What is Knife Retention equipment?:

Knife Retention products primarily provide resistance to edged threats through retention based mitigation. They also have the capability to retain forensic material, for later retrieval. The plates furthermore can protect against damage to underlying armour from knives, mitigating expensive replacement. Plates can also be certified to Home Office Blunt Trauma protector standards, should you require this.

Can they be convex, custom sizes, or handheld shields?

Yes. You’ll get the same quality, and Knife Retention capability. You can also choose different cuts, such as SAPI cut. For shields, you should check door sizes before ordering, if they are non standard. We can provide smaller shields to ensure they fit through these widths.
 

How does Knife Retention work?

Retention of a knife can be achieved thanks to a unique blend of smart materials, which have just the right ratios, stereochemistry, post production treatment and more to ensure that a knife can become retained. As the knife passes through, it decelerates and the equipment can absorb / dissipate energy from the strike. Once it's in, it is extremely difficult to be pulled out again via the same angle of entry. You can, however, retrieve the knife when you get to safety. A guide for doing this safely is provided below. Once a knife is retained, you can deal with the assailant, get to safety, or get help. It's designed to buy time, and level the playing field. All of this can happen without any skill, or awareness of the threat.

Why doesn’t it always retain everything?

The retention feature is proportional to the threat the equipment is presented with. The sharper, more knife like an object is, and the greater the force applied, (the more intentional and the more chance of harm there is) the more likely it is to become retained. The motion and angle of the knife before it strikes is also a factor, whereby near vertical upward or downward strikes (slashing) by a sharp weapon may mean that it is more likely to move across than become retained. This is the same as with any traditional ballistic plates. Intentional stabs with a sharp weapon at an angle perpendicular, or similar, to the strike face increases the chances of retention. This means the plates should not be compromised by unintentional damage, such as bumping into every day objects, but are designed to offer protection from intentional, or potentially life threatening action.

Why is there a circular hole at the edge of the plate? Is this deliberate?

This is known as the air pressure regulation vent. It is designed to prevent expansion or damage in situations where the plate is exposed to air pressure changes, such as those experienced at high altitudes, or those caused by temperature fluctuations. It further doubles up as a drainage point if liquids become captured, such as those ejected by tranquilliser darts, or similar remnants of payload delivery weapons, It is essential for the vent to remain clean and unobstructed at all times. You can also perform internal cleaning via this vent.

How do I clean the plates?:

For external cleaning, wipe with a cold damp cloth. Plates that have been certified to “wet testing” can be immersed for cleaning internally. This is where, after immersion in water at 20°C, they are then tested to the same Blunt Trauma standard. This means plates are not affected in their blunt trauma effectiveness by water at this temperature for this time frame. You can also clean out the inside of the plate, by placing it in cool or room temperature water, letting the water enter the pressure regulation vent, shaking the water around to ensure it reaches all areas, and then draining via the same point of water entry. Repeat as necessary.

Why must the equipment be kept below 50°C at all times?

For equipment that have been certified to HOSDB (20/07) testing standards, these will have been subjected to at least 2 hours of heat at 50°C, followed by a blunt trauma strike. This means that these have only been certified and tested to this temperature. We therefore, cannot claim operational protection or effectiveness past this point. If 50°C is exceeded, even briefly, including on Knife Retention equipment not certified to HOSDB 20/07 Blunt Trauma standards, it is possible that the equipment will not continue to work as intended, and this may invalidate any warranty. You can keep these cool by always keeping them in carrier vests, not exposing them to direct sunlight on warm days, and never leaving them in vehicles without active cooling on warm days.

How do I remove a retained weapon, or discharge thereof?

The force to remove a weapon is potentially significantly greater than the energy exerted at inserting the weapon. Once you are away from the threat of attack, place the plate or shield down on a hard surface, with the weapon perpendicular to yourself and others nearby, then, with correct PPE worn, take a blunt object such as a hammer, and nudge the weapon gently back and forth along the angle of entry. Similar to pulling a lever side to side repeatedly. This gradually makes the hole bigger, and eventually, will cause the knife to loosen, and fall out. This process can take several seconds, to several minutes, depending on how deep the weapon has penetrated the plate, and the nature of the weapon itself. It may also depend on the blunt object you're using. An assailant is unlikely to have the time, nor ability, to retrieve their weapon once you have reacted to the strike, and retained the weapon. Only authorised professionals with correct PPE should perform this. You should not attempt this yourself. Sharp objects can cause serious injury, or fatality.

What about forensic material?

For forensic retrieval of liquids or powders captured in the equipment, you can extract them via the pressure regulation vent on the side if it is safe to do so. You should not attempt this yourself. Biohazard or chemical attack residue can be life threatening, and retrieval of such materials should only be done by qualified professionals, with suitable equipment, authorisation, and experience. Retrieval after exposure to such an attack is extremely dangerous, and may result in serious injury or fatality.

NEVER attempt to remove sharp objects stuck in the plate by hand. Always use a blunt object such as a hammer to give yourself space between you and the weapon when removing it. Attempting to remove retained objects by hand may result in serious injury.

NEVER attempt to pull the weapon out at the same angle of entry. Efforts to do this can be futile, or dangerous. The force at which you need to pull the weapon out in this way, can be greater than the insertion force. Sudden dislodging at an accelerated rate can be dangerous.

NEVER reuse plates that have been struck. Whilst these plates can potentially offer continued retention capabilities after a single strike during a multi assailant attack as a "worst case scenario" potential benefit, they may not offer the same blunt trauma protection, nor can Knife Retention / blunt trauma capability be guaranteed. Therefore, you should never reuse a struck, damaged, or otherwise compromised piece of Knife Retention equipment. If in doubt, or you believe the equipment has been struck, even once, you should always replace this. In many circumstances, we can still recycle the plate free of charge.

ALWAYS wear the correct PPE.

*Whilst primarily a blunt trauma protector, knife retention is a feature of its proprietary design and construction, demonstrated during in-house testing. However, as with any impact mitigating system, actual retention outcomes may vary depending on strike angle, weapon type, and applied force.