As an Aerospace depth maintenance organisation we often send working parties overseas & to mainland Europe. One such working party is currently in Belgium & has a requirement to carry out a process involving Liquid Nitrogen, unfortunately we have been unable thus far to source a supplier in their local so it appears our only option is to transport a small quantity in a 3Ltr flask with a screw & clip top via Euro tunnel by car. Question ~ other than ensuring the flask is secured upright & has the relevant MSDS, COSHH Ass & Risk Ass for its use, what other (if any) documentation needs to be carried, what warning signs need to be displayed on the vehicle & are there any EU Laws / Regs that would prevent us from doing this?

The working party would be dead by asphyxiation beforew they left blighty. 3 litres liquid Nitrogen will result in 2049 litres of gaseous nitrogen. Under the Carriage Regulations, liquid nitrogen must only be transported in vessels which are suitable for this purpose. Ordinary vacuum flasks (‘thermos’ flasks) are not suitable. 3 litres of liquid nitrogen will become 2049 litres of gaseous nitrogen. Also as liquid nitrogen is cold, it will condense any moisture in the atmosphere, with the possibility of forming a water-ice plug which may seal the dewar vent, causing the pressure to build up. This can result in an explosion hazard. NITROGEN, REFRIGERATED LIQUID Product UN number, ie UN 1977 Product danger sign, ie a green diamond with a cylinder symbol and the number 2 at the bottom Dewars must be transported separately from the driver or passengers. Flat-back vehicles, vehicles with a separating bulkhead that gas cannot leak through or trailers should be considered. Dewars shall not be transported in cars. The driver shall carry a document with the following information: product UN number, ie UN 1977 product designation, ie NITROGEN, REFRIGERATED LIQUID product classification code, ie Class 2.2 the volume of each dewar and the number of dewars the consignor’s name and address the address of the consignee (if known) In the case of transporting 3 litres no driver vocational qualification is required Refer to BCGA CP 30 Rev 1 And DO NOT TRANSPORT BY CAR

* however required.

For anyone interested the 2009 ADR is freely available online http://www.unece.org/tra...adr2009/09ContentsE.html

Interestingly, provided that the receptical is double walled, vacuum insulated surrounded by absorbent insulating material protected by an iron basket and placed within a metal case with carrying handles then the provisions of ADR do not apply. (Special provision 593) Most importantly the container must not be in the same compartment as the driver and passengers (Would suggest a cage chaines or secured to the back of a pick up/open truck. Main content of the brief: What to do in the case of spillage What do do in the case of contact with liquid nitrogen How to recognise signs of ice plugging and emergency action. i.e evacuate area, contact the emergency services (they may have to sand bag the container).

Lets put this in perspective - 3 litres of liquid nitrogen evaporated into a car would kill the occupants, so it is essential that the boil off does not happen within the vehicle and that there is no possibility that it spills into the vehicle. However, evaporated into a larger volume of air, the risk rapidly diminishes. In my office, which is approximately 18 cubic metres, it would only reduce the oxygen concentration to around 18%. This would not be a danger to my life, unless it spilt all at once and I was actually in close proximity to the boiling liquid. Vacuum flasks which are specifically designed for liquid nitrogen and have vented lids, so if this is the vessel referred to then it is safe for the purpose of carrying liquid nitrogen. The domestic vacuum flask is not suitable, because the lid will screw down and then the contents will explode - but this will happen long before you reach the tunnel. I have come across the ice plug problem, but mostly with really old equipment that had very narrow necks.

There are no problems in getting deliveries of LN2 in Belgium or elsewhere in Europe though as always the issue is of scale - few suppliers will be interested in such small volumes but will probably direct you to one of their clients from where you can purge your vessel and collect the small volume that you require. As for Eurotunnel - the calculations are perhaps sufficient to impress some of the readers here but for God's sake don't turn up at the Tunnel and tell them its OK, someone here who hasn't even given their name says its fine! It's their tunnel, and their rules. Ask first and prepare for a refusal. Absorbent material is a fun idea - heaven alone knows what an outer layer of absorbent material would absorb! Spilled LN2 would percollate right through it quickly, and still boil off rapidly. The need for absorbent material is surely to soak up only the frozen liquids that you may be transporting - not the LN2. And for the requirement to keep the dewar out of the passenger compartment and instead in the boot, this is a little more nonsense on which I would not rely. Unless of course your boot is airtight from the passenger compartment but separately and freely vested to the outside. For road travel in cars in the UK only, the general advice is to use the boot (to avoid burns from direct contact), but to keep at least 2 windows at least 1/2 open in the passenger compartment to ensure sufficient ventilation. And if you feel your feet getting cold, get out quickly! Do take care, with the LH2 that you use and the advice that you rely upon.

Do I see bleve describing a bleve above?

Jane I think Ian was just showing off his cyrillic capability. P

Travel by car is repeatedly referenced, and where is the goods compartment....the boot, unless you propose the glove compartment or a roof rack! And how ridiculous to say that Eurotunnel have no grounds to refuse .... it's their tunnel and they can set whatever rules they want, as can the various regulatory bodies to whom they are responsible. I would think a fair bet that they would refuse; trying to bully them into agreement with your own opinion is pointless and entirely inappropriate