AUTHOR: Sreenivasan Ranganathan

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Just Weeks After Fatal Baltimore Explosion, Fire Protection Research Foundation Releases New Research on Combustible Gas Dispersion and Detector Location Analysis

According to research from NFPA, an estimated 4,200 home structure fires and an average of 40 deaths result annually when natural gas is ignited. The devastating outcome of a combustible gas leak within a residence was on full display recently when three rowhouses in Baltimore exploded, killing two and injuring seven. While gas detector placement information is available within manufacturer recommendations, NFPA does not currently have a standard containing more specific prescriptive-based detector placement requirements supported by technical review. NFPA 715, Standard for the Installation of Fuel Gases Detection and Warning Equipment, however, is currently in the early developmental stages prior to beginning full public review. NFPA 715 will help to minimize tragic incidents like we saw in Baltimore on August 10th and in the Merrimack Valley region of Massachusetts last year when a series of more than 80 explosions and fires occurred in approximately 40 homes, killing one and forcing 30,000 to evacuate their residences. NFPA 715 will cover the selection, design, application, installation, location, performance, inspection, testing, and maintenance of fuel gas detection and warning equipment in buildings and structures. The Fire Protection Research Foundation, the research affiliate of NFPA, recently completed a report studying combustible gas leaks and dispersion in residential buildings, as well as an analysis of combustible gas detector placement to provide the necessary technical basis to justify the requirements in NFPA 715. Computer modeling was used to quantitatively evaluate the impact that placement has on gas detector performance in residential occupancies. Natural gas and liquefied petroleum gas releases were simulated in different residential structures, and gas concentrations were tracked at numerous potential detector locations within these buildings to determine which locations are most effective for reliable and early detection. Overall, more than 250 simulations were performed with a wide range of plausible leak types and environments to produce the most robust technical basis upon which gas detector location recommendations can be made. A hazard-based approach was also applied to understand the performance of gas detector installation locations, specifically looking at (1) the role that detector location plays in detecting leaks before certain hazardous conditions arise and (2) the ability for the detector to provide sufficient response time prior to any hazardous conditions arising. The study highlights the importance of requiring a gas detector in the same room as permanently installed fuel-gas appliances. For these detectors, generally better performance was observed when: the detector was placed closer to the leak source, there was an unobstructed path between the detector and the leak source, and when the detector alarm threshold was lower (i.e., 10% Lower Flammability Limit (LFL) compared to 25% LFL). Poorer performance was observed when a detector was located: near HVAC supply registers; near passive openings such as doors and windows; and near openings to adjacent areas (e.g., door openings and stairwells). The final report describing the entire study can be found on the hazardous materials page under gases. To learn more about dozens of Fire Protection Research Foundation projects currently underway, click here.
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Request for Proposals are now open for three FPRF research projects

Request for Proposals are now open for three Fire Protection Research Foundation (FPRF) research projects. First Responder Small Unmanned Aerial Systems (sUAS) Operations Training: Baseline Materials & Usage Assessment: The overall goal of this project is to substantially increase the availability of free training and education on the safe implementation and utilization of small unmanned aerial systems (sUAS) used by the Public Safety Departments. This RFP specifically addresses the role and related details of the FPRF contractor for developing baseline content and materials that include assessment of current and trending knowledge, policies, and standards on public safety drone usage and collect relevant public safety drone usage and application information. The deadline for submitting proposal is 5 pm ET on 10 March 2020. Economic and Emotional Impact of an Active Shooter / Hostile Events: The overall project goal is to establish a sustainable quantitative approach to identify and measure the economic and emotional impact of events that are addressed by NFPA 3000, Standard for an Active Shooter / Hostile Event Response (ASHER) Program. The overall objectives are: (1) Establish valid economic measures for emergency responders; (2) Quantify short- and long-term emotional impact on emergency responders; and (3) Justify resources needed for preparedness, training, equipment, & other critical needs. The deadline for submitting proposal is 5 pm ET on 13 March 2020. Occupational Exposure of Firefighters – A Literature Review: The goal of this project is to review existing research into firefighter exposure and identify all the potential contaminants that firefighters can be exposed, depending on the type of fire attended. The deadline for submitting proposal is 5 pm ET on 16 March 2020. You can also find all three RFPs on the Foundation website.
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Transition in the Refrigeration Industry Will Have an Impact on Emergency Response

  The ongoing push toward sustainability of refrigeration systems requires the adoption of low global warming potential (GWP) refrigerants to meet the shift in environmental regulations. In 2016, nearly 200 countries signed the Kigali Agreement, a legally binding accord focused on the reduction of hydrofluorocarbons (HFCs) - the hydrogen, carbon, fluorine based compound that is commonly used in refrigerators and air conditioners. The new class of replacement refrigerants pose various hazards including increased flammability risks. As new refrigerants are phased in, there are new hazards that emergency responders need to be aware of in order to adjust response tactics. It is essential that emergency response and preparedness is emphasized during the transitional process and that firefighters and others are familiar with the change in material hazards and appropriate response procedures. The Fire Protection Research Foundation (Research Foundation), the research arm of NFPA, collaborated with NFPA on a two-year research project on flammable refrigerants. Funded by an Assistance to Firefighter Grant from FEMA, the goal of the project was to enhance firefighter safety and reduce potential injury by providing training on the hazards that may exist in appliances with flammable refrigerants. More specifically, the objective was to document key information about the technology and potential hazards so that information could be shared via interactive training modules that include classroom sessions, online learning, and educational videos for the fire service. As part of this research initiative, the Research Foundation facilitated a workshop in September 2018 with industry stakeholders and members of the fire service. The risks that firefighters will be exposed to during a call involving flammable refrigerants were discussed, and brainstorming about the content and materials needed to inform audiences took place. One clear takeaway was that although firefighting is an inherently dangerous profession, emergency responders need to be trained and educated on the shift in refrigerant materials in order to appropriately adjust tactics and keep safe. Participants also expressed concerns about the products of combustion, and recommended that possible symptoms for exposure during and after an incident be clarified; and that the adequacy of PPE and post-event de-contamination strategies be addressed. Workshop proceedings can be found here. In May of this year, The Research Foundation published another report documenting the hazards associated with flammable refrigerant technologies. That document contains the results of a literature review, consisting of flammable refrigerants baseline information, existing product usage details, new implementation considerations, potential integration into future technologies, and current response and tactics guidance. Additionally, researchers looked at the current and potential use cases for refrigerants, the various applications in which they are employed, the types of environments in which they might be encountered, and a range of associated threats. These hazards must be balanced against their performance for specific applications, including toxic thermal decomposition, combustion products, increased flammability, explosion risks, and pressure release scenarios. The report also identified a few existing knowledge gaps, specifically that fire service personnel are not well-versed on the evolving hazards associated with new flammable refrigerants. Although the potential production of hydrogen fluoride and other toxic thermal degradation byproducts exists for all halocarbon refrigerants, further investigation is needed to determine the difference in the toxic quantities produced by existing refrigerants versus the new refrigerants. To date, the variations in hazards have not been completely defined - most likely because the standards governing refrigerant charges are still under review. The gap analysis was intended to inform new NFPA training for the fire service which will debut later this year to assist first responders in recognition, evaluation, and mitigation of any flammable refrigerant related hazards. As part of this research, demonstrative tests were also conducted to support the development of these training materials. The transition to this new class of refrigerants is already underway and being led by the countries that signed on to the Kigali Agreement. Thus, it is critical that firefighters and others are aware of the potential fire hazards that may occur in various applications such as retail food refrigeration units or air conditioning systems. More information on the NFPA and the Research Foundation resources on this topic is available at www.nfpa.org/refrigerants.

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