The covers in Derby are usually made of metal

 

and are square

 

, oval

 

, or circular

 

in shape.

No colored or gilded covers were found in Derby, nor were any covers bearing the city emblem.

Diagonal covers were also found in Derby - square or rectangular covers composed of two triangles, opened by lifting one of the triangles

 

.

In general, the design of the covers in Derby is not unusual and follows the manufacturers’ standard designs.

In many cases it is impossible to determine the purpose of the cover. In other cases, covers marked with the letters STW belong to Severn Trent Water

 

, drainage covers are identified by their drainage slots

 

, and covers marked TRAFFIC CONTROLS are used for traffic-light infrastructure

 

.

Manufacturers
Many of the covers bear the manufacturer’s name, including Clark Drain

 

, Naylor

 

, R&B

 

, and other British manufacturers.

Standards
The most common standards are the European standard EN124

 

and its associated load classes (B125 - D400)

 

, as well as the British Kitemark standard

 

and CCIC

 

.