How to choose a manhole cover

For the success of a project, it is important to know how to choose the right manhole cover, made of PVC, concrete or other material. The manhole cover must always be in the class appropriate to the place of installation and therefore to the stress it will be subject to. If in doubt you must use a device of a stronger class than that strictly foreseen.

The designer must also choose a size appropriate for the clearance to guarantee safe access to the manhole cover with manhole. As far as the shape is concerned, generally the Italian market of grids and underground works have the widespread presence of square shapes (starting from the outside dimension of the 300×300 frame), rectangular and circular shapes. Fuel service stations and purifying plants have manhole covers with outside dimensions exceeding 1 m.

Furthermore, before installation, the following indications must be checked:

• the manhole cover must be appropriately marked with reference to the standard (EN124) and to the certification body which issued the certification marking;
• manhole cover – manhole are to be understood as a single item, in that the former is to be installed above the latter. The frame of the manhole cover must therefore have the same shape as the device underneath;
• the height of the frame must be less than or equal to the depth of the housing so that, when the job is done, the frame, cover and paving are flush. It is preferable that the depth of the housing chamber be 2 to 4 cm higher than the frame to be able to make a concrete bedding which guarantees correct distribution of the loads on the support surface.

KIO Composite Manhole Covers                            Discover the features of manhole covers