Investigation into the toxicity of combustion products for CR/EPR cables based on aging period

Seo, Hyun Jeong; Kim, Nam Kyun; Lee, Min Chul; Lee, Sang Kyu; Moon, Young Seob

doi:10.1007/s12206-020-0340-z

Cited by 14 publications

(11 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The TG analyzer is a useful tool for analyzing the thermal decomposition and pyrolysis of materials using TG and differential thermal analyses according to the heating rate [20][21][22][23].…”

Section: Accelerated Aging Methodsmentioning

confidence: 99%

Influence of Thermal Aging on the Combustion Characteristics of Cables in Nuclear Power Plants

et al. 2021

Self Cite

View full text Add to dashboard Cite

In this study, the combustion characteristics and emission of toxic gases of a non-class 1E cable in a nuclear power plant were investigated with respect to the aging period. A thermal accelerated aging method was applied using the Arrhenius equation with the activation energy of the cables and the aging periods of the cables set to zero, 10, 20, 30 and 40 years old by considering the lifetime of a nuclear power plant. According to ISO 5660-1 and ISO 19702, the cone calorimeter Fourier transform infrared spectroscopy test was performed to analyze the combustion characteristics and emission toxicity. In addition, scanning electron microscopy and an energy dispersive X-ray spectrometer were used to examine the change in the surface of the sheath and insulation of the cables according to the aging periods. To compare quantitative fire risks at an early period, the fire performance index (FPI) and fire growth index (FGI) are derived from the test results of the ignition time, peak heat release rate (PHRR) and time to PHRR (tPHRR). When comparing FPI and FGI, the fire risks decreased as the aging period increased, which means that early fire risks may be alleviated through the devolatilization of both the sheath and insulation of the cables. However, when comparing heat release and mass loss, which represent the fire risk at the mid and late period, fire intensity and severity increased with the aging period. The emission of toxic gases coincided with the results obtained from the heat release rate, which confirms that the toxicity of non-aged cables is higher than that of aged cables. From the results, it can be concluded that the aging period significantly affects both the combustion characteristics and toxicity of the emission gas. Therefore, cable degradation with aging should be considered when setting up reinforced safety codes and standards for cables and planning proper operation procedures for nuclear power plants.

show abstract

Section: Accelerated Aging Methodsmentioning

confidence: 99%

Influence of Thermal Aging on the Combustion Characteristics of Cables in Nuclear Power Plants

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…Figure 10 shows the evolution of gas emissions during external flux testing in the range of 25 to 50 kW m −2 . The consumption of O 2 exhibited a trend of first decreasing and subsequently increasing with the increase of time, and the production of CO 2 [ 31 ] exhibited a trend of first increasing and subsequently decreasing. The time to reach the peak is similar to the time to reach pHRR.…”

Section: Resultsmentioning

confidence: 99%

Effect of the Current on the Fire Characteristics of Overloaded Polyvinyl Chloride Copper Wires

Li¹,

Qin

Li³

et al. 2022

Polymers

View full text Add to dashboard Cite

In this study, the fire behavior variation of unenergized polyvinyl chloride (PVC) copper wires subjected to overload with different currents was investigated by a cone calorimeter. Overload currents were selected from 1 times safe-rated current (Ie) to 3.5 times Ie to obtain tested sample wires. The mass fraction, time to ignition (TTI), heat release rate (HRR), gas emission, and residue were measured. If the current flowing through the wire increased up to 3.5 times Ie, the TTI of this unenergized wire increased drastically and the peak HRR (pHRR) decreased notably so that the flame growing index (FGI) reduced considerably. When the wire carried less than three times Ie, the FGI remained stable. For all overloaded PVC copper wires, the increase in the heat flux resulted in a higher pHRR and a lower burning duration. However, regardless of the external heat flux exposure, the FGI of copper wires overloaded at 3.5 times Ie was lower than that of copper wires carrying less than other times Ie. Moreover, the consumption of O2 and generation of CO2 as the heat flux varied were consistent with that of the HRR. Opposed to expectation, the flame propagation of unenergized PVC copper wires would decline in a fire, if the wire has been damaged by overload with some currents.

show abstract

“…It is important to more comprehensively evaluate the fire risk of cables installed in utility tunnels, as overloading of cables represents the main cause of fires in utility tunnels. In addition to disrupting a city's communication network and power supply, cable fires also generate toxic gases from the burning of the cable sheath, which interfere with firefighting activities [9,10]. These harmful gases are also released to the outside through ventilation, which may harm local residents.…”

Section: Introductionmentioning

confidence: 99%

“…Despite these risks, there are currently no specific evaluation criteria for the fire risk of cables installed in utility tunnels. The existing fire-retardant performance regulations of cables stipulates that they cannot be used below a certain performance level, which is ascertained by conducting a fire-retardant performance evaluation test [9][10][11]. However, when only the performance level is used as a criterion, only the flame is considered, so such an evaluation is limited by not considering all the risk factors of a cable fire.…”

Section: Introductionmentioning

confidence: 99%

An Experimental Study for Deriving Fire Risk Evaluation Factors for Cables in Utility Tunnels

Seo,

Chung,

Song

2023

Fire

Self Cite

View full text Add to dashboard Cite

In this study, we performed three tests to measure the fire-retardant performance of power cables installed in utility tunnels. The standards we applied for testing are ISO 5660-1, NES 713, and IEEE 1202. Specifically, we performed a cone calorimetric analysis, calculated the toxicity index, and measured the flame spread length on material surfaces. Even though the same fire-retardant chemical composites were applied, various differences in fire-retardant performance were found depending on the chemical properties of the cable sheath and insulation. We also found that gaseous substances generated during the burning of cables can serve as important risk assessment factors in fires. We determined that, in addition to the heat generated when the cable burns, the toxic gases emitted at this time can also be a risk factor. This is because it is important to consider any potential risk to a person entering as part of an initial response to an event or accident involving cables installed in utility tunnels. Moreover, in the event of a fire in the cable, there is a risk of hazardous substances flowing into the city center as toxic gases are released. Therefore, we determined that the risk of hazardous gases emitted during cable fire should be reflected in the fire-retardant performance standard.

show abstract

Investigation into the toxicity of combustion products for CR/EPR cables based on aging period

Cited by 14 publications

References 19 publications

Influence of Thermal Aging on the Combustion Characteristics of Cables in Nuclear Power Plants

Influence of Thermal Aging on the Combustion Characteristics of Cables in Nuclear Power Plants

Effect of the Current on the Fire Characteristics of Overloaded Polyvinyl Chloride Copper Wires

An Experimental Study for Deriving Fire Risk Evaluation Factors for Cables in Utility Tunnels

Contact Info

Product

Resources

About