The adduct of Urea and Hydrogen Peroxide (UHP), also called Carbamide Peroxide, is industrially produced as a solid source of hydrogen peroxide for bleaching, disinfection, and oxidation reactions. As a chemical combination of fuel and oxidiser, UHP has explosive potential but it is unclear whether it could sustain a detonation at small scale. In the configuration we tested, we succeeded in recording self‐sustained detonation at relatively small scale under heavy confinement, measuring a maximum experimental velocity of detonation of 3860 m/s at an optimum 1.1 g/cm3 loading density. UHP can sustain a detonation, even at the 100 g scale, but this is strongly dependant on booster size, confinement material, loading density, charge length and diameter. According to our performance assessment, pure UHP exhibits the behaviour of a non‐ideal tertiary explosive. Maximum calculated detonation pressures are below 10 GPa, the order of magnitude for commercial blasting explosives. Small‐scale results are consistent with literature values from large‐scale experiments, although literature on the matter is quite limited. The proposed experimental method can be used to quantify the detonability and performance of other industrial materials that may have energetic properties, or small samples of homemade explosive compositions, avoiding time‐consuming, expensive and potentially hazardous large‐scale experiments.

Carbamide Peroxide, an adduct of Urea and Hydrogen Peroxide, is commonly used in the cosmetic and pharmaceutical industries as a solid source of hydrogen peroxide. However, it exhibits explosive properties and can be easily manufactured from readily available household chemicals, making it a potential emerging threat. We carried out a detailed performance assessment, combining experiments, thermochemical calculations and numerical simulations and highlighted a good level of agreement between experimental data from lab, field and underwater firings. A maximum detonation velocity of 3.65 km/s was recorded for unconfined 25 kg UHP charges at 0.85 g/cm 3 (200 mm charge diameter). We determined in these conditions an infinite diameter detonation velocity of 3.94 km/s. These results are also consistent with previous results obtained at small scale under heavy confinement. Airblast measurements highlighted an average 40 % TNT equivalence for impulse and 55 % for peak overpressure at short distance, which are in good agreement with the 57 % (Power Index) calculated from Explo5, while 50 % for bubble energy (explosive power) and 20 % for shock pressure (brisance) were obtained from underwater experiments. The use of different experimental approaches has proven useful to characterise the performances parameters of a non-ideal explosive for risk assessment purposes. K E Y W O R D Sdetonation, non ideal explosive, performance, urea hydrogen peroxide | INTRODUCTIONCarbamide Peroxide or Urea Hydrogen Peroxide (UHP) is commonly used in the dental, cosmetic and pharmaceutical industries as a solid source of hydrogen peroxide. This adduct can also be easily manufactured from readily available household chemicals. Like other oxidisers such as ammonium perchlorate [1] or ammonium nitrate [2], UHP exhibits explosive properties [3,4] and could represent a potential emerging threat. Determining UHP detonation performance parameters is hence important for safety purposes.Because there is a need to predict large-scale explosive behaviour from small-scale experiments [5], our