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.
How to convert tons to BTU/hr. One refrigeration ton is equal to 12000 BTUs per hour: 1 RT = 12000 BTU/hr. One BTU per hour is equal to 8.33333Ã10-5 refrigeration ton: 1 BTU/hr = 8.33333Ã10-5 RT. So the power P in BTUs per hour (BTU/hr) is equal to 12000 times the power P in refrigeration tons (RT):