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Josip
04-06-2016, 11:11 PM
Dear all, :)

need your help ... cannot find by myself,(maybe searching in the wrong way), but I am sure you know ...

Question is:
when (if?) is needed to have operator/s 24/7 in engine room with refrigeration plant working with ammonia?

If we need operators by the law: what is merit ...
Is it installed power, or amount of refrigerant within plant (ammonia) or just safety request? ...

Is there some law about within Europe/world ... some recommendation ... decision .. whatever ...

Please give me some links if available or send relevant document/s to me.



Thanks a lot for your time and effort.

Best regrds, Josip :)

Segei
04-06-2016, 11:32 PM
I think it is different even in one country as Canada. In province Ontario it is based on compressors HP. Below 200 HP unattended, 200 - 400 HP 8 hours per day coverage, > 400 HP coverage 24/7.

RANGER1
05-06-2016, 12:24 AM
Josip,
May not be totally relevant but good information & links

https://www.epa.gov/sites/production/files/2015-05/documents/accident_prevention_ammonia_refrigeration_5-20-15.pdf

RANGER1
05-06-2016, 12:29 AM
Josip,
May not be totally relevant but good information & links

https://www.epa.gov/sites/production/files/2015-05/documents/accident_prevention_ammonia_refrigeration_5-20-15.pdf

It would also no matter what region how well plant is set up with ammonia detection, shunt trips, age of plant, how automated, close proximity to populated areas.
Lots of plants in Australia do not have operators at all, but plant over 200 tonnes different laws take effect.
Process plants would have someone who is knowledgable as no producyion, no money.

Josip
05-06-2016, 06:52 PM
Hi,:)

thanks a lot ....

seems, like a little bit different all around the world ... this is for Canada and for USA ... hope to get some info about regulations within Europe ...


Best regards, Josip

Rob White
06-06-2016, 12:11 AM
Hi,:)

thanks a lot ....

seems, like a little bit different all around the world ... this is for Canada and for USA ... hope to get some info about regulations within Europe ...


Best regards, Josip


It is all specified in EN 378.

I have copies on my work pc so could look tomorrow
but I don't think there is a requirement for manned
personnel attendance. It is all about auto leak detection
and ventilation rates when it detects the refrigerant.

Rob

.

Josip
06-06-2016, 08:30 AM
Hi, Rob :)

thanks a lot ...


Just thinking out loud ...

all around in documents we have a tons of guidelines how to manage-install leak detectors and about ventilation ...

nothing about required personnel attendance .... why is that kind of recommendation-regulation missing ....

... in case of leak i.e. plant shutdown ... without any skilled personnel present, to solve the problem, all production is stopped ... what means lost on both fronts ... no safety and as Ranger_1 wrote ... "no production no money"

A little bit strange, at least for me:confused: ... yes, I know employed personnel must be paid for work ... but that should not be a reason to gamble with safety ....

maybe someone can explain that from some other point of view ...

Thanks


Best regards, Josip :)

RANGER1
06-06-2016, 09:58 PM
Josip,
We find companies reducing staff all the time to save money & call service companies to repair.
Automation has changed how people run plants if labour is expensive (like in Australia).
Ammonia plant operators almost non existent in Australia as they used to run boilers which are now mostly automatic as well.
There is usually someone who knows something on these sites that can take instructions or make safer until service company arrives.
A lot of plants especially with lots of people in production areas use secondary refrigerants like glycol.
Older plants have to work towards this as if something happens, people hurt, investigations, fines etc.

Unless it's a catastrophe most people let you know of a leak probably before ammonia detection systems.

If safety trips are checked regularly, relief valves checked/changed regularly, pipework checked repaired etc I guess it reduces risk of leaks, it's ongoing.

To me unusual to have major leak unless by human error, like forklift damaging pipework, oil draining, so procedures & safety barriers could or have been implemented.

We had one plant that did have a major ammonia leak on plate freezer, so automatic shut off valves installed linked to ammonia detection. At least it could be contained.

Some places use ammonia concentration monitors to show workers that they are in no danger, as usually they want to stop work for any reason.
In some cases people have a panic attack & go to hospital, because of a small ammonia smell.

If a plant is assessed & all are different, maybe some safety procedures or safety recommendations can be made.
If in remote areas the people are usually independent to a certain degree as a matter of necessity.

Josip
07-06-2016, 12:43 PM
Hi, RANGER_1 :)

thanks for your comment ... a lot of truth ...


for sure we have to accept changes which are coming with new era ...

... much more automatic control - shutt of valves .... ammonia sensors ... and other protection measures...

... secondary refrigerants within production area ... at least where is possible ...

or silent killers (with CFC, HCFC or HCF) installed units ...


.... the same is also within refinery and petrochemical plants ...
operators are monitoring equipment on regular base - walking around and checking equipment every 2-3 hours ... listening some strange noise, if ... checking for leaks ... process and all other parameters are controlled within control room ...

... of course this is industrial plant with 24/7 production and safety rules are quite high

... anyhow present work force-operators are reduced ...


Thanks to all for help.


Best regards, Josip :)

cduque
12-07-2016, 03:14 PM
Hi Josip,


As far as I know the reglementary situation (laws) is considerably different from country to country. In Europe there are countrys with ammonia refrigeration plants licencing very strict (ex. France) and others where the process is much more "easy" or even not existing. (this is opposed with F-Gas regulation, with strict rules all over Europe...)

Another thing are the standards, normaly not obligatory unless stipulated in the contract. EN 378 is an example and in Europe, when this standard is fully implemented, the legal acceptance is normaly easy.

Anyway I don't know any country where a human presence is obligatory in an NH3 machine room, as it was the case with boilers and vapour instalations some years ago.


Now there are many safety procedures, safety equipments and space organisation that may overcome the need for an human presence in any machine room. I believe that this is an organizational option in any plant, since an unattended instalation may need a bigger level of safety, control and alarm communication.

Best regards,
Carlos