The dye blend selected for use in DyeWITNESS™ was to conform to the primary purpose of the product - safe self defence. These dyes are approved for use in foods, drugs and cosmetics. These are safe for human use and are used extensively everyday in numerous applications. The dyes included in the water based DyeWITNESS™ cannot hurt or harm any individual if the spray enters ones eyes, touches the skin, is inhaled or swallowed. Far superior staining dyes are available on the market, but they were not used as they were considered risky in terms of human safety, contrary to the DyeWITNESS™'s objective.

When different fabrics are dipped together into a bowl containing dye and water for twenty minutes and then removed, the results will vary. Each fabric will absorb different amounts of dye and the resultant shades will vary when dry. This is because each fabric has its own unique texture, structure and absorption capability. Human facial skin behaves in the same way. Porosity, oiliness of the skin and pigments are different in each human being.

In an attack situation there are many variables that could influence the degree and the lasting effect of staining of the attacker's face. The distance the spray travels, the volume of spray that is deposited on the face, the angle of contact, the length of time the spray stays on the face prior to wash off, prevailing wind conditions etc, all of which are unpredictable in any attack. These factors in addition to the ones related to the skin explained in the previous paragraph, have a direct impact on the degree of staining and how long it will last. These are variable and uncontrollable. So the results of staining will consequently vary as well.

In most cases the attacks occur in an area 20-30 minutes or more of travelling time, away from the home of the attacker. These statistics have been obtained from well-known Crime Prevention Authorities and are applicable to many countries. After the attackers face is sprayed, he takes 10-15 seconds to partially wipe the foam from his eyes with his hands, as he tries to flee the scene of the crime. He will leave distinct fingerprints on anything he touches on his way home. Due to the horrendous look of a sprayed person, it is unlikely that he will attempt to wash off in a public washroom. The balance of the foam remains on his face until he washes off at home. In this time period of 20-30 minutes until he washes off, the color of the dye gently enters the skin via the pores. This color can stay on his skin up to 8 days to assist identification. His clothes will be permanently marked. If someone washes off immediately, it is unlikely there will be a lasting stain on the face. However we know that attackers do not run around with a bucket of water and soap during an attack. It is important to understand the basis of staining with DyeWITNESS™ to fully appreciate this safe, effective and intelligent product.

It is also important to note that the texture of facial skin is quite different to skin on ones hands, feet, body, etc. This means that facial skin will respond to staining uniquely. For instance it would be incorrect to spray ones hands and wash it off quickly as a method of evaluating staining capability. In a real situation, the attacker becomes excited / anxious prior to and during the attack. His blood pressure and pulse increase, enlarging the pore size on his skin. This makes the skin more receptive to the dye and improves its absorption capability. It is the face that gets sprayed under pressure and the foam remains on the skin for up to 30 minutes, prior to wash off. Testing it any other way would not be representative of a real situation.

Immobilises - more effective then pepper spray or mace (which are illegal)

Foaming Dye  - stains green for up to one week for easy identification

Sprays - three times the distance of mace or pepper spray (which are illegal)

On Impact

4 Seconds

7 Seconds