A fixed vertical ladder provides permanent access to elevated equipment, tanks, platforms, and roofs — fabricated from two parallel SS stringers (side rails, typically flat bar 60×8 mm or channel 60×30 mm) connected by horizontal SS rungs (round bar Ø25–Ø32 mm at 225–300 mm vertical centres) welded or swaged in position. Heights from 1,000 mm to 12,000+ mm; width of 400–600 mm clear rung width. For heights above 3,000 mm (EN ISO 14122-4 requirement), a safety cage (hooped cage: hoops at 900 mm centres, vertical bars at 300 mm centres) is added around the climb path — forming a cage ladder. Above 6,000 mm, rest platforms are required at maximum 6,000 mm intervals within the cage.

Stringers are fixed to wall, vessel shell, or structural steelwork using adjustable standoff brackets at 1,800–2,000 mm centres — brackets allow ±50 mm adjustment for alignment and thermal movement. Rungs are welded to stringers at equal centres (225 mm for GMP/pharma; 300 mm for industrial) with a minimum 150 mm clearance between rung back face and structure. For cage ladders, hoops (Ø600–680 mm inner clear diameter, fabricated from 32×6 mm flat bar bent to radius) are welded to vertical cage bars at 900 mm vertical centres. The cage extends from 2,200 mm above landing level to the top of the ladder — at the ladder top, a swing-over safety hatch or step-through opening provides access to the platform. A personal fall arrest rail (vertical lifeline) can be specified as an alternative to a cage for slimmer installation.