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Support => Plumbing, Gas fitting and Drainlaying Apprentice Support => Topic started by: sharks on April 28, 2011, 11:11:27 PM

Title: certifying exam ?? Is this right
Post by: sharks on April 28, 2011, 11:11:27 PM: Please help me out here. As far as i know you cant do what theyve done in this question. Please , if im wrong , can you tell me where I can find it in as/nzs 3500.

Q 17 in nov certifying exam asks you to draw in the drains. http://www.pgdb.co.nz/~downloads/9195Q%20November%202010.pdf (http://www.pgdb.co.nz/~downloads/9195Q%20November%202010.pdf) (thats the link to the Q , just scroll down)

The answer that they give , http://www.pgdb.co.nz/~downloads/9195A%20Nov%202010.pdf (http://www.pgdb.co.nz/~downloads/9195A%20Nov%202010.pdf) (the answers they give , scroll down to 17)
With elavated drainage , min size is 65mm and they are running 40mm , so they cant be using that.
Under the single stack system with 1 section of floor graded (8.8.5 as/nzs 3500) everything must enter the main drain individually and if not must be vented.Theyve got a WC and basin combined , so surely cant be that.

Thanks guys
Title: Re: certifying exam ?? Is this right
Post by: Plumber on April 29, 2011, 06:53:16 PM: Just answering by memory here and on the fly : Anything "not underground" is considered a drain, where as anything inside the ground is considered a sewer, So the rule min 65 only applies to a sewer. When you do an underslab and have a foorwaste, you can charge that floorwaste with a 50mm pipe (also considered drain) after the floorwaste it has to be 65mm (considered sewer). Then you can calculate the drainpipe size by using your fixture units. Hope this helps! ;D
Title: Re: certifying exam ?? Is this right
Post by: Plumber on April 29, 2011, 06:54:58 PM: The only mistake I see is the 60mm LOL
Title: Re: certifying exam ?? Is this right
Post by: sharks on April 29, 2011, 08:01:18 PM: hey karma , thanks for your response. In the modal answer that they give they have a 40mm discharge pipe connecting into the main suspended drain so I dont think theyre using drainage princibles. Just not sure what rule they are applying to this system. I have contacted Jose at the board and he reckons he will forward it on the the appropriate person. See how we go!!!!
Cheers
Title: Re: certifying exam ?? Is this right
Post by: TS on June 04, 2011, 09:59:37 AM: I think the drawing is wrong also. They also state gradients of 1:60. This is too flat for 40mm and 50mm.
Title: Re: certifying exam ?? Is this right
Post by: TS on July 01, 2011, 05:39:59 PM: How have you gotten on with this?