What certificate have or can get to know if a material is good?

There are international standards that set a number of conditions to determine if the shielding material complies with the safety standards required. Therefore, these ballistic standards determine the characteristics of the projectile that will impact the material, the distance, the angle of impact and the number of impacts that will receive a specimen or a sample of ballistic material.

It is important to know that it is different material to stop the vehicle is duly protected. Since a rule determines that the material stopped when done in a laboratory for ballistics tests to a test tube of 30 cm by 30 cm or 50cms by 50 cm., depending on the level and standard. Therefore, you are not specifying if a vehicle has well armoured doors, joints and areas where you could enter a projectile.