Florida has one of the highest rates of childhood drowning in the country, which is part of why pool barrier requirements are not treated as optional or something you can put off. If you are installing a pool, replacing a fence around an existing one, or just building a fence anywhere on your property, there is more permitting involved than most homeowners expect.
Florida's Residential Swimming Pool Safety Act requires every new residential pool to have at least one layer of protection to prevent unsupervised access by young children. This is not a suggestion from your HOA. It is state law, and it gets verified as part of the permitting and inspection process before a pool can legally pass final inspection.
You do not have to pick a fence specifically. The law allows several approaches, and many homeowners combine more than one:
Whichever combination you choose, the inspector is checking it against the approved plans submitted with your pool permit, not just eyeballing it on-site.
Separate from pool safety, most Florida jurisdictions require a permit to install or replace a fence above a certain height, and some require it regardless of height once it exceeds a short run of linear footage. This surprises a lot of homeowners who assume a fence is a weekend project that does not involve the building department at all.
Permit review for a standalone fence typically checks setback from the property line, height limits for the zoning district, and whether it is within a flood zone or easement that affects placement. If the fence is doubling as a pool barrier, it also has to meet the stricter pool safety specifications above, not just general fence code.
That last one catches people off guard. A county permit does not override your HOA's architectural review requirements, and plenty of HOAs require sign-off on fence style, material, and color before work starts.
If you are building a pool, the barrier is not an afterthought, it is part of what gets your permit closed out. If you are just replacing an old fence, check with your building department before you assume it is permit-free, and check with your HOA separately. A fence that passes county inspection but violates your HOA's rules is still a problem you will have to deal with.