Similarly, [if] someone left Jerusalem and remembered that he had sacrificial meat in his hand —- if he has passed Tzofim, he burns it where he is; but if not, he [must] return and burn it before the Temple with the wood of the [altar] pyre.  And for how much [chametz or meat] must they return? — R' Meir says: In either case, [when there is] as much as an egg; R' Yehudah says: In either case, [when there is] as much as an olive. but the Sages say: [For] sacrificial meat, as much as an olive, but [for] chametz, as much as an egg.

Where it is customary to do work on the eve of Pesach until midday, we may do [work], [but] where it is customary not to do [work], we may not do [work].  [If] one goes from where they do [work] to where they do not, or from where they do not to where they do, we lay upon him the stringencies of the place which he has left and the stringencies of the place to which he has gone. But let no man deviate [from local custom], to avoid conflict.