Looking through the NEC, I see requirements for protection from physical damage in specific locations (agricultural buildings, hazardous classified locations, indoor sports facilities, etc.), but I don't see anything specific to residential installations, or residential garages.
I don't see how 410.11 would apply to a fluorescent luminaire in a residential garage. This section is intended to prevent "combustible material" around the luminaire from getting hot enough to burst into flames. If the outside of your fluorescent strip light is hot enough to make something near it spontaneously combust, you've got bigger problems.
410.12 only applies to "lampholders installed over highly combustible material." I think it's a bit of a stretch to say that a luminaire installed in a residential garage is "over highly combustible material." Yes, gasoline is very combustible, but it's pretty rare for somebody to store an open bucket of gasoline in their garage. Gasoline inside a gas can or a vehicle's gas tank is pretty stable, and is not in much danger of being ignited by the light on the garage ceiling. There are LOTS of houses out there with exposed fluorescent strip lights installed in the garage -- there have been for years -- and have you ever heard of a fire or an explosion caused by those lights lacking a lens or wire guard? I haven't.
There's certainly nothing wrong with installing lensed fixtures in a garage, but as far as I can tell it's not an NEC requirement.