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Grizzly
20-12-2007, 05:35 PM
I was talking to a Grey haired Security Gaurd recently.
Who turned out to be a Ex City of London Fireman.
Who's eyes lit up when I said I worked with Ammonia. He went on to tell me about how back in the 60's when introducing new recruits to Ammonia.
They would place a bucket of water on the ground.
Pour some liquid Ammonia on the ground about 2 feet away.
And watch first the evapourating Ammonia gas travel to the bucket. Followed slowly by a trickle of liquid ammonia.
So say along the floor and up and into the water.
Whats think then guys fact or fiction?
May I just say on behalf of the many others out there it certainly does find your moist bits.
Grizzlyhttp://www.refrigeration-engineer.com/forums/images/icons/icon5.gif

nh3wizard
20-12-2007, 09:04 PM
Sounds like fiction to me, as far as the liquid ammonia Traveling into the bucket

hendry
24-12-2007, 05:08 AM
have not done that.

but, my last ammonia leaking job along with local fire brigade was the most memorable one.

the leak was during holidays in early feb 2007.
as early as 0700hrs i have received call from GM of the company.
by the time my technican arrive on site, keep-off lines have been put up. few fire engines has arrived on site.

white smokes are coming from the leaking poins. it is a hi-lo stage liquid pumped system.

accessibility was poor then plus others are not familiar with the place.

however, the main valves and branch valves were isolated along with others equipment. [practically the whole area is shutdown]

you know what ...
when i went in with only full facial mask with K2 filter, i came out with my lower body feel burning hot.

good experience then ... but scary ... the smokes looks as if you are in heaven ...

Grizzly
24-12-2007, 04:56 PM
have not done that.

but, my last ammonia leaking job along with local fire brigade was the most memorable one.

the leak was during holidays in early feb 2007.
as early as 0700hrs i have received call from GM of the company.
by the time my technican arrive on site, police lines have been put up. few fire engines has arrived on site with few fire chief of nearby stations around.

white smokes are coming from the leaking poins. it is a hi-lo stage liquid pumped system.

accessibility was poor then plus fireman are not familiar with the place.

however, the main valves and branch valves were isolated along with others equipment. [practically the whole area is shutdown]

you know what ...
when i went in with only full facial mask with K2 filter, i came out with my lower body feel burning hot.

good experience then ... but scary ... the smokes looks as if you are in heaven ...

Hendry
Thanks for an interesting post allbeit a little scary!
In the U.K.
It's been a very long time since it was acceptable to deal with a leak using just a resperator.
Yes we have all, whilst working on plant walked away from a small leak donned a resperator and shut the relevant valve.
But a major leak should be a chemical suit and Breathing Apperatus.
Nowadays as a contractor should a situation occur. Company Practice is for us to advise only and let the fire Brigade deal with it.
Personnaly I would be willing to don a chemical suit and assist them. I've seen what they can do when left alone to it!
Yes we have all had some INTERESTING REACTIONS from the Fire Brigade, especially the retained/ Part time guys.
I will tell more in the New Year as I don't want to hog the forum. Suffice to say there have been some amusing situations.
Got to go the festivaties are nearly upon us.
Grizzly http://www.refrigeration-engineer.com/forums/images/icons/icon14.gif

Andy
25-12-2007, 04:52 PM
have not done that.

you know what ...
when i went in with only full facial mask with K2 filter, i came out with my lower body feel burning hot.

good experience then ... but scary ... the smokes looks as if you are in heaven ...

Hendry:)

you might need some cream on that:D

Kind Regards Andy:)

hendry
26-12-2007, 11:09 AM
Hendry:)

you might need some cream on that:D

Kind Regards Andy:)

yeah .. that's what the nurse says when i went for checkup.

Tycho
28-12-2007, 05:16 PM
Sounds like pure fiction :)

Ask him if the ammonia went into the bucket and closed the lid after itself too :D

---------------

Talk about burning, small cuts on your hands, sweating under the arms and in the crotch... very unpleasant :)


Was replacing a refrigeration pump a few years back, had drained it and taken off the flangebolts and foundation bolts, I was standing with one leg each side of the flange and tilted the pump over so the other guy could grab it... the remaining gas was aimed perfectly at my nether regions, can safely say it was a "burning sensation" :) after that I started attaching the vacuum pump a few minutes before taking the flanges apart :)

US Iceman
28-12-2007, 08:52 PM
you might need some cream on that:D


Trying to explain a diaper rash as an adult is a difficult situation.:rolleyes:

I used to keep some of this with me all the time. It's better to be comfortable, than painful.;)

hendry
03-01-2008, 06:12 AM
yeah ... talking about fiction ...
i've removed piping isntallation which on the outer surface it is severely rusted but what was inside ...


IT IS LIKEK NEW!!

"what inside counts, huh?!"

to my surprises, internal surface is very much as newly fabricated; not even a pitting is found compared to external of total-write-off.

believe it or not ...?

Josip
03-01-2008, 11:19 AM
Hi, Hendry :)


however, the main valves and branch valves were isolated along with others equipment. [practically the whole area is shutdown]

you know what ...
when i went in with only full facial mask with K2 filter, i came out with my lower body feel burning hot.


.....all valves isolated (assume no more liquid ammonia leak).....place full of smoke...and getting in only with facial mask:eek:....for me was not very clever action....in that area you can get in only with full protection suit and with breathing unit on your back...

....seems all of you were in panic....you should wait and not put others and yourself in danger more then need...damage has been done...leak of couple of liters more or less does not change nothing but can kill you...hope you learn something.....NHF, please ;)


good experience then ... but scary ... the smokes looks as if you are in heaven ...


experience, yes....good or bad...depending if you learn something or not...., but definitely it looks more like a hell...

....was in similar situation and for sure I know what I am talking about....unfortunately ammonia is deadly dangerous friend....like water sometimes...;), and we need to act accordingly...



yeah ... talking about fiction ...
i've removed piping isntallation which on the outer surface it is severely rusted but what was inside ...


IT IS LIKEK NEW!!

"what inside counts, huh?!"

to my surprises, internal surface is very much as newly fabricated; not even a pitting is found compared to external of total-write-off.

believe it or not ...?

it is true...... in ammonia plants pipes are almost intact....inside, but from outside due to improper insulation too much problems (especially with Armstrong armaflex insulation - for me only good for copper and SS pipes)...otherwise with injected PU foam

Best regards, Josip :)

hendry
04-01-2008, 06:00 PM
further to earlier story-telling ....

the designs are not developed by local ....:rolleyes:

added to it, the project team allows ammonia piping in enclosed space installation ... crawling distance end-to-end of aprox. 20 feet.

more to it, [be careful, someone is watching ...:)] i was like a tour guide showing someone around [in chemical suits] & narate the situation/s.

i was offered chemical suits but i declared that i wasn't trained but with prior fire rescue experience, we went in ...

by the way, the white smoke was about 4 ~ 5 feet from us during the "tour" .... we are slightly on higher ground approx. 2 ~ 3 feet.

my meaning of experience is "the process".

to me, heaven & hell do not have differences. i can be in heaven but ill-treated. contrary, i may be in hell now but highly praise!

eventually, the most important lesson, the company does not deserve all parties' helps on that day ... :confused:

Josip
04-01-2008, 06:22 PM
Hi, hendry :)

I see, :D


more to it, [be careful, someone is watching ...:)] i was like a tour guide showing someone around [in chemical suits] & narate the situation/s.

....hope you got a chance to improve something there...maybe to replace the whole plant with ***** type;)

Best regards, Josip :)

hendry
04-01-2008, 06:27 PM
haven't been there lately ...
hearsay, they found cheaper refrigeration "specialist" ...

we move on ... with dignity!

paulbuckmaster@
08-01-2008, 10:07 PM
when i was doing my apprenticeship at the cold store it was all ammonia cant remember the tonnage but it was massive, and when i say cold store i mean warehouse freezer !!!
but i remember quite Afton on the old sterne compressor carbon gland seal would crack and ammonia pour out causing the whole industrial estate staff to cry finding the fire brigade spraying water into the air to absorb the ammonia ,
after a while you do get used to it i would often walk into the plant room with someone to find them bolting out the door "crying"
when taking oil out the system the ammonia would "roll" out the bucket and cause an eerie mist across the floor .oh memories

josef
09-01-2008, 01:26 AM
Tycho lid, Andy cream, US Iceman plenum and tailwind. :D

TXiceman
10-01-2008, 03:17 PM
Hi, hendry :)

I see, :D



....hope you got a chance to improve something there...maybe to replace the whole plant with ***** type;)

Best regards, Josip :)

Now why in the world would you want to replace an NH3 plant with *****.....Better to learn how to handle the ammonia properly.

Ken

Josip
11-01-2008, 08:24 PM
Hi, TX Iceman :)


Now why in the world would you want to replace an NH3 plant with *****.....Better to learn how to handle the ammonia properly.

Ken

I'm sorry Ken, you miss my point, please read my sentence again...I wanted to say something else....I was not serious.........usually ***** guys take opportunity (if there is some small ammonia leak) and suggest to owner to replace ammonia plant with "the perfect one, with green *****-no smell, no harmful, energy saving.....etc, a lot of bull s**t", but you know stories like that;)


Better to learn how to handle the ammonia properly.
....agree 100%....

I'm definitely the last guy who will suggest replacing ammonia with any ***** for industrial use, something like that for me is a criminal act.....please check my posts regarding ammonia...

Best regards, Josip

TXiceman
14-01-2008, 05:14 AM
I have had Petro Chemical customers flatly refuse to even consider Ammonia as it was too dangerous. Never mind the fact that they are process cyanide, phosgene, propane, propylene, ethane and several nasty oxide compounds.

Usually the plant safety and environmental experts get in the picture and they want every thing safe and green and have been sold a bill of goods by the local DuPont salesman pushing of all things R-134a.

If ammonia is so dangerous, sure a lot of dangerous food plants. I did get one petro chemical customer to visit a large pizza topping and meat processing plant. The plant had close to 5000 HP split between 2 engine rooms. They were clean, and no ammonia smell.

They came away impressed and finally did buy an ammonia system from me over the specificied "*****" design.

Ken

US Iceman
14-01-2008, 06:38 AM
The only time I had a problem selling an ammonia system to a chemical plant was in a chlorine facility. There was no way they would touch it, so we ended up using R-22 (about 80,000 pounds:eek:).

PaulZ
15-01-2008, 08:06 AM
Hi US Iceman
I think you will find the reason the chlorine facility wouldn't touch it is NH3 and Chlorine can form explosive compounds.
The same goes for silver, mercury, iodine and hypochlorites.
Paul

US Iceman
15-01-2008, 05:35 PM
Hi Paul,

Yeah, I was aware of those problems. They told me they had those on site AFTER I suggested ammonia.

Oh well, it's better to find out earlier, rather than later.

grump
21-01-2008, 03:27 PM
Hi Fellow HVAC/E/R My background in electrics was not without its dangers.I came into this industry in 1976 working with ammonia (Arkla Servel )also R22.Now i had to be aware that there were many hidden dangers ammonia vapour, phosgene, high pressure,moving parts,electric shock,liquid refrigerant,parking wardens.
Now i have a question, would you rather be exposed to ammonia vapour or phosgene gas?
In his contribution paulbuckmaster mentionend Sterne
Compressors where were they built? clue gods country, where many a good engineer was conceived
Grump:D:D:D

Grizzly
21-01-2008, 06:39 PM
Phosgene gas is also known as Mustard Gas. That which was used in the First World War.
I don't know wether you can recover from a dose of it?
But I do know you can recover from A good dose of Ammonia Vapour. (B.T.A.G.TS)
OK Grump I will ask why Traffic Wardens?
Grizzly

US Iceman
21-01-2008, 10:11 PM
...would you rather be exposed to ammonia vapour or phosgene gas?


Ammonia, no doubt about it. The human body can metabolize small levels of ammonia with no undue reactions.

Tycho
21-01-2008, 10:34 PM
Phosgene gas is also known as Mustard Gas. That which was used in the First World War.

Grizzly



WROOOOOOOONG!!!!!

Phosgene gas IS NOT the same as mustard gas...

Phosgene is a mix of chlorine and carbon monoxide. It is colorless and odorless and it attacks the lungs, causing edemas... simply put, it drowns you in your own body fluids....

----------------

Mustard gas is synthesized by treating sulfur dichloride with ethylene.

copied from wikipedia: Mustard gas is a strong vesicant (blister-causing agent). Due to its alkylating properties, it is also strongly mutagenic (causing damage to the DNA of exposed cells) and carcinogenic (cancer causing). Those exposed usually suffer no immediate symptoms. Within 4 to 24 hours the exposure develops into deep, itching or burning blisters wherever the mustard contacted the skin; the eyes (if exposed) become sore and the eyelids swollen, possibly leading to conjunctivitis and blindness. According to the Medical Management of Chemical Casualties handbook, there have been experimental cases in humans where the patient has suffered miosis, or pinpointing of pupils, as a result of the cholinomimetic activity of mustard. At very high concentrations, if inhaled, it causes bleeding and blistering within the respiratory system, damaging the mucous membrane and causing pulmonary edema. Blister agent exposure over more than 50% body surface area is usually fatal.

--------------------------

you were correct in the fact that Phosgene was used as a weapon in WWI...

I'm sorry, but it Pssses me of to no end when people mix these two up... they are not the same, never have and never will

Grizzly
22-01-2008, 08:15 AM
WROOOOOOOONG!!!!!

Phosgene gas IS NOT the same as mustard gas...

Phosgene is a mix of chlorine and carbon monoxide. It is colorless and odorless and it attacks the lungs, causing edemas... simply put, it drowns you in your own body fluids....

----------------

Mustard gas is synthesized by treating sulfur dichloride with ethylene.

copied from wikipedia: Mustard gas is a strong vesicant (blister-causing agent). Due to its alkylating properties, it is also strongly mutagenic (causing damage to the DNA of exposed cells) and carcinogenic (cancer causing). Those exposed usually suffer no immediate symptoms. Within 4 to 24 hours the exposure develops into deep, itching or burning blisters wherever the mustard contacted the skin; the eyes (if exposed) become sore and the eyelids swollen, possibly leading to conjunctivitis and blindness. According to the Medical Management of Chemical Casualties handbook, there have been experimental cases in humans where the patient has suffered miosis, or pinpointing of pupils, as a result of the cholinomimetic activity of mustard. At very high concentrations, if inhaled, it causes bleeding and blistering within the respiratory system, damaging the mucous membrane and causing pulmonary edema. Blister agent exposure over more than 50% body surface area is usually fatal.

--------------------------

you were correct in the fact that Phosgene was used as a weapon in WWI...

I'm sorry, but it Pssses me of to no end when people mix these two up... they are not the same, never have and never will
Tyco
Many thanks for the info. I will never make that statement aka mustard gas again. I did not know it wan't and nor does / did any other syinkies I know!
It just proves the worth of the forum and that you are never to old to learn!
Cheers Grizzlyhttp://www.refrigeration-engineer.com/forums/images/icons/icon14.gif

grump
22-01-2008, 02:02 PM
Grizziy,Why traffic wardens, I worked in London 1962/2005 parking metres were introduced 1962 costing six old pence yes the old silver sixpenny piece for one hour by 2005 it was costing four pounds for one hour,maximum stay two hours.So when on a breakdown in central London, when no return was allowed to fill the meter it was best to pay for the maximum stay ,costing eight pounds.I carried a float of one hundred pounds in one pound coins.Now if you are on the roof of a high rise building,in the height of summer in central London under pressure to get the the system back on the air,while watching the clock to make sure you did not get an eighty pound parking fine,or a clamp which cost one hundred and twenty pounds plus the eighty pound fine,or return to find the vehile had been removed to a compound.The last time this happened to me was in Hackney,I went home that night by train returned the next day by train the cost excess of three hundred pounds to get my wheels back.Now this constitutes a danger to my sanity to the gangsters who control much of the parking in London,just go to one of the compounds to see for yourself the measures these craphats go to keep themselves safe. Grump :D:D:D

grump
22-01-2008, 02:55 PM
Hi again Grizzly,I see you have been put in your place re mustard gas,now i have experienced both ammonia and phosgene,there is no contest whatsoever phosgene stops you dead it its tracks,in the days when you let the refrigerant go, fired up the oxy-acetaline in a confined space, it was one of the fasted learning curves i ever experienced,ie one never to be repeated. Grump:D:D:D

Grizzly
23-01-2008, 10:22 PM
Hi again Grizzly,I see you have been put in your place re mustard gas,now i have experienced both ammonia and phosgene,there is no contest whatsoever phosgene stops you dead it its tracks,in the days when you let the refrigerant go, fired up the oxy-acetaline in a confined space, it was one of the fasted learning curves i ever experienced,ie one never to be repeated. Grump:D:D:D

Grump
Like I said before I presume you have kept your National Insurance Contributions up to-date?
I must of been lucky or cautous although I have been caught out by stale contaminated oil a couple of times. We will be reminising about the smell from halide torches next!
Grizzly

IceMan_4000
26-01-2008, 06:43 AM
Hi, hendry :)

I see, :D



....hope you got a chance to improve something there...maybe to replace the whole plant with ***** type;)

Best regards, Josip :)

Wow that is kind of miss directed. 20PPM of ammonia and most will not enter a room cause it is to harsh. a ***** plant that size with a big leak you can just go clean up the bodies when the leak is done. Because the human body can not tell how much ***** is in the air untill you go down from suffication.

Give me a NH3 plant any day

Josip
26-01-2008, 05:27 PM
Hi, IceMan_4000 :)

Welcome to RE forums...


Wow that is kind of miss directed. 20PPM of ammonia and most will not enter a room cause it is to harsh. a ***** plant that size with a big leak you can just go clean up the bodies when the leak is done. Because the human body can not tell how much ***** is in the air untill you go down from suffication.

Give me a NH3 plant any day

:) are you sure;)....this was a kind of "black humor" you should carefully read the whole thread...:rolleyes:....I'm definitely ammonia guy...

Best regards, Josip :)

IceMan_4000
01-02-2008, 11:31 PM
Hi, IceMan_4000 :)

Welcome to RE forums...



:) are you sure;)....this was a kind of "black humor" you should carefully read the whole thread...:rolleyes:....I'm definitely ammonia guy...

Best regards, Josip :)


Thanks Josip never said you were not a ammonia guy

Oh I read the thread, I was just trying to state the built in safety system NH3 has vs the displacement factor of the others.


I think I am going to have to slow my Typing down, I have already got a couple of neck fur's up


it must be my Canadian to euorpean dictonary.:D


IceMan_4000

Josip
02-02-2008, 12:09 AM
Hi, IceMan_4000 :)


Thanks Josip never said you were not a ammonia guy

Oh I read the thread, I was just trying to state the built in safety system NH3 has vs the displacement factor of the others.


I think I am going to have to slow my Typing down, I have already got a couple of neck fur's up


it must be my Canadian to euorpean dictonary.:D


IceMan_4000

No problem at all ;)....regarding typing down it is always nice if you (sorry, all of us) use a plain English...and make reading easier.....

....many times for many of us something is not very clear if you write in slang/phrases...
....english phraseology is not easy for english spoken people, but definitely is too hard for us:D)

Anyhow, you are a young man and you have a time to improve a lot of things;)

Best regards, Josip :)

US Iceman
02-02-2008, 12:19 AM
IceMan_4000,

I think it will also help if you watch for the emoticons used to convey a hint at the remarks left by posters. A lot of the posters here on the RE site have to translate their posts to their native language and will sometimes use the emoticons (to the right of the area where you compose the message) to add some "flavor" to their reply.

Sometimes a sense of humor is hard to interpret!:D

If I had to post messages in Croatian or Flemish my post count would be very small indeed.:o

IceMan_4000
02-02-2008, 01:34 AM
IceMan_4000,

I think it will also help if you watch for the emoticons used to convey a hint at the remarks left by posters. A lot of the posters here on the RE site have to translate their posts to their native language and will sometimes use the emoticons (to the right of the area where you compose the message) to add some "flavor" to their reply.

Sometimes a sense of humor is hard to interpret!:D

If I had to post messages in Croatian or Flemish my post count would be very small indeed.:o

that was not hard to interpret I laughed out loud or LOL

Grizzly
02-02-2008, 01:52 AM
Wow that is kind of miss directed. 20PPM of ammonia and most will not enter a room cause it is to harsh. a ***** plant that size with a big leak you can just go clean up the bodies when the leak is done. Because the human body can not tell how much ***** is in the air untill you go down from suffication.

Give me a NH3 plant any day
Iceman 4000.
Hey I get what you and Josip mean. may I put my take on what you are saying.
Using the extracted data below

"Permissible levels of exposure to toxic gases are defined by time-weighted average (TWA), short-term exposure limit (STEL), and concentration at which toxic gasses are immediately dangerous to life or health (IDLH). The TWA is defined as the concentration for an 8-hour workday of a 40-hour workweek that nearly all workers can be exposed to without adverse effects. Similarly, the STEL is the concentration to which an exposure of longer than 15 minutes is potentially dangerous and may produce immediate or chronic compromise to health. Anhydrous ammonia has a TWA of 25 ppm, an STEL of 35 ppm, and an IDLH of 500 ppm."
.................................................................
The impotant issue here is the fact that an exposure of up to 25ppm is allowed when deemed necessary for up to 8 hrs, Within a working week.
Useful when the Coldstore / Loading bay workers smell Ammonia. Useually from an oil purge or line purge being carried out in a nearby Plant room.
You then get all sort of protestations, like ah! I smell Ammonia and I can't work in this etc etc.
It was so bad in 1 Cold Store where I was Site Engineer that whenever there was the slightest whiff of Ammonia ( remember the human nose can smell from 0.9ppm the average being 5ppm). The site staff would "down tools" and refuse to work. What the managment did was obtain one of those clever "Gasman" Sniffers that analised the Ammonia concentration. Producing the written Union agreed data which basically said "Anything around 25ppm was acceptable for up to 8 hrs, as stated above.
The workforce were then limited as to when they could "cry wolf".
...........................................
People repeatedly exposed to ammonia may develop a tolerance (or acclimatization) to the irritating effects after a few weeks. Tolerance means that higher levels of exposure are required to produce effects earlier seen at lower concentrations.
.......................................
This just confirms all the "Old Timer Stories"
Like Old Pete never bothered with a resperator he would sit in the middle of a gas cloud smoking his pipe!
.......................................
One VERY IMPORTANT differance between Ammonia
And *****s is:-
Because Ammonia vapour is LIGHTER than air.
The use of a carbon filter resperator (type K1, K2 or K3) will aid breathing and enable safe retreat from the leak/ danger area.
Whereas HFC/ HCFC ( *****) CO2 or similar refrigerants are HEAVIER than Air.
Therefore a Fresh air or circulation Breathing mask (B.A.) MUST BE USED TO ENABLE MOVEMENT in the leak/ danger area.
So guys don't ever in panic grab your colleagues resperator and dive in to help your mate!!
Unless it is the correct type for the job.
Personally I have entered a plant room with full chemical suit and B.A. Waded through Liquid Ammonia
to the far end of a plant room. Shut off the offending
Oil pressure gauge ( the bordon tube had split internally). And yes it was a steel tube. Causing all the oil from the sump of a Grasso RC911 to spew out across the plant room floor. Followed by probably 200kg of vapour / liquid Ammonia.
It is a strange feeling in a Chemical Suit and B.A.wading through Liquid Ammonia. With very little vapour being given off because basically it freezes the surrounding areas it contacts so quickly that there is no heat to boil off the remaining liquid.
The only remaining heat source is your boots as you walk through it!
Once isolated it was just a case of carefully setting up a water curtain and letting the ammonia disolve in the water. What you do with the water then can be discussed another time.
Whilst this was going on I had an extremely nerveous young Site manager. Kitted out in full Chemical Suit and B.A. watching from the plant room door. With strict Instruction that should anything go wrong. He was to come in and get me!
Well he thought it would be clever to do the relevant B.A. Training as well as me.
Rest assured My suit became My Suit and he kept his PHEW!
SERIOUSLY THOUGH Guys. that could of been a nasty situation but with the correct training it was all dealt with safely.
God I need a drink now!
Cheers Grizzlyhttp://www.refrigeration-engineer.com/forums/images/icons/icon14.gif

nike123
02-02-2008, 11:39 AM
This article has some interesting points, maybe your (and others) attitude about risk with ammonia could change after reading it.;)

Article is found after 2 minutes surf of results in Google search with terms "refrigerant death statistic".

Site is: http://tinyurl.com/35m922

http://www.fluorocarbons.org/design/images/inner_content_top.jpg http://www.fluorocarbons.org/design/images/spacer.gif
Accidents with refrigeration fluids http://www.fluorocarbons.org/design/images/spacer.gif
Due to number of accidents with ammonia or hydrocarbons, it is necessary to look in detail at the risks associated with their use. This aspect is even more important for developing countries, because of situations like uneven maintenance, unreliable power supplies, climate conditions /Ref 1998 - ch. 12.7/.
Although sound safety training and controls might help, the extra cost needed to ensure a high health and safety level for using toxic or highly explosive material (in some cases plants have been totally destroyed) should also be taken into account.

A Working Party on Refrigerant System Safety has been set up by the International Institute For Refrigeration (http://www.iifiir.org/) (IIR). Indeed, although some refrigerants have been in use for 100 years, very little documented experience exists, which makes safety assessment an issue, and therefore safety standard a challenge. IIR also considers the interest for correlating existing safety requests with experienced accidents. The Working Party aim is to document the expertise gathered by experienced engineers and to record it in an objective way. For all types of systems and all refrigerants the real number of accidents should be investigated, and a database be set up for accidents involving injuries to humans and property damages.
Source : http://www.iifiir.org/telecharg/safety.pdf http://www.fluorocarbons.org/images/ic%C3%B4ne_pdf.gif
Accidents in refrigeration applications
The use of hydrocarbons and ammonia is often considered as safe, provided stringent safety measures and standards are followed. Such statements are based on risks assessments (example /Ref 1999/ Ch. 9.2.4 about hydrocarbons in road transport). However, these risk assessments are only theoretical. An IEA study / (http://www.fluorocarbons.org/applications/refrigeration/tech_safety/#ref2)Berg 1994/ (http://www.fluorocarbons.org/en/debate/safety_aspects/references_on_refrigeration_fluids_and_safety.html) concluded that a VROM (NL) ammonia calculated risk assessment lead to a risk of deaths "10-100 times smaller than those observed.
Accidents involving ammonia

There are several reports on accidents involving ammonia/ (http://www.fluorocarbons.org/applications/refrigeration/tech_safety/#ref2)CDCIR 1992/ /Berg 1994/ Amm 1995/ (http://www.fluorocarbons.org/en/debate/safety_aspects/references_on_refrigeration_fluids_and_safety.html) / which conclude that it is difficult to collect data on all the accidents that occur. Unep 1998 (http://www.fluorocarbons.org/en/debate/safety_aspects/references_on_refrigeration_fluids_and_safety.html) compiled a list of significant accidents which contains 18 ammonia accidents.
Amm 2002 (http://www.fluorocarbons.org/en/debate/safety_aspects/references_on_refrigeration_fluids_and_safety.html)/ makes a comprehensive analysis of more than 400 accidents involving ammonia between 1992 and 2001, wherefrom 109 involved ammonia. Most (but not all) of the accidents involving “Other refrigerants” actually were the consequence of a fire, rather than a leakage.
"Working Fluid Safety"/ (http://www.fluorocarbons.org/applications/refrigeration/tech_safety/#ref2)Berg 1994 (http://www.fluorocarbons.org/en/debate/safety_aspects/references_on_refrigeration_fluids_and_safety.html)/ (http://www.fluorocarbons.org/applications/refrigeration/tech_safety/#ref2) has used statistics on ammonia refrigeration accidents to derive probabilities of ammonia accidents. We have applied these probabilities to a Dutch proposal /Eco 1998/ (http://www.fluorocarbons.org/en/debate/safety_aspects/references_on_refrigeration_fluids_and_safety.html) to switch to ammonia 70 000 refrigeration systems by 2010 (instead of 150 today). The results presented in Table 5 are striking - for a population of only 15 million.

Kind of risk
Frequency
NL Probability (70 000 units)
Death
1 x 10-4
7 per year
Injury
10-30 x 10-4
70 - 210 per year
Accident
10-150 x 10-4
70 – 1 050 per year
Ammonia Risk Assessment applied to the Netherlands /Berg 94/ /Eco 98/

These risks are specially valid for smaller units, because large ammonia refrigeration units are usually surveyed 24 hours a day. For the large number of users of smaller refrigeration units, this will most often not be the case, since many units are left unattended for long periods of time.
Due to millions of refrigeration equipment world-wide including developing countries, we think that lives and environment will be better protected by not introducing ammonia outside its traditional uses.
Accidents involving Hydrocarbons

Since refrigeration accidents are due to equipment failure, poor maintenance or human factors, there is no reason to expect different accident frequencies, except that the toxicity risk would be replaced by fire and explosion risk of a hydrocarbon leakage, which can have a significant destructive force.
Again the number of installations should be kept in mind : the same Dutch report /Eco 98/ (http://www.fluorocarbons.org/en/debate/safety_aspects/references_on_refrigeration_fluids_and_safety.html) suggests switching to hydrocarbons by 2010 a number of 295.000 units containing 1 to 30 kg refrigerant, of 10.000 units containing more than 50 kg. Bearing in mind that the explosion of 1 kg hydrocarbon releases the same energy as 1 kg of TNT, we wonder if this change should not be promoted with more care for human or property losses.
The report /IIR 97/ (http://www.fluorocarbons.org/en/debate/safety_aspects/references_on_refrigeration_fluids_and_safety.html) concludes that "Expanding the use of flammable refrigerants [..] changes past safety practices and should be done with great care to ensure that the safety of the public is maintained."
Accidents involving Fluorocarbons
There is also little published data for risks related to HFCs, but some is available on use of CFCs and HCFCs. These have led to some fatalities over the years, mainly due to suffocation. This is a risk with any inert gas; e.g. engineers have died in confined areas that are full of refrigerant vapour. The number of fatalities reported is far lower than for ammonia systems, even though there are significantly more FC systems in use. The risk of fatalities with FCs is several orders of magnitude lower than for ammonia (Berg 1994).

Grizzly
02-02-2008, 11:45 AM
nike 123.
And in in your own words, Your point is?
Grizzly

rkmoorthy
02-02-2008, 11:46 AM
hai guys i am new for this site, anybody can you send me service manual of carrier container chiller and freezer

nike123
02-02-2008, 11:59 AM
nike 123.
And in in your own words, Your point is?
Grizzly
Maybe I am wrong, but reading articles here on RE about amonia my impression is that lot of ammonia guys think, that is safer to work with ammonia, because they could smell it, than with fluorocarbons. I was trying to add statistic to that perspective.

Maybe, I shouldn't reply to your post, yet, I have needed only respond to this thread. :o

Grizzly
02-02-2008, 12:27 PM
Nike
Thanks I now understand the point you are trying to make.
I do view Ammonia as safer BUT only in the fact that The dangers of Ammonia are more obvious than *****s. There for People approach it with caution thinking about their Helth and Safety.
No I don't think its safer than *****s BUT PEOPLE ADOPT A SAFER WORKING ATTITUDE TOWARDS IT, because the dangers are more obvious.
Because of these dangers I take more precautions when working with Ammonia than I might sometimes with *****s.
Therefore because of that point I sometimes state that ***** is more dangerous because it is taken for granted more often! Not because it actually is.
Grizzly

Josip
02-02-2008, 01:08 PM
Hi, nike123 :)


Maybe I am wrong, but reading articles here on RE about amonia my impression is that lot of ammonia guys think, that is safer to work with ammonia, because they could smell it, than with fluorocarbons. I was trying to add statistic to that perspective.

Maybe, I shouldn't reply to your post, yet, I have needed only respond to this thread. :o

Seems we all make a little mess here;)

No you are not wrong.....your impression is ok, but that has no meaning it is safer to work with ammonia ....NO...definitely NOT safer......it is very very dangerous ....(by smell we only have an early warning) and only trained persons should attempt to do repairs or whatever......

.....work with ammonia is more dangerous then work with fluorocarbons what does not mean they are harmless.... .......there is no safety refrigerant...

it is only a question about different attitude when approaching to problem ......with ammonia I am always at red alert.......


No I don't think its safer than *****s BUT PEOPLE ADOPT A SAFER WORKING ATTITUDE TOWARDS IT, because the dangers are more obvious.
Because of these dangers I take more precautions when working with Ammonia than I might sometimes with *****s.

seems Grizzly explain that much better;)

Best regards, Josip :)

nike123
02-02-2008, 01:23 PM
Nike
Thanks I now understand the point you are trying to make.
I do view Ammonia as safer BUT only in the fact that The dangers of Ammonia are more obvious than *****s. There for People approach it with caution thinking about their Helth and Safety.
No I don't think its safer than *****s BUT PEOPLE ADOPT A SAFER WORKING ATTITUDE TOWARDS IT, because the dangers are more obvious.
Because of these dangers I take more precautions when working with Ammonia than I might sometimes with *****s.
Therefore because of that point I sometimes state that ***** is more dangerous because it is taken for granted more often! Not because it actually is.
Grizzly


I totally understand you. I am electrician, and when I work with electrical equipment or installations I always disconnect them from power source. What could be safer than electrical equipment without electricity in them.
But peoples are prone to make mistakes and some things are more deadlier than other when you make mistake, no matter of all precautions.

So, my advice is, regardless you work with ammonia or fluorocarbons, be aware of electrical current and fools!:D:D

Grizzly
02-02-2008, 03:31 PM
I totally understand you. I am electrician, and when I work with electrical equipment or installations I always disconnect them from power source. What could be safer than electrical equipment without electricity in them.
But peoples are prone to make mistakes and some things are more deadlier than other when you make mistake, no matter of all precautions.

So, my advice is, regardless you work with ammonia or fluorocarbons, be aware of electrical current and fools!:D:D

Using the Viking Edict....
We all agree then care should be taken ALLWAYS!
But it dosn't hurt to remind each other occationally does it!
Grizzlyhttp://www.refrigeration-engineer.com/forums/images/icons/icon14.gif

US Iceman
02-02-2008, 08:52 PM
If there are any beginners out there, they should be reading this thread and the material linked in the posts....

Josip said it best. There are no safe refrigerants. And when working on any refrigerant system you should be on red alert. Things happen when they are least expected.;)

Buckiesr
12-02-2008, 05:29 AM
I am being told several different facts by those wishing to sell me compressors for my new cascade co2/ nh3 system. screw compressors slip and are not efficient for co2 and that screws are more efficient than recipts period. I here most if not all co2 systems in the UK use recips. Nestles built a cascade system in the US, it is considered to be a flop because while it works fine it is very inefficient. I am going to CA this weekend to visit an operating warehouse there and attend their open house. Both companies swear by their systems. Who has information to support one or the other or both? I ask the recip supporter why do you install recipts? he said the molecular weight of co2 is 44, nh3 is 17, co2 is more than 10 times heavier, I thought 17X10 =170 but maybe it isn't the same as regular math more like the rector scale earthquakes are rated on, each number is way more severe not just a little stronger. The other company's refrigeration guy is from Denmark, he seemed fine with a Mycom screw. He wants to fly us to Japan to visit the manufacturing plant and the new Wal-mart facility in operation. What say you all?

Dan
13-02-2008, 05:14 AM
If you are referring to the Savannah, Ga Sam's club, I toured it prior to Grand Opening. I was favorably impressed with the installation, and the performance. The R404a rack was operating at about a -19 deg F suction which is comparable to direct expansion Sam's Clubs. The energy consumption is being monitored by a disinterested third party, as are some other installations of CO2 circulating supermarkets.

I haven't seen any of the audit results, which makes me wonder if the energy usage is not as good. If Walmart has a cold storage combo with CO2 and Ammonia, it lends credibility to circulating CO2 as a brine/refrigerant.

The MG Pony
21-02-2008, 02:50 PM
I would much sooner have a hydrocarbon plant or an Amonia plant next to my home then any other! The hydrocarbon will sort its self out in quick order over the ground, and in fire it will simply flare off with little left over products of burning.

As with amonia, and in a leak I will smell it long befor there is danger, or in big leak a wet rag will get me to a safe area.

But with HFCs HCFCs, there will be little escap in event of fire, it will poisen the air in such a way that no simple wet rag will get you to safety as it flairs off, a larg leak will not be knoticed with out electrical sensors befor it is too late.

The oil we use is flammible all ready thus fire risk is a weak excuse, the toxicity of the byproducts makes toxicity a poor excuse. So in the end my trust lies with HC and NH3!

Lazarus
21-02-2008, 04:29 PM
The simple answer to all queiries on ammonia

from a commisioning / trouble shooting perspective

----try to align an open drive compressor with sparky jumping up and down on pack

let loose a little ammonia .... and smile while he runs out the door, whistle and finish up

PaulZ
22-02-2008, 08:51 AM
Hi Lazarus
That works well with clients who want to watch everything you do.
Good trick is if they are hanging around get them to give you a lift with a head or side cover, one good wiff and I bet you don't see them for a while.
Paul

Refrigerologist
11-03-2008, 12:25 AM
Try this one. The maintenance guy at our local dairy, well the only dairy, this is a small island. He used to cut an opening about 2 to 3" sq into the side of an old 1 gallon metal oil can. Put the lid on and then purge a little Ammonia into the can. After which he would take a liquid dropper and drip one small drop of water through the opening. The can would collapse in on itself!

Oregon Jim
11-03-2008, 03:02 AM
I have worked with ammonia for more than twenty years now and still deal with it every day. I have about 20,000 pounds of ammonia in my small system. I'd like to address the original topic of NH3 "finding" the water in the bucket. Every expert will tell you ammonia is drawn to moisture, and given the right circumstance NH3 vapor will in fact "find" water. It isn't magic or even a fairy tale. I am certain the story was highly embellished to awe the novice, but it was based upon well documented fact. Ammonia likes water.

I have been a refrigeration engineer for more than 20 years and I am trained as a HazMat responder to deal with ammonia releases, and frankly I find it to be terribly exciting more than anything. Ammonia isn't the boogie man everyone makes it out to be. I'll be rebuilding NH3 pumps and valves, replacing old pipe, moving thousands of pounds of ammonia around the system , and giving my compressors a good going over during the next few weeks before production.

I LIKE AMMONIA!

Contactor
13-03-2008, 03:24 PM
Hell yeah!

Greengrocer
26-04-2008, 10:25 PM
In the early 70's I used to attend Willesden Tech (London) as part of my Frigidaire apprenticeship. A guy in my class worked for the Lyons Maid ice cream factory / distribution centre in Greenford - Big NH3 system.
We could smell this guy coming down the hall before we saw him. In class he was "billy no mates" because no one wanted to sit next to him and he continually scratched his "crown jewels". Come break time we'd go to the canteen and this guy had to have 6 spoons of coffee and 8 sugars in his drink before he could taste it. Boy was I glad that Frididaire didn't make any NH3 plant.

US Iceman
27-04-2008, 02:27 AM
In the early 70's I used to attend Willesden Tech (London) as part of my Frigidaire apprenticeship. A guy in my class worked for the Lyons Maid ice cream factory / distribution centre in Greenford - Big NH3 system.
We could smell this guy coming down the hall before we saw him. In class he was "billy no mates" because no one wanted to sit next to him and he continually scratched his "crown jewels". Come break time we'd go to the canteen and this guy had to have 6 spoons of coffee and 8 sugars in his drink before he could taste it. Boy was I glad that Frididaire didn't make any NH3 plant.

I don't see where this has anything to do with ammonia systems other than the scratching the crown jewels part. Sweat and ammonia makes for an interesting case of diaper rash in the summer.

Other than that, the rest is guilt by association.

Sergei
27-04-2008, 06:55 PM
In the early 70's I used to attend Willesden Tech (London) as part of my Frigidaire apprenticeship. A guy in my class worked for the Lyons Maid ice cream factory / distribution centre in Greenford - Big NH3 system.
We could smell this guy coming down the hall before we saw him. In class he was "billy no mates" because no one wanted to sit next to him and he continually scratched his "crown jewels". Come break time we'd go to the canteen and this guy had to have 6 spoons of coffee and 8 sugars in his drink before he could taste it. Boy was I glad that Frididaire didn't make any NH3 plant.
Probably, he didn't have shower for a few weeks. Any connections with ammonia refrigeration plant?

Grizzly
28-04-2008, 02:13 PM
In the early 70's I used to attend Willesden Tech (London) as part of my Frigidaire apprenticeship. A guy in my class worked for the Lyons Maid ice cream factory / distribution centre in Greenford - Big NH3 system.
We could smell this guy coming down the hall before we saw him. In class he was "billy no mates" because no one wanted to sit next to him and he continually scratched his "crown jewels". Come break time we'd go to the canteen and this guy had to have 6 spoons of coffee and 8 sugars in his drink before he could taste it. Boy was I glad that Frididaire didn't make any NH3 plant.

I liked the comment Greengrocer, how many of us older "Stinkies" have stood in a plant room smelling of Ammonia.
And said to the new trainee "smell! what smell?"
My wife goes nuts for days after I have used my purge lines and returned them to the car.
She sometimes forgets that it is my working vehicle.
Grizzly

nubbin
01-05-2008, 04:54 AM
it's not the refrigerant that is dangerous, it is the idiot with the wrench. Rented a house with a Arkla gas AC, called landlord for service. he called his company for service. When the idiot could not solve the problem, he stuck a tube of lip balm under the sail switch. I noticed the safety violation and called the land lord but he had already paid for the "service".
I think NH3 is safer. NH3 is not used in the local residential market leaving R22 and the like. Sometimes I run into R22 that pops-out of an oil trap when brazing. Hate that, because I know what it does.

hendry
18-05-2008, 06:06 AM
haven't been there lately ...
hearsay, they found cheaper refrigeration "specialist" ...

we move on ... with dignity!

yeah .. i've news on their latest leakages.
last friday!

this round from an abandoned northstar ice machine!

anyway, i only observe from as far as 100km away.

Hendry, on wesak day holiday.

Grizzly
29-05-2008, 10:53 PM
Your never too old to learn!
Whilst purging off a faulty EVRA 20 (Hot Gas Line Solenoid Valve).
I managed to find a little pocket of liquid Ammonia which sprayed out,when I broke the seal between the armature and body.

No problem I thought as I was prepared and had carefully loosened the bolts, diagonally.
So whilst holding my breath I snapped shut the valve and made a Hasty retreat to-wards the plant room door.

Having reached the safety of the fresh air outside the plant room. I took a big gulp of Air.

About the same time as I realised that the fresh air stank of Ammonia, a precious part of my anatomy started to burn. Burn maybe not, but it was getting rather warm in that region!

Only then did it dawn on me that the stream of liquid Ammonia had saturated
the waistband of my overalls.
Which now having found a heat source was boiling off.
So instead of fresh air I was breathing high concentrations of Ammonia vapour.

By this time the 2 site engineers that had led the rapid Exodus from the plant room.

Were doubled up in laughter at the sight of yours truly jumping up and down gasping for air.
Whilst trying to rip my overalls off!!
I did laugh eventually once I had got my breath back.
Despite this minor setback. The valve was fixed (which had a perforated diaphragm).

And the Engineers gave me a nice bag of Crabs Claws packed in ice for supper. (It's a Ice Plant!)

Grizzly

TXiceman
30-05-2008, 04:42 AM
Reminds me of a like experience about 30 years ago. A technician and I were bleeding down a line section is a closed engine room, exhaust fans running max speed, and we had on the ammonia mask to go in and break the control valve loose after the line was depressurized (mostly). It was August in North Carolina and hotter than hades. About the same time we both dropped the wrenches and bailed out, headed to the emergency shower and were fighting as to who got to strip the overalls and save the "family jewels" first. I was the large one and got the shower, the tech, dragged a box over and was cooling himself in the emergency eye wash.

We got a big whoopie from the ladies on break at the back dock. Working with ammonia is so interesting...no telling what you will have to do day to day.

Ken

Grizzly
30-05-2008, 05:19 PM
Reminds me of a like experience about 30 years ago. A technician and I were bleeding down a line section is a closed engine room, exhaust fans running max speed, and we had on the ammonia mask to go in and break the control valve loose after the line was depressurized (mostly). It was August in North Carolina and hotter than hades. About the same time we both dropped the wrenches and bailed out, headed to the emergency shower and were fighting as to who got to strip the overalls and save the "family jewels" first. I was the large one and got the shower, the tech, dragged a box over and was cooling himself in the emergency eye wash.

We got a big whoopie from the ladies on break at the back dock. Working with ammonia is so interesting...no telling what you will have to do day to day.

Ken

"Ken" is Scottish slang for understand and as they say you have been there and had the teeshirt Iceman.

Yep!
It can be interesting and I am sure there are lots of the guys out there that can relate to both stories?

I just posted it because it's yet another amusing story.
With a happy ending!
Grizzly

ArthurLeigh
29-08-2008, 12:26 PM
WROOOOOOOONG!!!!!

Phosgene gas IS NOT the same as mustard gas...

Phosgene is a mix of chlorine and carbon monoxide. It is colorless and odorless and it attacks the lungs, causing edemas... simply put, it drowns you in your own body fluids....

----------------

Mustard gas is synthesized by treating sulfur dichloride with ethylene.

copied from wikipedia: Mustard gas is a strong vesicant (blister-causing agent). Due to its alkylating properties, it is also strongly mutagenic (causing damage to the DNA of exposed cells) and carcinogenic (cancer causing). Those exposed usually suffer no immediate symptoms. Within 4 to 24 hours the exposure develops into deep, itching or burning blisters wherever the mustard contacted the skin; the eyes (if exposed) become sore and the eyelids swollen, possibly leading to conjunctivitis and blindness. According to the Medical Management of Chemical Casualties handbook, there have been experimental cases in humans where the patient has suffered miosis, or pinpointing of pupils, as a result of the cholinomimetic activity of mustard. At very high concentrations, if inhaled, it causes bleeding and blistering within the respiratory system, damaging the mucous membrane and causing pulmonary edema. Blister agent exposure over more than 50% body surface area is usually fatal.

--------------------------

you were correct in the fact that Phosgene was used as a weapon in WWI...

I'm sorry, but it Pssses me of to no end when people mix these two up... they are not the same, never have and never will
Whilst you are of course correct to say that Mustard gas and Phosgene are not the same, unfortunately, you accidently omitted the words "made from" :
Phosgene is carbonyl chloride, [COCl2] , it can be made from a mixture of chlorine [Cl2] and carbon monoxide [CO]. Mustard Gas is ββ'-Dichloroethyl Sulphide, [ (ClCH2.CH2)2S ] and as you stated, can be made from ethylene [CH2:CH2] and Sulphur dichloride [S2Cl2] .

Tycho
29-08-2008, 03:11 PM
Whilst you are of course correct to say that Mustard gas and Phosgene are not the same, unfortunately, you accidently omitted the words "made from" :
Phosgene is carbonyl chloride, [COCl2] , it can be made from a mixture of chlorine [Cl2] and carbon monoxide [CO]. Mustard Gas is ββ'-Dichloroethyl Sulphide, [ (ClCH2.CH2)2S ] and as you stated, can be made from ethylene [CH2:CH2] and Sulphur dichloride [S2Cl2] .



pfffft...

:D:o