Choosing the right steel cover

Although BS EN 124 does cover manhole tops manufactured from a variety of materials including steel it is argued that some test procedures are inappropriate for steel. The standard defines certain test loads and minimum permanent deflections that are impractical from an economic point of view and it is maintained are unnecessary in certain slow-moving traffic situations. In addition, steel fabrication is a highly flexible process allowing all sorts of non-standard sizes and designs that are not covered by BS EN 124.

As a consequence, the industry in the UK uses a number of definitions of loading categorisation that can be confusing. Some are historical descriptions while others are descriptions based on the gross laden weight of a vehicle or individual wheel loads. There can be conflicting definitions of exactly what the descriptions mean and how the access cover will perform.

In an attempt to apply some logic and give guidance to users the Fabricated Access Covers Trade Association (FACTA) of which Wrekin is a member has produced definitions and loading categorisations in the form of classes for fabricated covers but not pressed tops.

In addition many of the historical loading descriptions still persist so using our 30 years experience and technical knowledge Wrekin have produced a guide to load categorisations and the correct choice of Wrekin product.

Key points

• Where steel products are suitable for use in vehicle situations they are designed for slow moving traffic applications only (up to a maximum of 20MPH). They must never be used in highways or any other area of fast moving traffic.
• Access covers manufactured from pressed steel are recommended only for areas of low intensity traffic.
• None of the loading categorisations can be directly compared to BS EN 124

Internal and external areas which can only be used by pedestrians or bicycles e.g. toilets, changing rooms, footpaths, cycle paths.

Very light industrial areas, where small trolleys and cars/small vans can manoeuvre e.g. domestic driveways, trolley parks and hospital wards.

Service areas, shopping centres and light industrial areas.

Light industrial areas where trolleys and light pallet trucks operate.

Pneumatic tyres

Pedestrian precincts, light commercial delivery or parking areas.

Solid tyres

Factories, industrial plants where small pallet trucks operate.

Pneumatic tyres

Factories, industrial plants, commercial delivery or parking areas.

Solid tyres

Industrial areas where pallet and small fork-lift trucks operate

Pneumatic tyres

Heavy duty plant areas and service roads where HGV's can reach speeds of 20mph max.

Solid tyres

Heavy duty industrial areas where medium duty fork-lift trucks operate.

Pneumatic tyres

Dockside and container storage areas where heavy duty transporters operate.

Solid tyres

Very heavy industrial areas where large heavy duty fork-lift trucks operate.

Pneumatic tyres

Airfield aprons where particularly heavy wheel loads are imposed by aircraft and towing vehicles.

Never use steel covers in any highway situation due to traffic speed and intensity. Use Wrekin ductile iron covers in this situation.