Valve accessibility and clearance distance

While doing layout of a plant we need to provide access to valves for operating and maintenance. Here we will list out the distances need to be maintained for the same:

1. For vertical stem valves:

 Vertical distance from Grade to valve handles top edge – 1100mm to 1300mm

                          2^nd choice acceptable- 600 mm to 1100mm

Valves can be placed over access area with chain pulley -minimum head clearance needed – 2200 mm 

2. For horizontal stem valves:

 Vertical distance from Grade to valve handles centre line – 1100mm to 1400mm

                           2^nd choice acceptable- 600 mm to 1100mm

                   Valve chain wheel height approx – 900mm

   Valve distance to be maintained if from outside grating – 500 mm

   Minimum width of access way for maintenance of valve- 1070 mm  

2. Clear headroom:

Clear headroom under structure/piping inside operating area – 2200 mm