted to improve the environment. Besides, as the building industry developed, updates needed to be made. The current Municipal Code of Chicago (2016) was first published in 1990, and it is a modern and comprehensive document that is aimed at improving the protection and safety of the Chicago population.
NFPA 220 was developed by the National Fire Protection Association (2015b), and it provides the definitions of the “types of building construction based on the combustibility and the fire-resistance rating of their structural elements” (para. 1). It takes into account the key elements of the structure and names five types of construction. The current, eleventh edition was developed in 2015; the first one was created in 1974. NFPA 101 or the Life Safety Code® was also developed by the National Fire Protection Association [NFPA] (2015a) to become the most popular and widely used code that provides guidelines on safety and protection.
It includes provisions for “all types of occupancies, with requirements for egress, features of fire protection, sprinkler systems, alarms, emergency lighting, smoke barriers, and special hazard protection” (NFPA, 2015a, para. 2). The current edition is dated 2015; there were 16 more editions, and the first one had been developed in 1966. Each revision of NFPA codes involves multiple reviews of drafts that are open to public comments at the NFPA website for NFPA members and National Fire Codes Subscription Service subscribers. The three codes can be used to assess the safety of the case study building.
Materials, Their Properties, and Tests
Since the failure of the door caused the case study’s tragic outcomes, its materials are of special interest. The door was steel-faced and wood-framed; the rest of the house was made of gypsum board and wood, which made it a wood-frame, type V construction as classified in the NFPA 220 (IAFC et al., 2012, p. 21). All the mentioned materials are often used in building, which is why all their properties have been studied and tested for various purposes (IAFC et al., 2012; Olomo, Aderinlewo, Tanimola, & Croope, 2012).
There are varieties of steel and wood; steel can be modified to serve particular purposes, and wood can possess various specifics that affect its behavior when exposed to fire. However, the NIST (2014a) note does not comment on the specific type of material. It does point out, though, that the door deformed just above the knob (p. 34). NIST (2014a) also carried out experiments with similar doors, during which such degradation (with the doorknob serving “as a pivot point for the upper portion of the door to collapse around”) happened again (p. 24).
According to IAFC et al. (2012), steel is the strongest building material, but it is not fire-resistive. It requires protection from heat to avoid its expansion and deterioration. In the case, the door was steel-faced, which is why it can be considered unprotected. Gypsum boards are panels “consisting of a layer of compacted gypsum sandwiched between two layers of specially produced paper” (IAFC et al., 2012, p. 16). This material can be used to protect a structure since the paper burns very slowly and does not produce enough heat to contribute to the fire spread. However, it does deteriorate when subjected to heat and will fail under prolonged exposure.
In the case structure, the gypsum board protected the wood that was used for its construction. IAFC et al. (2012) state that wood is most commonly used for building due to its accessibility and usability; however, it is very combustible and produces large quantities of heat and gasses when on fire. Also, it is easily consumed by the fire, thus opening new paths and weakening the structure. NIST (2014a) carried out an experiment to define the “heat release rate per unit area” for different types of wood, and the results indicated approximately 50 kW/m2, which allowed NIST (2014a) to make the calculations for the simulation of the fire in the case study.
Lessons Learned
This case demonstrates the danger of rapidly changing fire flow paths, which may result in suddenly untenable conditions. It shows that a structural component that fails can produce rapid change and cause-related negative consequences. This is not the only possible reason; for example, environmental conditions are also capable of leading to such consequences, but in this case, the death of the Captain of Chicago Fire Department was the result of door material thermal degradation and the subsequent “rapid increase in temperature and fire gases” (NIST, 2014b).
For builders and building code developers, the present case and its study demonstrate the consequences elements and material failure. Studying the properties of materials, defining standards for them, and ensuring their enforcement, are the means of improving fire protection and people’s safety (Olomo et al., 2012). However, NIST (2014b) explains that for firefighters, the prediction of structure components failure time or mode is not a realistic option since they typically lack information and have to deal with uncertainties.
As a result, for firefighters, the case study demonstrates the importance of taking into consideration the problem of path changes. NIST (2014b) conducted a study that demonstrated the effectiveness of exterior attacks with a straight or solid stream of water in improving the safety of firefighters. Apart from that, NIST (2014b) instructs to develop and coordinate ventilation and suppression tactics while keeping in mind potential flow paths. The problem that is demonstrated by this case study can be taken into account and controlled both by building code developers and firefighters.
References
Bigott, J. (2005). Building Codes and Standards.
International Association of Fire Chiefs, National Fire Protection Association, & Janeway, W. (2012). Fire Inspector: Principles and practice. Burlington, MA: Jones & Bartlett Learning.
Municipal Code of Chicago. (2016).
National Fire Protection Association. (2015a). NFPA 101: Life Safety Code®.
National Fire Protection Association. (2015b). NFPA 220: Standard on Types of Building Construction.
National Institute of Standards and Technology. (2014a). Simulation of an attic fire in a wood frame residential structure – Chicago, IL (NIST Technical Note 1838).
National Institute of Standards and Technology. (2014b). Simulation of an attic fire in a wood frame residential structure—Chicago.
Olomo, O., Aderinlewo, O., Tanimola, M., & Croope, S. (2012). Assessment of the material properties of a fire-damaged building. Construction, 13(2), 16-23. Web.