Two “judge instead of referee” posts in a single day… please realize that judges and referees are two different groups of people. Judges don’t care about horns (or safety glasses) unless you document it in your engineering notebook. The extra work to do the horn would be an interesting page in the EN for the Judges if you documented it. Referees are the officials who would make the call on a nonfunctional decoration (the horn) or decide if true “safety glasses” are required, or if standard eyewear is sufficient (it can vary at every event, especially local/regional events). Getting used to wearing safety glasses is good experience: in industry, we always wear safety glasses in the shop/factory.