2003 – CHEMICAL & MICRO-ORGANISMS
Resistance to Permeation:
Resistance to permeation is assessed by measuring the time for a chemical to break through the glove material. Samples, cut from the palms of the gloves are placed in a permeation cell which enables the chemical to be placed in contact with the outer surface of the glove. Collection air or water is passed through the cell to collect any chemical that has broken through to the inside surface of the glove samples.
The â€˜Chemical resistantâ€™ glove pictogram must be accompanied by a 3-digit code. This code refers to the code letters (A-L) of 3 chemicals (from a list of 12 standard defined chemicals as shown below), for which a breakthrough time of at least 30 minutes has been obtained.
|Code letter||Chemical||CAS number||Category|
|E||Carbon Disulfide||75-15-0||Sulphur Containing Organic Compound|
|H||Tetrahydrofuran||109-99-9||Heterocyclic and Ethereal Compound|
|K||Sodium hydroxide 40%||1310-73-2||Inorganic base|
|L||Sulfuric Acid 96%||7664-93-9||Inorganic Mineral Acid|
Permeation: The process by which a chemical agent migrates through the protective glove at a molecular levelÂ (performance level 0 to 6). Performance levels are assessed according to the breakthrough times of the chemicals.
|Measured breakthrough time||Performance Level||Measured breakthrough time||Performance Level|
|> 10 minutes||Level 1||> 120 minutes||Level 4|
|> 30 minutes||Level 2||> 240 minutes||Level 5|
|> 60 minutes||Level 3||> 480 minutes||Level 6|