A room with a doorway was by the portico in each of the inner gateways, where the burnt offerings were washed.
References for Ezekiel 40:38
In the portico of the gateway were two tables on each side, on which the burnt offerings, sin offerings and guilt offerings were slaughtered.
References for Ezekiel 40:39
By the outside wall of the portico of the gateway, near the steps at the entrance of the north gateway were two tables, and on the other side of the steps were two tables.
So there were four tables on one side of the gateway and four on the other—eight tables in all—on which the sacrifices were slaughtered.
There were also four tables of dressed stone for the burnt offerings, each a cubit and a half long, a cubit and a half wide and a cubit high. On them were placed the utensils for slaughtering the burnt offerings and the other sacrifices.
References for Ezekiel 40:42
And double-pronged hooks, each a handbreadth long, were attached to the wall all around. The tables were for the flesh of the offerings.
References for Ezekiel 40:43