ISO 15085 : Man overboard prevention and recovery

Hello,

Trying to design a guard rail assembly based on ISO 15085:2003.

In the section about strength requirements of stanchions or supports (Sec. 12.2.2), it says:

- A horizontal force of 280 N with a deflection under load of the stanchion or support not greater than 50 mm at the force level. If there is a clearance between the stanchions and its base, this deflection shall be measured after the stanchion is inclined enough to have no residual play, with no permanent deformation of the stanchion or support after the force has been taken off;

What does the boldfaced text mean by "clearance between stanchion and its base"? Why would there be any clearance at all? Is it referring to hinged/collapsible stanchions?

TY

 

Like this:

 

I know a picture is supposed to be worth a thousand words, but call me slow. I don't get it.

I consider the deck to be the base, ftmp. So if the hull deck is then the base and the stanchion affixed to it; how would you have a clearance?

 

My guess is "clearance between the stanchions and its base" refers to situations where the stanchion drop into hole in the base/deck, and there is clearance between to allow for the stanchion to be easily removed. For example I've seen small vehicle ferrys with stanchions which are droped into holes in the deck after the vehicles load, and the stanchions are removed for unloading.

The intent of the rule appears be to set a minimum bending strength and stiffness for the stanchions. The clearance ("play") which the rule refers to would allow the stanchion to move without bending, and if it not taken into account then a stanchion in a base with clearance/play would have to be stiffer/stronger than a stanchion fixed in the base.

 

That makes good sense DCockey.
Any kind of "residual play" in the station/base connection would result in the same situation.

Ad Hoc, can you live with that?

 

Yup, DC gave a good summary.

 

Thanks folks.

@Ad Hoc : Namaste!! (the highest form of Indian greeting), for the sketch. Is it impromptu art?

@DCockey : Thanks for the unfussy reply. World seems much peaceful now (until somebody stirs it all up with an even better theory )