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Gibbo
17-11-2013, 08:13 PM
Would appreciate any comments or help regarding the above regulation first saw it mentioned on the IOR website and subsequently on a GEA guide to refrigeration plantrooms.
It mentions about refrigerant practical limits relating to refrigerant charge versus plantroom size in regard to water cooled chillers it mentions refrigerants such as R123, Ammonia R134A, R410A etc.R123 and ammonia I was aware of the needs for R123 and Ammonia but I had never heard it mention for the other refrigerants in plantrooms.
Anybody familar with EN378-2008 or have a copy with the section on plantrooms, is it a legal requirement or not.

I am aware that there has always been practical limits for occupied hotel rooms etc in the case of VRF etc to prevent asphxyation.

Thanks Guys

Gibbo

install monkey
17-11-2013, 08:35 PM
The installer and system specialist shall secure safety against
leakage according to local regulations or standards. The following
standards may be applicable if local regulations are not available.
The VRV System, like other air conditioning systems, uses R410A as
refrigerant. R410A itself is an entirely safe non-toxic, non-combustible
refrigerant. Nevertheless care must be taken to ensure that air
conditioning facilities are installed in a room which is sufficiently large.
This assures that the maximum concentration level of refrigerant gas
is not exceeded, in the unlikely event of major leak in the system and
this in accordance to the local applicable regulations and standards.
Maximum concentration level
The maximum charge of refrigerant and the calculation of the maximum
concentration of refrigerant is directly related to the humanly
occupied space in to which it could leak.
The unit of measurement of the concentration is kg/m3 ( the weight in
kg of the refrigerant gas in 1m3 volume of the occupied space).
Compliance to the local applicable regulations and standards for the
maximum allowable concentration level is required.
In Australia the maximum allowed concentration level of refrigerant to
a humanly space is limited to 0.35kg/m3 for R407C and 0.44kg/m3 for
R410A.
taken out a vrv install manual

Gibbo
17-11-2013, 09:33 PM
Thanks IM

The info I have mentions chiller machinery plantrooms in particular as well as what you have just mentioned for normal occupied space.
For example if a chiller of 200kw with a charge of 60kg of R134A was installed in a plantroom it would require a minimum room volume of 240 cubic metres to avoid the practical limit and therefore the need for leak detection and any other safety measures such as ventilation linked to leak detection.
Anything less would require leak detection. This was taken from a GEA sheet refering to EN378-2008.
My question is if this is mandatory how come most plantrooms do not have leak detection etc as standard.
In your vast store of manuals do you have a copy of EN378-2008

Brian
26-11-2013, 09:22 PM
Hi if you could also help I am looking for a copy of BS EN 378:2008 1-4 also?
Cheers,
Brian

install monkey
26-11-2013, 09:32 PM
http://www.unep.fr/ozonaction/information/mmcfiles/7443-e-Ref_manual_servicing_technicians.pdf
click on the link above

Gibbo
30-11-2013, 09:02 PM
Many Thanks for Info IM

Gibbo

Rob White
01-12-2013, 03:01 AM
.

EN 378 Part 1 covers practical safe limits.

Max charge = Practical safe limit X Room volume.

If the refrigerant was R404A, it’s practical limit = 0.52 kg/m³
Room volume 4mtr X 6mtr X 3mtr = 72 m³

0.52 X 72 = 37 kg Of R404A

EN378 Part 3 covers ventilation rates.

Ventilation shall be 4 air changes an hour,
in an emergency Airflow shall be at least the quantity obtained by the following equation

V = 14 X 10¯³•m²/³

Where

V is the air flow rate in m³/s
m is mass refrigerant charge (in any part of the plant room)
14 X 10¯³ is a conversion factor

An emergency ventilation system with 15 air changes an hour is sufficient.


These are all based on C category rooms (limited access plant rooms)
using A1 type (non flammable) refrigerants.

Rob

.

install monkey
01-12-2013, 08:15 AM
nice info rob- but posting at 3am- thats dedication- then editing it too ;)

Gibbo
01-12-2013, 08:39 AM
Rob

Does that mean then that a leak detection system with external alarm to plantroom is a legal requirement or not when the refrigerant practical limit is exceeded. What other measures are required ?

Gibbo

Rob White
01-12-2013, 11:27 AM
Rob

Does that mean then that a leak detection system with external alarm to plantroom is a legal requirement or not when the refrigerant practical limit is exceeded. What other measures are required ?

Gibbo

Rooms are classed as occupied and unoccupied.

I would have to go back to the books,
it has something to do with 25kg of refrigerant.

Above that amount auto leak detection is a requirement.

If you go to the BSI web site you can get the EN378
and you can sit up until 0300hr looking through them :D

Regards

Rob

.

Rob White
01-12-2013, 11:36 AM
nice info rob- but posting at 3am- thats dedication- then editing it too ;)

EN378 normally puts me to sleep, but I'd looked this up
a short while ago because of some hydrocarbon refrigerant
training I was doing and I was not doing anything Sunday,
so I was catching up on Foyle's war and surfing the net.

Lazy day today and lunch out with a few friends :)

Rob

.

Grizzly
01-12-2013, 06:52 PM
Way off Rob.
More like 300kg before fixed detection systems are required.
Every engineer should have access to en378 as it is the fridgies bible.
If you refer to F gas regs they replicate some of en378.
Is it not something like 30kgs and a 6monthly leak check, 3kgs and an annual required?
Plant rooms are a specialised machinery space and as a consequence, have very specific rules.

How many realise that it is a legal requirement for a plant room to have a log book.

Which should be updated by all who visit the plant room and refer to what has been done?


I cannot quote any of en378 directly as this is a sackable offence and anyone is liable for prosecution!
No joke!
Grizzly

Rob White
01-12-2013, 07:51 PM
.

The inspection rates (yearly for above 3kg, quarterly for above 300kg's and such)
are slightly different to air refresh rates and leak detection for health & safety.

300kg's is the weight for automatic leak detection for large systems, but the
limit for health and safety is as low as 25kg's if the plant (machinery) room
has limited access (category c) and is based on the Practical safe limit, which is
the amount of refrigerant you can have mixed in air before it becomes a suffocation
risk (asphyxiation risk).

That is for A1 refrigerants which are "normal ones", the flammables (HC's) and the
toxic ones (NH3) have different classifications and therefore different guidelines apply.

Rob

.

Grizzly
01-12-2013, 08:23 PM
Hi Rob.
Don't question the trainer eh!
There is a lot in there is there not?
I removed approx 178kgs of R123 from a basement.
Prior to the builders knocking a big hole in the wall, which allowed me a safe airflow whilst removing said refrigerant.
There was limited access and no leak detection. Plus that was from the remaining centrif.
1 of 2 originally.
So I guess there are still some sites that don't comply?
Grizzly

Rob White
01-12-2013, 08:57 PM
Hi Rob.
Don't question the trainer eh!

If only :D I'm as bad as most guys when it comes to
reading the instruction manual...................................:o




There is a lot in there is there not?
I removed approx 178kgs of R123 from a basement.
Prior to the builders knocking a big hole in the wall, which allowed me a safe airflow whilst removing said refrigerant.
There was limited access and no leak detection. Plus that was from the remaining centrif.
1 of 2 originally.
So I guess there are still some sites that don't comply?
Grizzly


I think as with a lot of things in life the guide lines are there for
best practice and guidance and like a most things in life, nobody
gets to find out if nothing goes wrong.

I always say you can do anything you want in this world as long as
you have one of two things in your favor.

You can do owt you want in life, as long as you don't get caught
and if you do get caught, have a good solicitor. :D

Rob

.

Gibbo
01-12-2013, 09:48 PM
Many thanks Rob.


Gibbo

Brian_UK
01-12-2013, 10:54 PM
Hi Rob.
Don't question the trainer eh!
There is a lot in there is there not?
I removed approx 178kgs of R123 from a basement.
Prior to the builders knocking a big hole in the wall, which allowed me a safe airflow whilst removing said refrigerant.
There was limited access and no leak detection. Plus that was from the remaining centrif.
1 of 2 originally.
So I guess there are still some sites that don't comply?
Grizzly
Sorry off topic but, been down the Riviera then Grizzly?

Grizzly
01-12-2013, 11:12 PM
I was going to give you a mention Brian, I thought the hole may have been from you venting your kit!!!;)

Surreal down there at present is it not?
Grizzly

Brian_UK
02-12-2013, 11:17 PM
One of our guys got a 2am callout when their one and only boiler stopped firing, oh he did enjoy that.