diff --git a/external/lab-hsa/ppe/ppe.md b/external/lab-hsa/ppe/ppe.md
index 5577302f674ec864baabf0b8d735924035eeaf63..441acb28b4f20f29a1e9c8c1293643e58d5aa703 100644
--- a/external/lab-hsa/ppe/ppe.md
+++ b/external/lab-hsa/ppe/ppe.md
@@ -121,7 +121,28 @@ If the gloves are not contaminated, discard them in the domestic waste bin of th
   EN 420: general requirements (identification, size, norms, composition,...)
 
   EN 455 1-4: physical properties
+For activities with hazardous biological agents and harmful chemicals it is strongly recommended to use category III PPE gloves, and not medical exam gloves. 
 
+Quality level and norms are often summarized with the mention Cat III and AQL (acceptance level quality) on the gloves packaging or on the technical datasheet.
+
+<div align="center"> 
+<img src="img/Gloves4.png" width="20%"> 
+</div> 
+
+Disposable gloves of category III involve fulfillment of EN420, EN388, 374-2 and 374-3 requirements. Cat III is the highest protection level. 
+Category III PPE gloves are tested to fulfill requirements of:
+
+- General guidelines (identification, size, norms, composition,...) (according to norm EN420)
+- Mechanical resistance (according to norm EN388)
+- Penetration by chemicals (according to norm EN374-2: 2003)
+- Permeation by chemicals (according to norm EN374-3: 2003)
+- Protection against micro-organisms (according to norm EN374-2: 2003)
+
+Additionally, 2 other references make sense for our specific activities: 
+EN 374-5: micro-organism resistance (bacteria, fungi, viruses)
+EN374-1 type B. Permeation resistance of at least 30 minutes with at least three test chemical(s). 
+
+For activities with hazardous biological agents and harmful chemicals the use of nitrile gloves is recommended.
  #### Safety goggles (highly recommended)
 
 <div align="center">