What are the risks of nitrogen gas?

Assuming you are NOT talking about liquid nitrogen and that you don't need the generic risks involved with compressed gas cylinders to be repeated here, just about the only thing you need to be concerned about is the asphyxiant effect of nitrogen which may displace the oxygen in an enclosed or poorly ventilated space. Perhaps you could give a bit more detail about exactly how and where it is being used?

http://www.boconline.co....lth/gas_safety/index.asp When looking at cylinder safety I got a lot of useful information from the above site - BOC had a arange of info but it took some finding. I'm running late and so can't help more than that at the moment.

In that case, most of your risk assessment can simply record the hazards that these control measures are managing, record the control measures themselves, and record that, although an asphyxiant, there is no risk of asphyxiation. You also need to look at how the gas bottle gets to its current position, who is authorised to fit the gas regulator, and the periodic checks/replacement regime that is needed for the regulator. However, the use of the gas (pressure testing) is another matter altogether. What are the things you are pressure testing? What is the stored energy? How is it being done?

The testing side is covered in the PED examination so I'm OK with that. I didn't see anything on the hose but to be honest I didn't look close. Its just when I saw it on the BOC site that it sprung to mind. It was contractors (I know, I know!!). I'm going to chase them up, they are off site now.

Asphyxiation from a single cylinder is unlikely in a large room, but if you are concerned why not have a go at a gas calculator: http://www.phy.cam.ac.uk/hands/hazards/oxygen.xls and find out. You only need a tape measure to measure the bottle dimensions, and the record of the fill pressure which should be on the label. All the yellow cells can be altered by you. You should not attempt to alter any other cell. Before you use the results, please read the instructions, which list the simplifying assumptions: http://www.phy.cam.ac.uk/hands/hazards/notes.doc

From HSE(East) press release 08/12/09 'CNH (UK) Ltd fined £70,000 under HASAWA 1974 s2. HSE also prosecuted the firm in a separate case after it admitted another 5 charges relating to workplace transport. It was fined £25,000. CNH (UK) Ltd were ordered to pay combined costs of £58,898. An engineer was nearly suffocated by a nitrogen gas leak in a laboratory. The man only survived because he heard gas escaping and felt cold vapour on his arms. Seeing a mist in the laboratory, he staggered out, feeling light-headed and weak. He was off work for five weeks afterwards with headaches and insomnia' Just for info.