Below is an extract from the Florida Building Code (2017 edition)

SECTION2407
GLASS IN HANDRAILS AND GUARDS

2407.1 Materials.

Glass used in a handrail, guardrail or a guard section shall be laminated glass constructed of fully tempered or heat-strengthened glass <...>.

Glazing in railing in-fill panels shall be of an approved safety glazing material that conforms to the provisions of Section 2406.1.1. <...>

Exception: Single fully tempered glass <...> shall be permitted to be used in handrails and guardrails where there is no walking surface beneath them or the walking surface is permanently protected from the risk of falling glass.