Process Safety and Environmental Protection 145 (2021) 203–210 Contents lists available at ScienceDirect Process Safety and Environmental Protection journal h om epage: www.elsevier.com/locate/psep Experimental investigation of small-scale CS 2 (carbon disulphide) pool fires Saumitra Mishra ∗ , Pushpendra Kumar Vishwakarma, Ankit Sharma, Kirti Bhushan Mishra ∗ Technological Risk Research and Analysis Group (TRAG), Department of Mechanical and Industrial Engineering, Indian Institute of Technology Roorkee, Roorkee, 247667, Uttarakhand, India a r t i c l e i n f o Article history: Received 14 May 2020 Received in revised form 3 August 2020 Accepted 3 August 2020 Available online 7 August 2020 Keywords: Carbon disulphide Pool fire Mass burning rate Thermal radiation SO2 exposure a b s t r a c t This work reports the characteristics of CS 2 pool fires such as Mass Burning Rate (MBR), flame length, flame temperature, concentration of combustion products (CO 2 and SO 2 ) measured for two pool diameters (d =0.05 m and 0.1 m) in the laboratory scale test setup and with well calibrated instruments. Mea- surements indicate that the MBR of CS 2 pool fires (d ≤ 0.1 m) is governed mainly by conduction and convection like hydrocarbons and decrease with an increase in diameter. For d =0.05 m the MBR of CS 2 pool fires are 1.5 times higher than gasoline. Due to convection, at d =0.1 m, the MBR of CS 2 pool fire was similar to gasoline but 1.5 times higher than diesel and ethanol. Depending on the background CS 2 flames are invisible (in daylight) and whitish blue (in dark environment) having shorter flames with neg- ligible thermal radiation in comparison to diesel, gasoline and ethanol. Emission measurements revealed that even for a very short duration (60–120 s) burning of CS 2 pool fire produced higher concentration (>200 ppm) of SO 2 as prescribed by the National Institute for Occupational Safety and Health (NIOSH) for Immediate Dangerous to Life and Health (IDLH). A correlation among pool diameter, time of burning and concentration of SO 2 is developed, which can be used to assess the fire risks associated with the processing, storage and transportation of CS 2 . © 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved. 1. Introduction Carbon Disulphide (CS 2 ) is a highly flammable and toxic liquid which is generally used as solvents in chemical industries. Due to its wide flammability limits (1%–50% by volume), it poses great fire threat once leaked from a container. The leaked fuel may form a liquid pool and produce pool/spill fire after ignition. CS 2 burning as faintly-luminous diffusion flames makes their detection (unless SO 2 detector is used) and suppression difficult. Apart from carbon dioxide (CO 2 ), CS 2 fires also emit sulphur dioxide (SO 2 ), which is one of the major environmental air pollutants. The continuously increasing usage of CS 2 in various industries (cosmetics, furni- ture, agriculture, insecticides, and textiles) (Guerra et al., 2018; Mukherjee et al., 2007) implied their safe storage and transporta- tion from potential fire and explosion incidents. The physical and chemical properties of CS 2 are illustrated in Table 1. Due to its low auto-ignition temperature, high volatility and low flash point, CS 2 ∗ Corresponding authors. E-mail addresses: mishra.saumitra13@gmail.com (S. Mishra), Kirti.mishra@me.iitr.ac.in (K.B. Mishra). may lead to a severe explosion and fire hazard. One such incident was reported in India, where the CS 2 explosion caused the death of a worker (“Hindustan Insecticides staffer dies after carbon disulphide leak,” 2016). The inherently toxic fluid CS 2 releases CO 2 and SO 2 as main combustion products which are harmful to human lives along with adverse effect on the atmosphere. Complete or incomplete combustion of CS 2 may prove disastrous due to following reasons: (a) Most of the fire detectors work on the principle of either smoke detection or radiative heat flux. CS 2 flame produces negligible smoke, is relatively non-luminous in nature that shows lower emissivity “” and therefore results in lower radiation from flame. Also, a transparent or less visible flame is difficult to detect with human eyes too making it disastrous in sudden outbreak cases. (b) SO 2 is the primary poisonous emission product as a result of CS 2 burning. Even the short (10 min. for 30 ppm of SO 2 (Gardner et al., 2010)) time exposure of the same can prove to be a lethal dose for the nearby inhabitants. The incapacitation of plant personnel due to excessive inhalation of SO 2 coming from CS 2 burning can also obstruct the early control and mitigation measures. https://doi.org/10.1016/j.psep.2020.08.002 0957-5820/© 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.