The manwaydoor is located in the lower part of the tank, mostly quite on the bottom, in order to empty it completely. Indeed, it is characterised by a sturdier structure, for the purpose of supporting bigger pressures than the manhole: this means that the frame and the cover have a bigger thickness and the latch’s systems are more advanced. Sometimes the opening of the cover can be inward, in order to guarantee a biggerresistancetothestresses. The gasket of the manwaydoors is made of ethylene-propylene rubber (EPDM), but it can also be required in other materials.