Chaining your dog should be a last resort. But if you must, your dog can only be chained to a fixed object for up to 2 hours per 12 hour period. If you use some type of running line, pulley or trolley system then your dog may be tethered for up to 4 hours per 12 hour period. Keep in mind that the dog should be able to access food, water, shade, and shelter as well.