Rank: New forum user 
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I have recently joined a company where their SSOW for transferring cryogenics states that ‘cryogenic gloves should be worn if there is any danger of touching cold metal; these should be loose fitting so that you can remove them easily. If you are transferring small quantities of liquid nitrogen and there is no danger of touching cold metal then it is usually safer not to wear gloves’.
In my previous experience of working with liquid nitrogen in cell biology labs, cryogenic gloves were always a requirement for anyone transferring cryogenics or transporting even small dewars of cryogenics.
Any thoughts on this would be appreciated.
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Rank: Forum user 
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Similiar experience to your own when I use to deal with labs with biological samples.
I think the risk re. the statement on the SSOW you have provided is that the proposition of doubt:
- "there should be no" infers that they could be; and
- "usually safe" infers that it may not be.
I understand the management of risk but this reads less like a SSOW and more a bit more like some vague recommendations. May be worth using some examles like - http://www.safety.ncl.ac...%20Liquid%20Nitrogen.pdf and http://www3.imperial.ac....tallive/docs/1/41628.PDF
BS5429 should also provide you with something of what you need.
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Rank: Super forum user
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My view is it depends on a lot of factors. The quantity and the activity being undertaken being two. I note that the Imperial risk assessment linked in the previous post gives examples where cryogenic gloves and a face shield are not used.
Decanting and transferring nitrogen are not precise phrases and they may cover a few ml up to hundreds of litres. Likewise dewars range from 1 litre to hundreds of litres.
We need more information about what they are doing before giving opinions.
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Rank: Super forum user 
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You need to consider the requirements of the lab work.
If a few mls of LN2 or some chips of cardice suitable gloves should be used to transfer these from stock to a smaller transfer container. That might be a wide mouth thermos or polystyrene bucket/domestic-style ice bucket from which the need for gloves may not be cryogenic but for something providing chemical of biological protection, to protect the worker and/or the work from exposure/contamination.
Indeed, if there is a risk of contamination then cryogenic gloves should not be used since these would have to be managed after use, ie, as potentially contaminated waste!
Key is to consider how to transfer using a small safe, easy to use and perhaps disposable transfer vessel, and if necessary to protect the work as well as the worker. Keep volumes as low as possible and top up when required rather than too large a volume to begin with
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Rank: New forum user
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Many thanks for your replies.
Our processes do range from smaller quantities (~2 litres) up to much larger vessels. When the larger vessels are used then PPE is worn. However, when the smaller dewars are being used and transported around site the operatives are not wearing PPE. In these circumstances the advice that is given is as follows; ‘in the event of liquid nitrogen being splashed onto your bare hands accidentally, spread your fingers as you move your hand away. This will help to prevent cryogenic burns caused by droplets of the liquid being trapped between your fingers’. My belief is that if there is a perceived risk then PPE should be worn. The response I am receiving (from Managers) is that the operatives are very experienced and have worked with cryogenics and the risk of a splash is minimal and in any event a splash to the skin will not result in a burn if the liquid is allowed to run off the skin.
My original post may have been confusing. The environment I am referring to is a production facility and there are no issues with contamination.
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Rank: Super forum user
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Bear in mind that cryogen gloves reduce your dexterity to the level of a chimpanzee in boxing gloves. I have some sympathy for your managers.
Back in the 60s we used to handle cryogens without gloves, in much the same way that you don't don anything special to pour boiling water from a kettle. Note that boiling water in this example is more dangerous than liquid nitrogen, as if you pour it on your skin you will be scalded.
I did get the odd chilblain, but never a cryogen burn. The containers were designed so that the handles, and casings never got cold enough to deliver a burn, so the risk was minuscule. I cannot recall ever spilling any directly on any part of the body.
If I were filling dewars from a tank, however, I would want gloves and a face shield, as splashes are common and the pipework gets extremely cold, as do the valves.
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Rank: New forum user
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I like your boiling kettle analogy Jane! I guess what you are recommending does tie in with the SSOW in operation here. Thanks again for your feedback.
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