For the Hydro test.
Safe distance = (0.15)x(D)x(a)^0.4x(p)^0.6
where D – Internal diameter (m)
a – Length/diameter of piece (m)
p – Test pressure (bar)
For fluids (3.3) it is :
l = 0.15 x internal diameter x ((alpha) ^ 0.4) x ((test pressure / (cube
root of density))^ 0.6
For gases (4.3) it is :
l = 30; 3.6 x cube root of (volume x ((test pressure + length) – ((test
pressure + length) ^ 0.714)))
where D – Internal diameter (m)
A – Length/diameter of the piece (m)
P – Test pressure (bar)