Identification and characterization of design fires and particle emissions to be used in performance‐based fire design of nuclear facilities

Abstract

Summary CERN operates one of the most complex particle accelerator facilities in the world. Several different hazards, including fires, are present and need to be investigated and reduced to a tolerable level. Toward this goal, CERN aims at developing a catalog containing detailed fire dynamics descriptions of combustible items present in its facilities. This paper contributes to this catalog in two ways. First, through the development of a design fire calculator for electrical cabinets that allows the determination of potential design fire curves for any number of electrical cabinets/racks. The second contribution was to experimentally characterize the smoke production rates and smoke particle properties of the most common cables and insulating oils used at CERN by coupling a fast particle mobility analyzer to a cone calorimeter. The two particle size modes (accumulation and nucleation mode) could be linked to the fire properties and heat release rate. Accumulation mode particles (~200 nm) were associated with high heat release rates and high soot emissions from the flame. This study identifies a necessity to consider ultrafine particle emissions with low mass emissions but high number emissions in relation to risk assessments pertaining to nuclear facilities and dispersion of radioactive aerosols to the surrounding environment.

Simulation and design research on improving MPASS based on dual-wavelength detection technology

“…In the early fire, combustibles generally release smoke in the stages of pyrolysis and smoldering 1 . Therefore, smoke detectors exhibit faster responses to fires when compared to other types of fire detectors that detect flames, heat, and gases 2 .…”

Size Distributions of Inhalable Particulate Matter and Particle-bound Heavy Metals and Their Potential Occupational Health Risk Related to Informal E-waste Recycling in Thailand

“…It was reported that size distribution of particles obtained from thermal cutting of metals was associated with cutting parameters such as cutting materials, cutting methods, cutting conditions [15,16]. Many studies revealed that open burning of insulated copper wire and electronic waste released small particles, PAHs and heavy metals into the atmosphere [17][18][19]. Several findings reported that concentrations of atmospheric particle-bound heavy metals in e-waste recycling areas were significantly higher than those in uncontaminated areas [11,12,[20][21][22].…”