Hi All,

I am wondering what are the most suitable gloves to be worn when handling THF?
I have heard that some gloves can disintegrate when in contact with the chemical.
I have read contradicting reports from various sources that some gloves are more suitable than others.

Also, is it an option to double glove? i.e. Wear two pairs of gloves to increase protection.

We currently use either powder free nitrile gloves or powder free vinyl gloves.

Any advice would be greatly appreciated.

FF.

You should first & foremost look at the permeability/compability data of the glove supplier. The reputable ones will have the data e.g There is data for the Ansell Touch & Tuff disposable nitrile glove and they are NOT suitable! From the Ansell range, only their "Barrier" gloves have the reasonable permeation time. Please note that the permation values are from standard tests and may not be the same, i.e. will be less depending upon how the glovves are used.

http://industrialcatalog...emicalagentstid?tid=2375


http://industrialcatalogue.ansell.eu/barrier



The website Jane refered to identifed "4-H / Silver Shield" that are "laminated gloves"

Glove manufacturers generally provide glove selection charts to help you select the correct type. Some are more helpful than others and may have the information you need on their website or by tel call to a technical support team. Be aware that one manufacturer may specify one type of glove( eg nitrile) and another will say that type is not recommended.

The MSDS of the chemical may advise a particular glove (with a disclaimer that you have to check yourself that it is suitable).

Factors to consider as well as Breakthrough/ Permeation time, (time taken for the chemical molecule to pass through the glove) are:
• Degradation rate, (speed with which the integrity of the glove is broken down by the chemical) and mechanical integrity. A glove with 8 hours breakthrough time and excellent chemical degradation is not much good if it is easily punctured or ripped when in use.
• How is the solvent handled? Is the glove for protection against a possible spillage during a short duration task, or will the glove be in contact with the solvent for an extended period? If the former then a disposable glove may be sufficient. Otherwise a combination of gloves may be needed. Eg. a thin inner barrier glove for the chemical protection with an outer glove for mechanical protection/grip etc.

Double gloving (if you mean two of the same type) may not be such a good idea as the now four layers of material between the fingers can make handling difficult and painful. (Fingers get splayed out and its harder to grip)

For Tetrahydrofuran,
Ansell identify a laminated film glove as suitable (8 hr breakthrough and excellent degradation qualities), and a butyl rubber glove with 13 min breakthrough time and fair degradation rate which can be used “under careful control”.
See http://www.ansellpro.com...micalResistanceGuide.pdf

They also say a PVA glove is suitable see http://www.anselleurope....rial/index.cfm?chemical=!ASTM!313!0&lang=EN

Marigold offer 6 or 7 for THF, but if you specify a breakthrough time of >30 min then they have none to offer. See http://www.marigoldindus..._langue_id=386&langu

Hope this helps

Be very, very cautious about assuming that the permeation breakthrough times in the manufacturers' documentation is what you will get in practice. Even EN374-3 tries to make it clear that this is not the case.

The permeation breakthrough test is done according to EN374-3, which test gloves underlaboratory conditions and at room temperature, defined as 22 deg C =/- 1 deg. When a glove is donned the glove will tend to adapt to the temperature of the wearer's skin, i.e. up to 35 deg C. This can have a very significant effect on permeation breakthrough time. For example, one glove, tested at 22 deg C with Dipentene had a permeation breakthrough time of >480 mins. Tested at 35 deg C this had changed to 36 mins, i.e. only 7.55 of the data that would have appeared in the catalogue. The same glove tested against MEK showed a permeation breakthrough time of 1440 at 22 deg C and >240 at 35 deg. C.

Mixtures also play a significant role. For example a glove that showed a permeation rate of >240 mins for each of toluene and MEK tested alone, when tested against a 50:50 mixture of these showed a permeation breakthrough time of just 9 mins!

As has already been stated, degradation can play a major role. So can other factors, such as abrasion, stretching, flexing, ageing (gloves generally have only a limited shelf life). In a study I did together with Sunderland University testing gloves under actual working conditions we found that the data we obtained bore little resemblance to manufacturers' published times.

In fact, according to the data I have, no glove provides more than splash protection against this chemical, not even Viton.

If you wish to be certain about the level of protection you are providing, then there are ways of testing gloves under actual working conditions.

If you need more information on this feel free to contact me off the forum.

Chris

Just as a matter of interest (and my enlightenment), what are people using this substance for?
Clearly, it is widely used for something?