Slash resistant clothing can reduce the risk of knife injuries and laceration.
by Robert Kaiser
People throughout history have sought and found the means to protect themselves with specially designed and constructed garments. From furs and chainmail, to leather, metals or fabric, a range of materials has been used creatively to protect against injury or even death.
With the evolution of specially engineered fabrics, the wearer is offered a higher level of both protection and dexterity, as well as protection against very specific threats. Although cut-resistant fabrics have been on the market for some time, these materials were not as effective against slashing.
People tend to believe that most knife crime victims have been stabbed, but in truth, the majority will have been slashed. Ian Horsfall and Mathew Arnold of the Impact and Armour Group within the Department of Engineering and Applied Science at Cranfield University (Defence Academy of the United Kingdom) wrote a comprehensive piece on “Protecting From Slash Knife Attacks.” They report, “A retrospective survey of hospital admissions data that contributed to the development of the standard suggested that 63 percent of wounds attributable to sharp edged weapons were slash events.”
Responding to the danger
Slashing has become a regular occupational hazard for many public-facing professionals. The key function of slash-resistant clothing is to effectively reduce the risk of lacerations and protect key arteries. Attacks may be perpetrated by highly trained individuals who purposefully attack a vulnerable area to incapacitate a police officer; others may accidentally slash limbs in a frenzied attack. The objective is that slash-resistant clothing prevents such injury and keeps the wearer of protective clothing fully operational, unharmed—and alive.
Slash resistant clothing has been developed to significantly improve personal safety by offering high levels of cut protection to areas where commonly used body armour and other types of personal protective equipment (PPE) leave the body exposed and vulnerable.
Cut-Tex® PRO by U.K.-based PPSS Group is a soft, machine washable and comfortable, single-knit fabric designed for cut and slash protection. Working with such fabric is a challenge. At the beginning and early stages of the project to develop it, different fabric cutting technologies were tested, ranging from circular and straight cutting machines, to CNC and water jet cutters. Ultimately, the company chose circular (round) cutting machine.
The material has been tested at a U.K. based ISO 9001:2008 quality standard accredited manufacturing facility in England. Originally engineered to produce cut-resistant workwear for flat glass and sheet metal processing facilities, the fabric was extensively field tested in additional environments and is now used across a range of sectors.
Focus on specific areas
Researching and developing slash-resistant protective clothing has required an understanding of human anatomy to protect arteries and major blood vessels. This was done by focusing on specific areas:
- The side of the neck and throat.This area contains the carotid artery and jugular vein. If either is cut the victim will bleed to death rapidly. A horizontal cut across the neck will also cut the trachea and ligaments that control movement of the head. Slash resistant neck guards, balaclava or high-neck, upper body garments made from Cut-Tex® PRO will make such injuries extremely unlikely. One could argue that such risk could be eliminated.
- The arms.A deep enough slash to the inside of the forearm between the radius and ulna bones will sever the radial artery. Severing the radial artery can result in unconsciousness in 30 seconds and death in as little as two minutes. The brachial artery is deep, but severing it will result in unconsciousness in as little as 15 seconds and death in as little as 90 seconds. Tendons pass through our wrist and are attached to our fingers. If an attacker were to cut those tendons or muscles that power them, the officer’s hands will no longer be able to close or to hold anything.
- The legs. Besides the femoral artery, there is an extremely vulnerable area just above the knee, as the muscles in the legs narrow and connect to the patellar tendon. As a large surface area, an attacker who is close would be close enough to reach the quadriceps, making the victim unable to defend him or herself. Slash resistant “long johns” are designed to protect the entire leg from lacerations, keeping the wearer mobile.
Beyond a personal attack, there are other scenarios that pose dangers. When officers enter a building, they may have to maneuver over broken glass and either climb over or swing through window or door frames. If the vulnerable areas of the body are not protected, severing an artery is a serious risk.
In March 2019, the U.K. edition of The Guardianfeatured the headline “Police shoot man after officer slashed with knife.” Unfortunately, this was hardly an isolated tragic incident. More recently a global headline read, “Japan knife attack kills 2, injures 16 others at bus stop.” Emergency services and first responders were at risk when engaging with this situation.
Technical Lead for PPSS Group, retired counter terrorist police officer Colin Mackinnon, can support the statistics with personal experience. “I have been the victim of a knife attack,” Mackinnon says. “The offender who had martial arts training attacked me with a concealed knife. Even with training, in the heat of the moment they used a slashing motion rather than a stabbing motion, resulting in four deep cuts to the front of my stab vest before they were overpowered.”
The future of slash resistant clothing
Many technical textile engineers and yarn producers globally are working to further improve cut resistant fabric. The common goal is to make slash resistant clothing, and PPE in general, lighter, thinner and more breathable. The journey to do so starts with raw fibres.
Future yarns will offer us a greater weight/performance ratio and allow us to produce protective garments that look like any other garment. Right now, too many frontline professionals, such as counter terror officers and covert intelligence and surveillance officers choose to not wear currently issued PPE because they think it’s too hot and too cumbersome. Additionally, there is risk that if anyone would recognize the garment as PPE, their lives could be at risk.
Clothing, uniform, workwear and tactical apparel producers have recently started to analyse the performance of yarns and fibres previously only available to the military and aerospace, all with the safety of frontline professionals in mind.
Robert Kaiser is the CEO of U.K.-based PPSS Group, a producer of high performance PPE. He is also a consultant for several international governments and has articles in industry publications in several countries.