Tohoros 3:4-5

Tohoros 3:4

If food the volume of an egg was left in the sun so that it reduced in size – and the same is true of an olive’s volume of a corpse, an olive’s volume of carrion, a lentil’s volume of vermin, an olive’s volume of piggul (a sacrifice offered with improper intentions), an olive’s volume of nosar (a sacrifice left over past its time) or an olive’s volume of prohibited fat – they become clean and one isn’t liable for piggul, nosar or prohibited fat because of them. If these things were left in the rain so that they swelled back up to their original volumes, they become unclean again and one is liable for piggul, nosar or prohibited fat because of them.

Tohoros 3:5

All cases of impurity are based upon the status quo as of the time they were found. If they were found unclean, they are presumed to have been unclean; if clean, they are presumed to have been clean. If they were found covered, they are presumed to have been covered; if uncovered, they are presumed to have been uncovered. If a needle was found rusty or broken, it is ritually clean because all cases of impurity are based upon the status quo as of the time they were found.