A user-centred assessment of a less-lethal launcher: the case of the FN 303® in a high-pressure setting

Ergonomics. 2019 Sep;62(9):1162-1174. doi: 10.1080/00140139.2019.1626916. Epub 2019 Jun 18.


The present study explored the usability of a less-lethal launcher from the end-user's perspective. A within-subjects field experiment (N = 16) tested the FN 303® in a lab condition, enabling optimal firing conditions and in a high-pressure simulated operational condition (SOC). Results showed that the high-pressure SOC, which was both psychologically and physiologically challenging, provoked significantly more subjective workload and substantial increases in cortisol biomarker secretion. Importantly, the SOC had a deleterious effect on participants' shooting accuracy at a static target at 30 m. Moreover, as might be expected, accuracy was affected, notably in the hazardous vertical y-axis. Finally, the SOC significantly influenced participants' perception of the overall usability of the FN 303®. These findings, combined with reduced accuracy, could become critical factors during real-life crowd control operations. To the authors' knowledge, no empirical work has tested less-lethal launchers from an end-user's perspective. Recommendations are made with regard to the selection, training, skill maintenance, and design.

Keywords: Cortisol; crowd control; less-lethal launcher; usability; workload.

MeSH terms

  • Adult
  • Biomarkers / analysis
  • Computer Simulation
  • Firearms*
  • Humans
  • Hydrocortisone / analysis
  • Male
  • Military Personnel / psychology*
  • Work / physiology*
  • Work / psychology*
  • Workload / psychology*
  • Young Adult


  • Biomarkers
  • Hydrocortisone