Depth of Water Seal (H)
[1] Effective height of water in the trap (h) which prevents the passage of foul air.
[2] The depth of water which would have to be removed from a fully charged trap before gases and odours at atmospheric pressure could pass through the trap shown as H in Figure 2.
References:
- BS EN 1253-1:2003 Gullies for buildings – Part 1
