Why would an inspection query data.dol.gov/get/inspection/… return a 200 with an empty response?

Question

We are testing the use of the https://data.dol.gov/get/inspection/format/json/limit/100 service request and are seeing conditions where the response sometimes comes back with an empty response, but other times comes back with data. Is there additional documentation around how this API should behave? My understanding is that this call should return data consistently for each call.