Revealing the components and thermal hazard characteristics of traditional spark and cold light fireworks

Abstract

Taiwan’s pyrotechnics regulations cover nine categories, ranking spark-type fireworks as the third most substantial group. These fireworks, which are broadly used in festivals and public events, include professional stage pyrotechnics (cold light fireworks) and normal spark light fireworks, which share a similar discharge pattern. The difference lies in the temperature they generate when burning and the temperature required for ignition. Cold light fireworks generate an average of 201.49 °C, whereas normal spark light fireworks reach 503.38 °C. This temperature disparity results from the composition differences, with cold light fireworks containing nitrocellulose, which has higher energy and nitrating properties. Their average enthalpy (ΔH_d) is 2389.64 J g^‒1, compared to 567.42 J g^‒1 for normal spark light fireworks, raising safety concerns. The study used commercially available fireworks, minimising sample contamination by excluding certain fixtures. Thermal parameters and apparent activation energy were used by simultaneous thermogravimetric analysis and the Flynn–Wall–Ozawa, Friedman, and ASTM E698 thermokinetic analysis revealed that the temperature of sparks of cold light fireworks appears harmless to the human body on the surface. The lower apparent activation energy and higher heat release show their potential harm.