## 5 Conclusions  
Within the laboratory setting, H-C scaling enabled reasonable predictions of blast parameters at different scales. Lab-scale limitations prevented exact geometric similarity between different-scale experiments. However, despite this limitation, the blast profile during the initial positive phase appeared to scale well for gauges B1 and B2. These locations were shielded by the corner and were not affected by the blast wave wrapping around the other side of the structure. Notably, nearly identical profiles were observed between the two different scales at these gauges. Comparisons were made between the laboratory setup and field trials [11] that featured a similar arrangement. The experimental geometry of the structure in the laboratory setup exhibited half symmetric, and simulations showed that only gauge B3 (located farthest from the explosive and nearest to the back wall) would be affected by this symmetry condition. As predicted by numerical models, the positive phase duration experimental results for B3 were longer than in the field tests. Despite this, the B gauges showed a good correlation between the laboratory-predicted values (using H-C scaling) and the field tests for the time of arrival and incident overpressure. Larger variations were found for the positive phase duration and impulse. In the field tests, a reflective pressure wave was observed as the initial pressure wave decayed. This phenomenon, which was not observed in the laboratory experiments, resulted in a longer positive phase duration and a higher cumulative impulse. At gauge  
Figure 16: Overpressure\(-\)time histories and cumulative specific impulse for B1 between t = 1.5 and 4.5 ms.  
A, the laboratory results were used to reasonably predict incident overpressure, positive phase duration, and impulse. However, the time of arrival in the laboratory experiments was significantly shorter because different explosive materials were used in the two test scenarios. This is the first study of its kind to show the interscalability of laboratory experiments relevant to urban blast scenarios and compare the findings to field trials conducted elsewhere. It shows that it is possible to address the challenges and complexities associated with urban blast-loading scenarios using this approach. These findings have the potential to contribute to the development of comprehensive guidelines for blast protection design in urban environments. Additionally, they can aid in the modelling of blast injury risk in urban environments, enabling the assessment of potential injuries that medical personnel may encounter in specific areas. The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/app13105956/s1](https://www.mdpi.com/article/10.3390/app13105956/s1)]([https://www.mdpi.com/article/10.3390/app13105956/s1](https://www.mdpi.com/article/10.3390/app13105956/s1)). Conceptualisation, J.D. and G.S.L. ; methodology, J.D., S.G., S.C.K.Y. and R.A.G. ; software, J.D. ; validation, S.G. and J.D. ; formal analysis, S.G., J.D. and G.S.L. ; investigation, S.G., J.D. and S.C.K.Y. ; resources, J.D., G.S.L., R.A.G. and S.C.K.Y. ; data curation, J.D. and S.G.; writing--original draft preparation, S.G., J.D. and G.S.L. ; writing--review and editing, S.C.K.Y., R.A.G. and G.S.L. ; visualisation, J.D. and S.G.; supervision, G.S.L. and S.C.K.Y. ; project administration, J.D. and S.C.K.Y. ; funding acquisition, G.S.L., J.D. and S.C.K.Y. All authors have read and agreed to the published version of the manuscript. This research was supported by funding from the University of Cape Town Research Committee, the University of Southampton Global Partnerships Award, the Clinical Informatics Research Unit (CIRU), the University of Southampton, and the International Blast Injury Research Network (IBRN). The data for pressure histories found in the experiments were included as Supplementary Materials. The authors wish to acknowledge the Mechanical Engineering Workshop staff and [PERSON] for their assistance with the technical design.