Dear All, I have a scaffolding platform which are being used for access only..the width is 4 boards, and 3 landing platforms with dimension of 1X 2 meters and 4 stairs each one with 3 meters lengths During rush hour, our people are afraid that the scaffolding may not withstand the load and may collapse Our contractor says, this is general Purposes scaffolding. Is written in scaf tag, 2KN /M2 Any help or advise appreciated to say whether scaffolding is strong enough or need some modification ..my calculations is below 220KG according the scaf tag First stair- 3 square meter=3x 220=660 approximate numbers= 10 x 65KG= 650 KG Note (usually is less than 10 people) during movement of people we consider it maximum and some for safety factor) First platform= 2 square meter-2X220=440 KG Approximate number =6x 65=390 Second stair= 3x 220=660 Capacity Approximate numbers= 10 x 65KG= 650 KG

I don't quite understand where your figures come from. 2kN is about 204kg. I don't know what your 220kg is. What the appropriate loading is for a temporary staircase very much depends on the application. For example, the Institution of Structural Engineers guidance 'Temporary Demountable Structures' references the Eurocodes for stair loadings for grandstands (ie, says temporary stairs must be designed to teh same standard as permanent ones), which is 4 kN/m2 (working loads - which means they should be designed for more than that before collapse, typically 1.5 x as much). However, that's foreseeing a case where the stairs are actually packed solid with a jostling crowd at the end of an event. Permanent institutional buildings which don't see crowds would normally have stairs and landings designed for 3 kN/m2, self-contained dwellings 1.5 kN/m2. If you have a staircase that does see a crowd, then that needs specifying to the designer (as ADALE says). As an aside, some structural design uses 76kg as the weight of an average person (but actually you very rarely work on a 'per person' basis - normally only when checking vibration).

I don't know enough to say whether your contractor is incompetent. It might be that whoever specified the stair is incompetent (that is, for example, if you asked him for a light duty scaffold, then if you got a light duty scaffold you can't say he was incompetent for not having provided a very heavy duty scaffold). I think you should be asking questions if you are putting a dense standing crowd on the stairs and they are only designed for 2 kN/m2. That's as much as feel able to say on the information available.

If you want to be picky, no, it's kgf (or possibly kgF) I was making the assumption that the scaffold is on the planet Earth at an altitude within a few kilometres of sea level. With that assumption, unless you're doing a dimensional analysis (or check) kg and kgf are interchangeable.

Thanks for comments, however i am still looking for pragmatic advice. SHV

It's important to remember what your question was asking and what is needed. Firstly, I can't tell from what the comments read so far as to whether you have seen a design to confirm any loadings at all - So to clear that up, anything other than bog standard scaffolding for ACCESS needs a design, specific to your needs and site - I would recommend if you cannot inspect scaffolds you seek competent advice, including my own. But furthermore, I'm a little worried too much reliance is on this scafftag system, as it doe not fulfil the whole requirements of the WAH 2005 regulations, something which commonly catches people out. From what I can read, unless I'm missing something, someone is trying to save money on a design somewhere, and on competent inspection somewhere else. I'm sorry I didn't get back sooner - D

Thanks for those who commented on my post ..Yes ADALE it is true, someone trying to save money in something,e.g competent scaffolder who could design according to the requirements SHV