Tuesday, 22 June 2010

Safety Gloves for Mechanical and other Hazards

In a previous article we gave details of Safety Gloves for protecting against the risk of handling chemical and biological hazards, now we will give information on other types of safety gloves to protect against other hazards.

Safety Gloves should be issued and worn after undertaking a Risk Assessment for people who have to handle or come into contact with:
  • Materials with sharp or rough edges
  • Very hot or very cold materials
  • Fire
  • Electrical current
There are certain standards that have to be conformed to:
  • EN 388 is for gloves designed to provide protection against mechanical risks. It specifies requirements for resistance to damage from abrasion, perforation, tearing and cutting.
  • EN 407 is for gloves designed to provide protection against thermal hazards e.g. heat and or fire.
  • EN 511 is for gloves designed to protect from cold conditions.
  • EN 12477 is for gloves designed to give protection when using welding equipment.
Gloves for protection against mechanical hazards usually have a fabric base to provide resistance to damage. For years the outer fabric was leather but now the outer is made from a polymer that gives protection from water and chemicals. For resistance to cuts the outer is often made of synthetic high performance yarns e.g. Kevlar™. Generally these gloves are re-usable rather than disposable. However if the outer surface has been damaged they must be disposed of immediately, regular checks must therefore be made.

The types of materials most commonly in use are:
  • Latex natural rubber is a very elastic and flexible material depending on the formulation of a particular glove, natural rubber can offer abrasion, tear and cut resistance. However some people suffer allergic reactions to latex, so individual user requirements must be taken into account.
  • Nitrile gives excellent abrasion and puncture resistance whilst retaining flexibility and comfort. It is also less likely to cause allergic reactions.
  • Polyvinyl Chloride PVC can offer abrasion and puncture resistance, if thick enough it can afford some cut protection. Generally tear resistance is poor.
  • Leather a natural material can be modified during the tanning process to give different properties. Leather gloves come in a large range of thickness and styles and vary widely in protection given, from specialised to very basic general purpose gloves.
  • Kevlar™ brand fibre (Par Aramid fibre) a specialist artificial yarn from which gloves and sleeves can be knitted. These have excellent tear, abrasion and cut resistance.
For gloves tested against EN388 there should be a pictogram with numbers underneath to show the level of protection against from left to right; abrasion, cut, tear and puncture. The levels go between 0 and 4 for abrasion, tear and puncture and 0 and 5 for blade cut resistance. 0 means it has either not been tested or has failed.

4 2 3 1

There is also a pictogram for gloves that have a particular resistance to impact cuts

At no time should protective gloves be used as an alternative to the fitting and proper use of guards on machinery or tools.

Thermal Hazards

Gloves that are resistant to thermal hazards either heat or cold can be manufactured using a variety of materials.
  • Aluminised gloves help with the reflection of heat and are normally used where the main source of heat is radiant e.g. in a blast furnace. Materials often aluminised are Para Amid and leather.
  • Leather is a good protective material against cold as long as it does not get wet and often they are treated with waterproofing agents. Leather is also a good material for welding gloves as it does not melt or burn unlike many synthetic fibres.
  • Poly Viloft is a synthetic fibre that gives good thermal insulation properties against cold.
  • Para Aramid e.g. Kevlar™ developed for aerospace to give heat resistance for the extreme temperatures during re-entry into the Earth’s atmosphere, is extremely good against flame, and convection heat.
  • Cotton has only moderate resistance to heat and cold, the main problem is that to be effective the material has to be thick which limits dexterity.
In the standards for resistance to cold the following categories are used:
a. Resistance to convective cold 0 to 4
b. Resistance to contact cold 0 to 4
c. Permeability to water 0 to 1

The Pictogram used to show that gloves are resistant to cold is

3 2 1

In the standards for resistance to heat the following categories are used:
a. Resistance to flammability 0 to 4
b. Resistance to contact heat 0 to 4
c. Resistance to convection heat 0 to 3
d. Resistance to radiant heat 0 to 4
e. Resistance to small pieces of molten metal 0 to 4
f. Resistance to large splashes of molten metal

The pictogram used to show the gloves resistance to heat is

4 3 2 3 2 1

There also standards applicable particularly to chainsaw protective gloves that have been covered in previous articles on the Granite Workwear web site see A Guide to Chainsaw Protective Clothing and Equipment published 11th June 2010.

In our range of gloves we have products that cover all aspects of protection.

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