Merged: Oxygen tanks topped up with Nitrogen

[chockchucker]

Perhaps another good reason why LAME's should not be reduced in numbers on the tarmac....................


Probe after Qantas pumps wrong gas into jets
Matthew Benns
December 16, 2007

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POTENTIALLY fatal gas being pumped into passenger jet emergency oxygen tanks in Australia has sparked a worldwide safety investigation.

The Australian Safety Transport Bureau confirmed yesterday that Qantas engineers accidentally put nitrogen into the emergency oxygen tanks of a Boeing 747 passenger jet at Melbourne Airport.

The Australian carrier immediately checked the oxygen supplies of more than 50 of its planes that had been serviced by the mislabelled nitrogen cart at the airport. But an aviation source said: "This could have affected hundreds of planes worldwide. Any international jet that passed through Melbourne and was serviced by Qantas could have had nitrogen pumped into its oxygen tanks."

Health experts warned that in an emergency the effects of nitrogen in the oxygen tanks could have potentially fatal results.

Dr Ian Millar, hyperbaric medicine unit director at The Alfred hospital, said: "If there was an emergency and the pilot took nitrogen instead of oxygen, instead of gaining control of the aircraft he would black out and it would be all over. It's a pretty serious mistake."

Nitrogen, which is non-flammable, is commonly used at airports to fill aircraft tyres. The aviation source said: "Qantas took delivery of the new nitrogen cart 10 months ago. It looked exactly like the old oxygen cart. When the attachments did not fit they went and took them off the old oxygen cart and started using it."

The mistake was eventually spotted by an aircraft engineer. "He was walking around the plane and asked what they were doing. When they said they were topping up the oxygen, he said, 'No you're not, that's a nitrogen cart'," said the source.

The incident was reported to the Civil Aviation Safety Bureau, which confirmed that an investigation detected nitrogen in the crew oxygen tanks on the Boeing 747-300. A bureau spokeswoman said it was a one-off incident.

But the aviation source said: "This has affected at least 175 planes and Qantas has had to tell any other airline that has been serviced in Melbourne to check out its oxygen supplies."

Air New Zealand was told about the problem six weeks ago. "As a result of receiving that letter we did take some precautionary measures," a spokeswoman said. "The oxygen tanks on a small number of planes were removed, checked, reserviced and refilled. No irregularities were found."

A spokeswoman for the Australian Transport Safety Bureau said: "Very clearly they (Qantas) needed to carry out a risk assessment because there was a chance that other aircraft were affected.

"They identified 21 that were at risk because they had had a reasonable amount of oxygen top-up, so there was a reasonable chance they had been contaminated. There were another 30 aircraft at minor risk because they have had minor top ups," said the spokeswoman. The planes were inspected and no positive results found.

She said the airline had turned the error into a learning exercise and informed engineers all over the world about the mistake. "They have talked to thousands of their engineers around Australia and overseas, informing them about this lesson that has been learnt," she said.

Qantas engineering executive general manager David Cox said: "We had a guy using a new rig and he inadvertently serviced the crew oxygen with nitrogen. He realised what he was doing and flagged it."

Mr Cox said that once the mistake had been realised, extensive safety checks were put in place to ensure no other aircraft had been contaminated and that it could never happen again.

"Every aircraft, including customer aircraft, that could have been touched with this rig has been checked," he said after confirming the rig had been in use at the airport for several months. Mr Cox said the airline had been completely open in informing all safety authorities, staff and other airlines about the mistake.


This story was found at: http://www.theage.com.au/articles/2007/12/15/1197568332267.html

[the shaman]

I have heard that a QF 747 at Tulla had Oxy tanks topped up with Dry Nitro gas.... I can feel my eye balls bulging already... how can this happen... in my time at QE oxy carts were painted white and very clearly distinguishable from the Nitros which were red.....

[whatdouknow]

Heard this one, doesn't sound good, not sure how you could miss the bottle identification...

duhh

:ugh::ugh:

[whatdouknow]

There is an earlier post about the same issue, newspaper story included.

Please do not use this one, only a few minutes apart!!

[Howard Hughes]

Assuming they used it in flight, would it be possible to get 'nitrogen narcosis' at altitude?:eek:

PS: This one is better titled to arouse interest!;)

[whatdouknow]

HH Yes true, who can delete the other or lock it!!

Just more info in the other one...

[the shaman]

Sorry about that - did not mean to hijack another post - however it is a really serious issue that deserves a specific subject heading ...

[chockchucker]

Maybe, but are you sure about the qualifications of those who were servicing the oxygen system with the nitrogen cart?


Not that I'm a big fan of the abolition of FE's either! After all, most of them are ex LAME's:ok:

[Desert Duck]

Basic safety procedures should ensure that nitrogen fittings do not fit oxygen bottles.

[Desert Dingo]

From original article:
"Qantas took delivery of the new nitrogen cart 10 months ago. It looked exactly like the old oxygen cart. When the attachments did not fit they went and took them off the old oxygen cart and started using it."

[the shaman]

So who were the 'industry professionals' who scoped out and oversighted the design of the new carts .......? did they consider 'human factors' issues ie. the new nitro carts should be clearly distinguishable from the new oxy carts... what about risk assessments and training on the new equipment... did a breakdown of 'due process' cause this..??

[Howard Hughes]

Nice buzz words Shaman, but whatever happened to good old fashioned common sense? It seems to have been bogged down in a quagmire of arse covering!:rolleyes:

[the shaman]

Thats a fair call Howard..... it is just such a bad stuff up with potenial catastrophic results ... I am really wondering how so many holes in the swiss cheese lined up,,,, lucky the last one did not ie. rapid depresurisation of the cabin at altitude..

[Blip]

Dr Ian Millar, hyperbaric medicine unit director at The Alfred hospital, said: "If there was an emergency and the pilot took nitrogen instead of oxygen, instead of gaining control of the aircraft he would black out and it would be all over. It's a pretty serious mistake."

Is Dr Millar assuming the tanks were 100% full of Nitrogen?

When oxygen tanks are serviced, are they not simply topped up? Therefore would it not be fair to say that the tanks would be something like 95% Oxygen, and 5% Nitrogen?

Considering air is 78% Nitrogen, and 21% Oxygen, perhaps claiming that instant death would be inevitable is overstating it somewhat.

Of course I am not saying it is a serious matter, of course it is! I'm just pointing out that it may not be AS bad as first thought. (The partial pressure of oxygen is still 95% of what it would have been had it been serviced with oxygen bottles).

http://en.wikipedia.org/wiki/Earth's_atmosphere

[Mr.Buzzy]

I'd like to know which "passenger" oxygen system can be topped up by a cart.

I'm all for saving engineering jobs but this leak has done little for the LAME jobs cause. Public perception of QF engineers over this nitrogen incident is not particularly sympathetic. In fact reaction has been to ask if you blokes know what you are doing. Hate to think if the same bloke had tried to service an oleo with oxygen!!!!!!!!

If you're going to make your point around Christmas time, at least pick a fight that makes you look good an will get Joe public on side.

bbbbbbbbbbbbbbbbbbbbbbbbbbbzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz z

[qf_conehead]

Buzzy.
passenger oxy on the 747 is from bottles, not chemical generators. its serviced via the same fill port as the crew oxy is.

[the shaman]

the old type of oxy and nitro carts used by QE were well marked and virtually impossible to confuse.... I am still puzzled as to how a 'new' nitro cart can be introduced into QE that can in anyway be confused / used for oxy servicing.....?? I think the persons responsible for commissioning and risk assessing this equipment may be a little red faced at the moment.

[whitenite]

HH
common sense is a wonderful concept, it's just not very common these days.

[satos]

Aren't the fittings of the oxy bottles different from the ones on the nitrogen so you cant mix them up.

[tail wheel]

Is the gas label on the bottles visible when the bottles are on the cart? If so, would someone not notice "Oxygen" is not spelt N-i-t-r-o-g-e-n? :confused:

[NAS1801]

Oxy cart bottles are black.

Nitrogen cart bottles are grey

I have an idea. How about QF paint the whole oxy cart green? (aircraft bottles being green).

Oops... lean smegma mite steal that idea off me and someone may use it to get their purple belt.

[Wiley]

So who were the 'industry professionals' who scoped out and oversighted the design of the new carts .......? did they consider 'human factors' issues ie. the new nitro carts should be clearly distinguishable from the new oxy carts... what about risk assessments and training on the new equipment... did a breakdown of 'due process' cause this..??sharman, the answer to your question is so blindingly obvious I'm surprised you didn't answer it yourself.

Readers just need a translation to modern day aviation-speak.

- "industry professionals" = beancounters
- "due process" = cheapest quote
- "risk management/assessment" = cheapest option/procedure

There... it's simple when you speak the language, isn't it?


***

Since the mistake was found before the proverbial hole in Dr Reason's last slice of cheese lined up with some hapless crew suffering an decompression or a cabin fire, I suppose we should be grateful that the original mistake was getting a nitrogen cart confused with an oxygen cart and not the other way around. Had it been the other way around, there could have been a major explosion had some unfortunate LAME tried working on the cart with a greasy spanner - or, as someone has mentioned already, if someone had tried using oxygen to fill an undercarriage oleo.

[Sunfish]

if someone had tried using oxygen to fill an undercarriage oleo.

That thought makes my hair stand on end. How does an exploding oleo on full compression on touch down sound?

As for "Nitrogen Narcosis", nope, you would need to be breathing normal strength air in an atmospheric pressure of about 60PSI to get whoopsy.

[TinKicker]

Having worked in the medical area in a past life, this sort of thing would not have happened if they took the lessons learnt from medicine. A long time ago, Doctors discovered that if you fill a patient up with the incorrect gas, the results were not conducive for a long life. Following some investigation they came up with the idea that if you make each gas fitting unique, then the possibility of placing the wrong gas in the wrong area was removed from the equation. As a result, oxygen cylinders can not be connected to CO2 cylinders because the collar is different. It is the same with nitrogen and the other gases found in hospitals. Anaesthetic gases work along a similar line when added to the anaesthetic machine.
The question I ask is "How difficult would it be to have unique fittings for each gas cylinder?" I know of nitrogen and oxygen being used in an aircraft, but are they any other ones? Maybe the gingerbeers out there can help.
Tinkicker

[Milt]

Wrong Gas leads to thread creep.

Good one for the Mythbusters.

Will an oleo disintegrate if some idiot tries to pressurize it with oxygen?

And what are the consequences of filling a tyre with oxygen?

And how about the fuel cells that are nitrogen purged?

Some interesting stories may be about to come to light.

Murphy's Law says it will happen!

[prospector]

NITROGEN USED TO FILL AIRCRAFT OXYGEN SYSTEMS
Airlines all over the world are being warned to check to make sure there’s actually oxygen in their aircraft oxygen systems after an embarrassing mix-up by Qantas Airlines at Melbourne International Airport. For ten months, crews have been filling airliner oxygen systems from a nitrogen cart that’s supposed to be used to fill tires. The mistake went unnoticed until a couple of weeks ago when an observant aircraft engineer spotted service workers using the cart. "He was walking around the plane and asked what they were doing. When they said they were topping up the oxygen, he said, 'No you're not, that's a nitrogen cart,'" an unnamed source told The Age. As anyone who works with industrial gases knows, oxygen tanks have different fittings than other gases to prevent exactly this kind of mix-up. However, when the crews discovered the fittings on what they thought was their new oxygen cart didn’t fit, they swapped them for the ones on the old cart they were retiring. Of course, Australian officials are looking into the error and Qantas has been busy notifying other airlines that use its services in Melbourne. Hundreds of aircraft may be affected.

[magoo31]

The carts were designed by LAME's, for LAME's and IAW the relevant standards, i.e. colour coding etc.
Extensive consultation was carried out across the network with involvement of both trades.
No they weren't the cheapest or easiest option. They took a hell of a lot of frigging around to get right.
The cheapest and easiest would have been an off the shelf product which didn't meet our requirements so far as ease of use, safety and maintenance.
The carts are coloured coded differently.
The bottles are still grey for nitro, black for oxy.
The fittings are still different between carts.
The only possible deficiency may have been in the implementation and training stage in Mel, but that is purely speculation.

I hate to say it, but it could have just been a monumental brain explosion.

[Short_Circuit]

The difference between grubby scratched grey or black cylinders at night, when raining, in blinding sun, under time constraints with a good level of fatigue etc, etc, etc…. It’s gunna happen.

As stated before, why not paint the cylinders green or the carts green (even easier), it will now be obvious at a great distance to all.


Talk to CASA & BOC, stop the holes in the cheese aligning now.

[NAS1801]

Some important points.

1)The fittings are different between oxy and nitrogen systems as stated several times already. SO TO ALL THOSE WHO KEEP SUGGESTING THIS, STOP IT. IT HAS BEEN MENTIONED HERE OVER AND OVER AND OVER.

2)Different coloured bottles... different shut off valve and regulator arrangements on the carts. If even basic training had been given, those involved should have known immediately that they were using the wrong cart.

3)Potentially fatal? Highly unlikely. An oxy system is never completely filled and therefore, there is no chance that the system would contain pure nitrogen or even a high percentage. If the system is showing empty, bottles are REPLACED with FULL bottles from stores. Those bottle would have been filled in the oxygen shop in component maintenance.

Normally, you would only have to add around 100-300PSI to the system. Off the top of my head, 1850PSI is the aprox. system pressure. 300PSI represents 16% of the total pressure.
The air we breathe is aprox. 78% nitrogen and 21% oxygen. In order for a potentially fatal level of nitrogen to be added, the aircrafts system pressure would have to have been considerably less than 380PSI!!!!!!!!!! If this were the case, It would indicate a major leak in the system and considerable troubleshooting would be carried out.

To say that this was a potentially fatal incident is just scare mongering. Far more potentially fatal would be filling a landing gear strut with oxygen due to the presence of oil and yes, this did happen im Melbourne once too.

Despite the scare mongering, those involved should be asked to sit down for tea and biscuits and to explain. I am guessing however, that the were probably not trained.

[MTOW]

I am guessing however, that the were probably not trainedMy thoughts exactly when I first heard about this.

If true, it more or less backs up Wiley's comments about "cheapest option". There was a time, before the beancounters took over damn near every facet of our jobs, where an untrained person would never have been in a position airside or in a maintenance hangar where he or she could have made such a decision (to switch the fittings).

[Going Boeing]

Normally, you would only have to add around 100-300PSI to the system. Off the top of my head, 1850PSI is the aprox. system pressure. 300PSI represents 16% of the total pressure.
The air we breathe is aprox. 78% nitrogen and 21% oxygen. In order for a potentially fatal level of nitrogen to be added, the aircrafts system pressure would have to have been considerably less than 380PSI!!!!!!!!!!

This would be correct at sea level, but, at high altitude a much higher percentage of Oxy is required. If an explosive decompression happened at 40,000 feet, the regulator on each flight crews Oxy mask would give 100% Oxy in order the get sufficient partial pressure of Oxy into each pilot's lungs. If some of the gas being inhaled is not Oxy, then it's possible that the partial pressure of Oxy would be insufficient to remain concious. This error could have had very serious consequences if one of the affected aircraft had a decompression at very high altitude.

[sobast]

Hey NAS1801, You raise some very valid points.:ok: You must be a cone head.;).
You say someone in MEL has already filled a landing gear strut with oxy. I find that impossible to believe. Surely as soon as they opened the oxy tap, the fitting at the strut (wet with oil) would heat up, ignite the oil, turn into a flame thrower and destroy the strut/aero!????
Check this story from the United States Fire Administration.. The pressure regulator’s T-handled adjusting screw had become difficult to move. A maintenance employee used a popular hydrocarbon based lubrication spray on the screw’s threads. The lubrication was done without the knowledge of the nursing or respiratory therapy staff who would have likely recognized the danger in applying a hydrocarbon lubricant. The next time the valve on the oxygen cylinder was opened, the heat of compression ignited the residual hydrocarbon contamination inside the regulator. The burning of the residual contamination was sufficient to start the internal parts of the pressure regulator and the brass body on fire. The health care worker who opened the oxygen cylinder was injured by the molten metal and blowtorch like flames.
Colouring the oxy cart green would be an idea. You cannot legally paint the bottles. They have to be black = international standards.
Magoo31 says The only possible deficiency may have been in the implementation and training stage in Mel, but that is purely speculation.

Hmmm? Maybe look at who did the training at all the ports.
You also say Extensive consultation was carried out across the network with involvement of both trades.

One has to ask "was there enough consultation". Possibly not! Sounds a bit like the ACS procedure for charging the small oxy bottles at the nitro cart. When they did their consultation, there was one BMS cone head oh&s guy on the team. As soon as he questioned their ideas, he got left out of the whole project. They didn't even talk to the oxy cave guys about the issues. Big mistake. Any cone head will tell you that procedure is a croc.

[Managers Perspective]

A similar error led to an engineer being supplied nitrogen during confined space work in a fuel tank at Ansett's Perth hangar some years ago.

On that occasion a (grey) nitrogen bottle was connected to the confined space breathing kit instead of a (grey) compressed air cylinder. Perth used the large compressed air bottles as their air compressor did not supply air of suitable quality for filtering to breathing standard.

Luckily, the engineer was up on a stand and only up in the tank to his waist.

When he became unconscious he fell limp to the hangar floor and was revived.

So, it can happen......

MP.

[NAS1801]

....and one of the findings of the subsequent investigation was that the fittings on the breathing air cart and the nitrogen cart were the same

saw that video some months back.

[Managers Perspective]

Correct, and not just the fittings, the neck of the bottles and thread sizes were the same on both the Nitrogen and the Compressed Air bottles.

And for the record, if he had been working alone he would be dead!

No radio or phone could have helped him.

MP.

[Short_Circuit]

The guys that did the risk assessment on the new carts aren’t the A380 boys by chance? :ugh: O.M.G. :eek:

[sobast]

The guys that did the risk assessment on the new carts aren’t the A380 boys by chance?
Definitely not. One of the team that carried out the RA has been considered a loud mouth bully. Word is he kicked guys off the team when they disagreed with the way things were going. Isn't that right SK?

[whatdouknow]

This just gets better, so the bottles are different colours are the carts not white and red respectively too?

So these were engineers and not baggage handlers doing push backs... :ugh::ugh::=

[the shaman]

I hate to say it, but it could have just been a monumental brain explosion.
18th December 2007 01:09
Maybe a new Queens birthday honour award for LAME's that Fuc,k up .....:D:D give them a ' MBE ' (Monumental Brain Explosion)

[the shaman]

BTW..... I am taking nominations...... bag chuckers may apply

[guidohatzis]

Nitrogen asphyxiation was once used as a means of capitol punishment... I think I see what Qantas is trying to pull here...

[Capt Wally]

...very clever "guidohatzis":)

Yr right QF hardly need to do that to their staff, T&C's are more 'lethal' & the result is ongoing !

Can't believe the stuff up there but it's bound to happen in an ever changing climate where cost cutting etc. is injected into some of the upper management to produce a GM (not General Manager, Genetically modified) been counter !! !:bored:

CW

[Capt Wally]

.....whoooops "bean" counter, must be O2 deprivation & I haven't even been near a QF flight !:bored:

CW

[Excalibur,]

The carts were designed by LAME's, for LAME's and IAW the relevant standards, i.e. colour coding etc.
Extensive consultation was carried out across the network with involvement of both trades.
No they weren't the cheapest or easiest option. They took a hell of a lot of frigging around to get right




My question why did QE design a cart that could be purchased off the shelf and in use with ever other operator,does any one know why?.

[SeldomFixit]

Because, Excalibur, there is the QANTAS way ( applicable to anything at all aviation related ) and then there is the way the rest of the world does it :ok:

[Short_Circuit]

You don't build up you own empire buying off the shelf.

[the shaman]

best suggestion yet is to paint oxy carts green and make this standard colour for oxy servicing GSE.

Also why were the nitro carts not designed to be refillable from a booster & bulk storage bottle bank. This worked brilliantly in my days at Ansett, it saved time and eliminated manual handling of heavy cylinders. Particularly useful at main base where there is a high use of nitro. :confused:

[Deck Zone]

The Shaman

Some Ports are using the old Ansett gear to do just as you suggested.:)

[Excalibur,]

What aviation GSE company built the rigs, does any one know? Surely they have some responsibility.

[the shaman]

maybe magoo 31 can shed some light on this one...???:ugh:

[the shaman]

BTW thanks DZ for info... glad to see common sense and practical use of GSE prevails at some ports..:D:D:D

[wasastudentpilot]

:eek: := Why is everyone looking at the cylinder colour?!?!?! :ugh:

It seems it is actually the colour of the neck (near the valve) of the cylinder that signifies the contents and is therefore what one should be looking at.
The cylinder colours themselves may vary.
For nitrogen the neck is black. For oxygen it is white.
So even "at night, when raining, in blinding sun, under time constraints with a good level of fatigue etc, etc, etc" it should still be fairly obvious if it is black or white on top. You can't get any more contrasting colours than that.
In addition of course every cylinder must also be clearly labelled with the name of the gas it contains.

http://www.bcga.co.uk/preview/publications/tis06-2005.pdf

[sobast]

Hi wasa...
They're actually looking at the colour of the carts that carry the bottles. The necks of the bottles are covered by the enclosed part of the trolley so the neck colour can't normaly be seen.
Part of the problem now is that they've got the wrong people leading the charge to address the issue. How many months have they had to address that and the other issues? Way too many!

[ElPerro]

Is the gas label on the bottles visible when the bottles are on the cart? If so, would someone not notice "Oxygen" is not spelt N-i-t-r-o-g-e-n?

It's a valid point. Do we really need to employ LAME's simply on the basis that presumably they are the only ground handling employee's that can read / understand the requirement to put oxygen where oxygen is required?

[blackd]

I wish the oxy bottle/decompression had occured closer to 1 April. How's this for a headline:

Oxy bottle topped off with nitrogen! Explosive gas mixture error key to 747 mid-air near disaster!

I wonder how long it would take 'em to work it out. :hmm:

[T28D]

Given OXY bottle is black and Nitrogen Grey the labels only confirm contents

[Lagrange Mechanic]

Does the same labling (visibility) efficacy apply for contract disclosure on 'cheap as chips' mobile phone contracts :E :p

[T28D]

Absolutely

[the shaman]

[QUOTE][/ampclamp oxy carts

--------------------------------------------------------------------------------
How long are the "new' oxy carts going to be left gathering dust in a hangar in SYD? QUOTE]

OMFG .... do not tell me these carts are still sitting idle in 131 doing FA... what a fantastic rate of return on shareholders investements... ?????:ugh:

[Ngineer]

Although tech services have ckd crew bottles for oxygen purity, they have not ckd the passenger bottles. Even on the aircraft in question. Their excuse? The pass oxy sys was approx 1800psi when charging so no nitrogen would have entered any bottles. Too bloody difficult would be a more likely story.