OCLC has an institutional registry , which had (in part) library hours, addresses, and so forth. It seems to be unavailable, though . That is the only systematic collection of library hours data that I know about.
> On May 5, 2015, at 4:16 PM, Bigwood, David <[log in to unmask]> wrote:
> This looks like a decent group, but I find this statement hard to believe.
> "Your tax-deductible donation supports adding the names, address and the hours of operation of all libraries to Range. The Institute of Museum and Library Services publishes an open data catalog which is the source we'll use for the names and the addresses of the nation's libraries. However, there isn't a listing of the days and hours of operation for all libraries in the US. We are going to track down the hours of operation for all 17,000 libraries and make that information available -- in Range and for other developers who may want to use it." https://www.indiegogo.com/projects/range-food-and-safe-places-for-youth
> Are the hours of public libraries really not available?
> David Bigwood
> [log in to unmask]<mailto:[log in to unmask]>
> Lunar and Planetary Institute