I'm running an emergency lighting calculation and I am puzzled by necessity to include the results of an invisible grid in brackets, I can understand that they are results which are based on a fine grid and will often provide more accurate results although this fine grid is not view-able or adjustable, I cannot find any part of EN12464 that insists on the grid being below 0.5m and the inclusion of this increases the calculation time. Is there any way to turn the calculation of the fine grid off or at least view the fine grid so I know the location of the shortfall in illlumiance?
so I think you've covered most points here and thank you for the clarification, however; my problem with this fine grid (and as raised in an earlier post) is the calculation time required.
I'm currently working on several warehouses, generally 350m long by 180m wide, and having three or four floors with differing ceiling and mounting heights.
The last calculation I ran seemed to spend 3-4 hours on the emergency calculation alone, which is making delivering designs to deadline difficult.
Would it be possible to have a checkbox system for whether this fine grid is used, and perhaps have a 'disclaimer' that automatically appears on the results page if it is turned off?
Perhaps something like "the designer has switched off the fine measurement grid feature for this measuring plane, and takes professional responsibillity for the results herein.".
I would suggest this is done on a plane by plane basis, as some smaller measuring planes would benefit from the fine grid, but the whole floor emergency plane could be done without the fine grid, hopefully saving calculation time.
Thoughts and comments are welcomed.
Dear Stuart Challenger
Your entire measurement area is part of the calculation and the result.In many cases this is no problem, for example if you duplicate your evaluation area
and change it into an emergency area, usually you will already have a distance of 0.5m between this surface and the wall.
If you create your emergency area using the poygon tool, remember to keep a distance of 0.5m from the wall.
Relux Informatik AG
Once 'off', always 'off'!
Dear Robert Stone
I can understand your wish for a faster calculation, but we need to make a fine-grid calculation to check if the results comply with the standards.
For the escape route as an example, we have to prove that the measuing surface has not less than 1 lux along the center line. Therefore ReluxDesktop has to place the measuing points very close to each other.
Without the fine grid, ReluxDesktop can no longer calculate the relevant results.
If the calculation takes too long, please check if your project contains too much information and if unnecessary objects can be removed.
We can also offer you to analyze your project and to give you some suggestions on how you can reduce the calculation time.
Relux Informatik AG
Thank you for the reply Basile.
Unfortunately I can't share my work, and there are times when the objects within the spaces are a necessary part of the contract design.
I guess I just have to be better at alotting time to design revisions.
Dear Luke Harrington
Maybe it'll help you, if i tell you, that the grid is adjustable.
Click on your Emergency Area --> Calculation --> Calculation Parameters --> and Remove the checkmark.
I hope thats solves your Problem.
Dear Bernard Glossop,
You misunderstood me, if you have a value below 1lx in the result overview, then this is usually because there is an area at the edge of your room which is not sufficiently illuminated.
The fine grid, which is displayed as a pseudocolor, shows this dark area pink colored.
Within the table you will find other numbers, beacause this calculation grid is not that fine. But the lowest numerical value is still written, as you can see in the picture below.
Relux Informatik AG
It does not solve my problem unfortunately, I still feel it is a bad inclusion to the program and it would be far better off without displaying/calculating that information, although I feel (as I did 7 months ago) that we are at an impasse... Relux feel that it is essential to include this information and I very much feel as though it is not, as a good lighting designer will always use sensible spacings anyway.
For example, the screenshot you have shown above details a calculation grid that displays spacings below 0.5m apart, with a minimum illuminance level of 0.6 lux, and there is a seperate figure (of which you cannot view as individual points - only a psuedo colour image) of 0.5 lux, now if the calcuation grid already contains calculation points which are below 0.5m, why would you need a second figure detailing calculation points which are also below 0.5m apart?
"we need to make a fine-grid calculation to check if the results comply with the standards." - Why? What part of what standard states that the measurement points need to be a certain distance apart?
It's mainly for large open area calculations using objects that I find this to be an issue, not very small escape routes as you have demonstrated.
I understand that many projects benefit from this feature, although there are also a lot of projects that are hindered by it, hence the multiple requests to have it as an option rather than a necessity.
Thanks for getting back to me (better late than never). Unfortunately you seem to have misunderstood my enquiry. Please see the below image:
When you produce an emergency calculation in Relux, there are 2 different calculations which are calculated within the same emergency measuring surface, if you look at the above results, you can see that there is a minimum level of 1.4 lux although the fine measuring grid provides a level of 0 lux. The method of adjusting the calculation points you have provided only refers to adjusting one of the two grids I have mentioned, it's the figure in brackets that I was referring to as I mentioned in my first post. The fine measuring grid (the figures in brackets) tells me that I have a minimum value of 0 lux although the grid that I have placed (and I'm able to adjust) gives me a figure of 1.4 lux, I'd like to remove the figure in brackets which is invisable, non-adjustable, for which you provide very little information of and is unnecessary to have on every emergency design.
EN12464 does not require calculation points below 0.5m to the edge of the area being calculated. So why calculate them? This implies that the program (app?) is calculating within this zone. The 'fine measuring grid' (0.1/0.2/0.3/0.4 metres?) are being taken into account and this is not a requirement of the standard. The 'fine measuring grid' is made up by Relux!
Dear Bernard Glossop
When we talk about emergency lighting, we have to check what is written in EN1838 (2014). Unfortunately, these papers do not provide us a standardized measuring grid which we can use for our emergency calculation.
It is only pointed out that this area must be illuminated with at least 1lx, apart from the border zone. Now it is impossible to know where the measurement will actually take place. Because of this lack of information, we use a fine grid for our calculation so you can be sure that you comply with the standard.
We can understand your issue, but if someone verifies your lighting calculation, you probably won't have any problems.
Relux Informatik AG
For those English speakers amongst us:
BS EN 1838:2013
Lighting applications — Emergency lighting
"4.2 Escape route lighting
4.2.1 For escape routes up to 2 m in width, the horizontal illuminances on the floor along the centre line of
an escape route shall be not less than 1 lx. The central band consisting of not less than half of the width of the
route shall be illuminated to a minimum of 50 % of that value. Wider escape routes may be treated as a
number of 2 m wide strips or be provided with open area (anti-panic) lighting."
I think that the point here is that as long as this rule is met then anything that falls outside of the 'not less than half of the width of the
route' area does not matter (0.5>0 lux). May be the escape route measuring area requires a 'task area' and a 'perimeter area' based upon the above.
In an open area (office) the standard states:
"4.3 Open area lighting
4.3.1 The horizontal illuminance shall be not less than 0,5 lux at the floor level of the empty core area which excludes a border of 0,5 m wide of the perimeter of the area."
A similar state of affairs has already been built into this regulation by the fact that a 0.5m border has already been defined, and the level of illumination does not matter beyond this to the room border.
So, from the above,
A corridor 0.9 metre wide would have a 0.225m exclusion zone to the corridor border,
A corridor 1.2 metre wide would have a 0.3m exclusion zone to the corridor border,
A corridor 2 metre wide would have a 0.5m exclusion zone to the corridor border, the maximum permitted under the Standard,
Your ongoing thoughts would be appreciated!
"In fact, if the firepolice measures with the luxmeter whether there is enough light on the floor during an emergency, they will probably go to the darkest place in the room and check whether there is enough light or not."
Do they also wait until the maintenance factor is down to the designed level and temporarily paint to walls to a 0% reflectance value and place the measuring point of the light meter at exactly 0.00m?
A competent designer will always use sensible measuring grid spacings, and I do not feel we need the lighting design program to dictate how far apart they 'need' to be.
Dear Luke Harrington