General Guidelines for Ladders and Platforms

Types of Ladders

1)    Step Through

2)    Side Step

3)    Straight/vertical Ladder

4)    Inclined

General Guidelines

·        Platforms are provided for access to manholes, instruments, valves and equipment, and for crossovers between ladders.

·       The spacing of platforms served by a common ladder shall be in one-foot increments so as to match the rung spacing on the ladders.

·        The maximum straight run of ladder is 29'-6" from H.P.F.S. (due to grade variation).

·        Projection of nozzles extending through a top platform must be such that the flange bolts are above the platform level.

·      Avoid supporting heavy piping loads from platforms (Generally more than 500 pounds).

·      Vessel attachments, such as ladder support clips, platform support clips, vessel pipe supports, and guides are generally installed by the vessel fabricator in the shop

·       For ladder details (see the figure below), note the 7" minimum toe clearance and 15^o maximum ladder slope.

·      A ladder with and without a cage has clearance requirements that a designer needs to consider in orienting a vessel.

·      The Vessel Group will furnish a ladder and platform standard drawing for piping use

Few more Consideration

·    Platforms used effectively: LG's, TI's, PI's, SC's, PSV's, Valves, accessible from platforms if possible without making platform excessively large.

·    No side step off to a common elevation platform on both sides of ladder, unless allowed by job instructions

·      Level controller door will open 100^o without obstruction.

·      Ladders are 16" wide inside, 7" minimum toe clearance, 1'-0" maximum.

·     Centerline of ladder to edge of step off is 1'-3".

·    Platform used for step-off only at least 2'-6" wide at vessel, i.e. 1'-3" on either side of ladder going up.