This video from the 2022 NCC Seminars discusses Section D Access and Egress, and Section F Services and Equipment from NCC 2022 Volume One.

Transcript

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[Music]  

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Hello my name is Graham, from the Australian Building Codes Board  this video is an update on Sections D and E 

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access and egress and services and  equipment of NCC 2022 Volume One.

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First change to talk about today is in D2D3  number of exits known in 2019 as D1.2, now I've  

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got D1.2 on the screen here from 2019 because I  want to show you something that we've changed for  

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2022. Notice that number of exits required for a Class 2 to 8 building over 25 meters

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effective height that each story would  need to have at least two exits and that makes  

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sense because tall buildings present evacuation  difficulties. Now D1.2b has to be read alongside  

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subclause (g) and subclause (g) says that every  occupant of a story, including the ground story,  

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in that 25 meter building needs to have access  to at least two exits if two exits are required.

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Now consider your typical hole in the wall  cafe at the ground level of a building,

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like the one pictured here, now if this  building exceeded 25 meters effective height  

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then the cafe will not comply with D1.2 unless  there's two exits, even if all the travel distances  

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required by D1.4 and other parts of the NCC are  met because D1.2(g) is saying you have to, that  

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every occupant of that particular story including  those in the cafe need to be able to get to at

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least two exits without passing through another  sole-occupancy unit. So for NCC 2022 we've updated  

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D2D3 to remove that requirement for the second  exit for a part of a building like that cafe

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which would otherwise meet the travel distance  requirements of the BCA. Now on the screen we have  

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D2D3(2)(b) which applies for Class 2 to 8s there's also  a similar exemption for Class 9 buildings in 4B.

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The next change to show you is dimensions of  exits and here on the screen we have BCA 2019  

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now you're probably aware that exits and paths  of travels to exits need to be at least one meter

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wide that's the D1.6(b)(i). Now you're probably  also aware that in certain circumstances the BCA  

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allows a ladder to access a space so for instance  consider a plant room less than 100 square meters  

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it's possible to use a ladder that complies with  AS 1657 instead of a traditional step and riser  

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arrangement in accordance with BCA 2019 D2. Now  those ladders are technically a path of travel to  

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an exit and ladders are typically less than one  meter wide therefore for NCC 2022 we've included  

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this exemption in D2D8 which was D1.6 to include  ladders. Now note that these ladders, this exemption  

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for ladders are only for ladders that are included  for the reasons of D2D21, D3D23 and I3D5 that's  

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D2D21 for plant rooms the 100 square meter  plant room concession I mentioned just now  

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D3D23 which is that provision that talks about  allowing AS 1657 platforms and ladders for  

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service and storage areas and also of course  I3D5 is the provision for farm buildings.

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Now the reason we've actually specified that  is the ladder must be provided in accordance  

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with these provisions or for the purposes  of these provisions is that we don't want  

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people coming to site and finding that the  exit path is less than one meter and think  

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okay here's the solution I'll put in a ladder no  it doesn't work that way because the ladder must  

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be there for the reasons of those provisions  not because there's a pinch point on site.

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This next change is something new but at  the same time it might look familiar to you  

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and that's because for NCC 2022 except for a  standalone primary school that's no taller than  

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four stories every part of that primary school  must be wholly within a story that provides  

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direct egress to road or open space this is a  new Deemed-to-Satisfy requirement for NCC 2022.

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If you want to do something different to that  so for instance a five-story primary school or  

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a primary school in a mixed-use building where  the primary school does not have direct egress 

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then you need to do a performance solution. As  pointed out by the explanatory information on  

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this slide this is because of the difficulties  associated with the evacuation of primary schools.

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Now if this does sound familiar to you that's  because you're thinking of D1.18 in NCC 2019, which  

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does similar things for early childhood centers.  Now basically what we've done with this provision  

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is taken early childhood center and replace that  with primary school, now we've done this because  

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for early childhood centers we've introduced  additional Deemed-to-Satisfy provisions which  

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I'll show you in a moment,so that it's no longer  necessary to do a performance solution for all  

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primary for all early childhood centers that  exceed the parameters that are found in D1.18.  

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So what was the case for early childhood centers  is now the case for certain primary schools  

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and those are these so consider building a  building A is going to be a performance solution  

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it's all the same primary school it's a  single-use building, however the building  

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exceeds four stories and therefore a performance  solution is necessary it's not possible to  

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use the Deemed-to-Satisfy provisions of the  building code as is the case under NCC 2019.  

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Now building B is within that four-story limit  it's not a mixed use building and it's all the  

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same primary school so under D2D23 it's okay  to use the existing Deemed-to-Satisfy provisions.

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Consider building C, building C is also under  four stories but it's a mixed-use building now  

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a mixed-use building does increase complexity for  evacuation however the primary school is at the  

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ground level and therefore has direct egress,  so under D2D23 you can use existing Deemed-to-Satisfy

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provisions as is the case under 2019. But  consider building D the primary school is in a  

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mixed-use building yet does not contain direct  egress there's another use below it therefore  

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building D a performance solution would be  required under these new provisions in NCC 2022.

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This new provision D2D23 for primary schools  

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has some applications to go with  it found in the application box

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now this first application box is clarifying  that when we're talking about a primary school of  

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course we're talking about kindergarten to year  six which is what the Department of Education  

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calls a primary school but the application box  is saying that when we're talking about a primary  

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school we're talking about parts of a school  where it's reasonably expected to find students.  

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So the staff rooms you could find a  primary school student in the staff  

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room you could find them in the classrooms  of course, the offices, the canteen these  

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are all parts of a primary school where  the vulnerable occupants can be found.

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Now primary schools are very often found on the  same campus or even in the same building as a  

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high school or an early learning center or other  parts of a school which is still the same school  

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and that's why we have this second application.

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What we're saying is that we have a primary school  and a high school and it's all the same school and  

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it's all in the same building then there's no need  to treat the building as a multi-use building for  

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egress because the whole building has the same  occupant the evacuation problems that would be  

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found in a traditional mixed-use building aren't  present. So the second application box says that  

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it's still a Deemed-to-Satisfy solution if you're  less than four stories and the primary school is  

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part of a bigger school and note also this  extends to the offices, it also extends to  

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a different classification a Class 7a car park  where it's a car park for that particular school.  

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Now that's the new primary school provision  which is requiring performance solutions for  

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large or difficult to egress primary schools. Now I  mentioned earlier that what we'd had done is taken  

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early childhood centers out of D1.18 and replaced them with primary schools we're now going to cover  

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the changes or the additional Deemed-to-Satisfy provisions for early childhood centers. Now these  

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are all the provisions that have been amended to  accommodate these new provisions. We're not going  

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to cover every amendment in detail but I do want  to zoom in on this one A6G1, part of the governing  

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requirements, now note that this applies to all  early childhood centers in mixed-use buildings. 

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This is the 10% concession you know the 10 rule  where if you have multiple classifications in the  

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same story and one classification is less than  10 percent of the total area of the story then  

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you can apply the main classification the  greater classification to the entire story.

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Now for a long time that concession  hasn't applied to laboratories or to  

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residential solo units this year as shown on  this slide we've added early childhood centers.

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Now the reason we've done this is because  otherwise if you had a large building like  

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this Class 6 shopping center and the Class 9b  early childhood center was this little part here  

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then that would be less than 10 percent  and become a Class 6 shop instead of a  

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class 9b early childhood center and then would  miss out on all these additional provisions.  

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Now you may be thinking that this hypothetical  early childhood center that I've shown here is on  

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the ground floor has direct egress and therefore  would not require the additional provisions now  

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for most of the provisions that is the case they  don't apply, however sometimes they do. I'll show  

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you as we go through these provisions which ones  do and which ones don't apply to early childhood  

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centers with direct egress, but first I'll show you  how that's achieved and it's achieved by way of  

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these limitation boxes. So these limitation boxes  are found when something won't apply to an early  

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childhood center that has direct egress or to an  early childhood center that's a standalone center

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of only two stories or up to two stories. So this  is a particular example is found in

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Specification 17 Clause 14, which is a new provision that  requires quick response sprinklers for an  

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early childhood center that's at height. Now note  how the limitation box removes that require for  

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quick response sprinklers to the early childhood  centers that are low risk that have direct egress  

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and only a standalone story standalone  center up to two stories rise in stories.

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Note carefully that some of these new provisions  do apply to early childhood centers like those  

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depicted on this diagram those that have direct  egress or are only up to two stories in standalone.  

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I will point it out where they do though  most of early childhood centers they're  

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at height that don't have direct  egress, like this one for fire isolation.

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If the early childhood center is in a mixed-use  building it needs to be fire isolated from the  

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remainder of the building if you don't have direct  egress as shown on the right the diagram on the  

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left the ECC the early childhood center has direct  egress and therefore C3D6 does not apply there's 

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no necessity to fire isolate the early childhood  center from the remainder of the building.

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So next is compartmentation within the story  itself so each story the center needs to be  

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separated into at least two fire compartments  of course this applies only when we're at EEC's  

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that are at height, this won't apply to the  single story direct egress or the double  

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story direct egress early childhood centers. Exits, so if you have an exit ramp it needs to  

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be fire isolated again this only applies to the  early childhood centers that are found at height . 

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Also in Part D2 is horizontal exits where you have  to divide your story into fire compartments each  

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compartment has to have at least two horizontal  exits and of course those exits need to be at  

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least nine meters from one another and also nine  meters from any other exit. You also have to be  

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able to fit the entire population of the story  in either fire compartment you can see that  

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these provisions are about creating opportunity  for staged evacuation getting the vulnerable  

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occupants away from the fire affected compartment  which of course buys time for assisted evacuation.

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Next in Part D3 we require appropriate handrails  and balustrades you may be aware that in a primary  

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school we require additional kid-sized handrails  for stairs and ramps to in addition to those that  

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are required for adult size, we've got kids size  handrails. Well for NCC 2022 we now require toddler  

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sized handrails for early childhood centers. Now  note carefully that there's no limitation box  

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on this new provision this applies across all  early childhood centers, also I need to point  

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out for Part D3 that even though in the example  on the screen here we have fire isolated exits  

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you'd be aware that fire isolated exits have a  concession in the barrier for 300 sized openings  

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300 millimeters instead of 125 millimeter size  openings well for an early childhood center that  

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concession is removed you must bring it down  to 125 millimeter opening maximum because of  

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course we have little people using these exits  and therefore we need to make them suitable. 

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Finally sprinkler protection now sprinklers  aren't required in that standalone early  

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childhood center up to two stories in height or  where we have direct egress, but in a mixed-use  

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building like the one shown on the right where  the early childhood center does not have direct  

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egress then the whole building not just the early  childhood center but the whole building needs  

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sprinkler protection and as I showed earlier the  early childhood center needs quick response heads.

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I just want to point one thing out about those  quick response heads and I'll do that using the  

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examples shown on this slide. On the left here we  have an early childhood center in a building that  

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exceeds 25 meters effective height so of course  on account of exceeding 25 meters effective height  

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the building on the left requires sprinkler  protection. Now the early childhood center

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is receiving sprinklers in that building on the  left not because it's an early childhood center  

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because as you can see the early childhood center  has direct egress these additional requirements  

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don't apply. No, that early childhood center is  receiving sprinklers because it's in a building  

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that exceeds 25 meters effective height, in that  case standard heads are fine they're satisfactory.

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Now consider the building on the right that  building needs to be sprinkler protected  

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because it exceeds 25 meters effective height  that's true but note the early childhood center  

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is found at height there is no direct  egress and therefore that provision I showed  

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earlier applies and the early childhood center must have quick response heads.

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Finally smoke detection now note that this one  applies to all early childhood centers that is  

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for NCC 2022 smoke detection and alarm systems are  required now in every building that contains an  

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early childhood center. Including those that enjoy  direct egress, no limitation box found on this one. 

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so those are the changes  for early childhood centers.

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This next change is D3D16 currently known in NCC  2019 as D2.15, now for 2022 we've added the words  

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in resident use areas for Class 9c residential  care buildings that's there in subclause (b).

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I've shown you this definition on this screen we're  talking about the residential areas of a building.

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Now you'll notice that this matches subclause (a), which describes hospitals and how the patient care  

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areas for a Class 9a healthcare buildings  are the only parts caught by subclause (a).  

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Now this is fixing a small problem that's  currently in the code because currently you  

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can't have a step anywhere near the threshold  of any doorway in the whole Class 9c building,  

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even the back door used only by staff where a step  is going to be useful to stop the rain coming in.

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Now in the current code subclause (b) overrides (d) which is the concession that allows that back  

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door to have a step. Now i'm told this  is a common performance solution for 

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really what is an unintended oversight in  the code so that's now fixed for NCC 2022.

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This next change is to do with balustrade  specifically face mounted balustrades and note  

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this changes found in Volumes One and Two. When I  talk about a face mounted balustrade that might be  

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achieved by a spigot mount or it might be achieved  like a bracket mount like in this photograph.

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This is any configuration that's creating a gap  between the edge of the traffickable surface  

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that's been protected and the balustrade, now some  might say that under the current code that this  

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is this face mounted balustrate is okay so long as  that gap doesn't allow a 125 millimeter sphere to  

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pass through, however a 125 millimeter gap is a big  gap in that location and also I want to suggest to  

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you that if your barrier is set away from the  side especially 125 millimeters away then it's  

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hard to say that your barrier is provided along  the side of the traffickable surface which is  

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the current requirement shown here for BCA 2019  Volume Two, similar wording is found in Volume One.  

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However we do note that this is a popular  balustrade design and therefore we've included  

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for both Volume One and Two this edition that  is we're allowing face mounted barriers so  

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long as the gap measured horizontally doesn't  exceed 40 millimeters. Now please do note that  

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this 40 millimeter allowance doesn't somehow  stack with 125 millimeter provision that  

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exists today so you can't get a larger gap  from that 125 it's still the case that the  

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125 sphere can't pass through any part of the  barrier it's simply that we're permitting the  

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barrier to be located away from the edge so long  as that awayness doesn't exceed 40 millimeters.