How should cleaning clearance be specified for commercial heating elements?

Cleaning clearance between commercial heating elements must be set from the real duty, not a catalogue figure. Establish tube diameter, arrangement (in-line or staggered) and the narrowest gap, then have operators pass the actual brushes, spray lance or dedicated tools through it; full, unobstructed access across every sheath surface is the pass criterion. Tight spacing traps residue and scale, lengthens downtime and can cause local overheating. Record minimum gap, verified passage and tolerance on the drawing, and cross-check them against power, watt density, sheath material, ingress protection and control conditions, verifying both cold and hot states after installation.