1 The freezer time shown is for best quality only â foods kept constantly frozen at 0Â° F will keep safe indefinitely.  How long does baked ham last at room temperature? Bacteria grow rapidly at temperatures between 40 Â°F and 140 Â°F; baked ham should be discarded if left for more than 2 hours at room temperature.
Using this to calculate theoretical water-chilling capacity: 1 ton of refrigeration (12,000 BTUs per hour) will chill. 12,000 lbs. water/fish 1Â°F in 1 hour. Theoretically, then, a sample application to chill seawater and fish: 40 tons refrigeration (480,000 BTUs per hour) will chill. 120,000 lbs. water/fish 20Â°F in 5 hours.
Tonnage â¦ the unit of measure used in air conditioning to describe the cooling capacity of a system. One ton of cooling is based onthe amount of heat needed to melt one ton (2000 lbs.) of ice in a 24hour period. As a rule of thumb, 400 square feet can be cooled per 12,000 BTU/hr (12,000 BTU/hr equals one ton of air conditioning). However, other factors which will also affect the total heat load. â¢ Simply put, a one-ton air conditioner can remove 12,000 BTU from a space per hour.