Tag Archives: Kevlar

Uniform Series: Kevlar, the life-saving textile

23 Aug

During this uniform series, we’ve focused on firefighter and police uniforms. This final post of the series focuses on an amazingly strong and lightweight textile used in both uniforms, Kevlar.

In the mid-60s, Stephanie Kwolek, a chemist working for DuPont, invented Kevlar, opening the doors for polymer chemistry. Kevlar is an extremely strong, flexible, and tremendously flame, heat, and cut-resistant textile with a high tensile strength – five times stronger than steel, and 20 times stronger than steel when underwater. Kevlar’s superior strength lies in its hydrogen bonds that strengthen the monomer (a molecule that chemically binds to other molecules), making it into a strong polymer chain.

Kevlar is used not only in emergency services clothing and equipment, but has uses in industrial, workplace, and military safety, and is present in automotive and sports equipment, rope, and fiber optics. Many people rely on the strength of Kevlar to confidently and effectively do their jobs.

Firefighting and Kevlar

In high temperature situations, Kevlar can withstand temperatures up to 300°C and still retain its strength properties, so it is an ideal material for firefighting uniforms and equipment. Kevlar is virtually indestructible and with the exception of a few powerful acids, solvents are ineffective at damaging Kevlar. Kevlar is slightly susceptible to ultraviolet light.

Toronto firefighters wear heat and flame-resistant Kevlar bunker coats and pants, and carry oxygen tanks wrapped in Kevlar.

Toronto firefighter boots are made of heavy, thick, and waterproof rubber, insulated with felt and heat-resistant Kevlar. Bunker coats and pants of the firefighting uniform are made of Kevlar and Nomex (another DuPont flame-resistant textile) with a water barrier to keep out water and chemicals. The fabric of the outer uniforms are breathable, allowing metabolic heat to escape and reducing heat stress in the body.

“DuPont™ NOMEX® and DuPont™ KEVLAR® brand fibers will not melt, drip, or support combustion, providing a stable barrier that helps minimize burn injuries. The flame resistant properties of NOMEX® and KEVLAR® are permanent; they cannot be washed out or removed in any way. Durable DuPont™ Teflon® HT water-repellent treatments prevent water from compromising valuable air layers that provide the bulk of the garments’ thermal insulation.” (Source.)

Kevlar also in a firefighter’s SCBA, self-contained breathing apparatus. The aluminum oxygen tank is wrapped in Kevlar and strapped to the back, protecting the firefighter from the combustible gas from exploding during fire calls.

For more information about DuPont’s firefighting protective gear, please see this page of their site.

Policing and Kevlar

A thick Kevlar plate rests inside of police bullet-proof vests.

Kevlar’s lightweight ballistic and stab-resistant textile technology is used in police gear and military body armor; it is the bullet-stopping material that makes up bullet-proof vests. When I toured 51 Division in Toronto, I had a look inside of the vest to inspect the Kevlar plate within the vest. It was spongy and firm, and felt like dense foam.

The DuPont site explains Kevlar as “bullet-resistant tactical vests work by “catching” a bullet in a multilayer web of woven fabrics… Whether it’s engaging a fast-moving projectile or helping to stop the blunted bullet, body armor made with Kevlar® fiber helps offer law enforcement officers superior protection in multiple situations.”

Kevlar is such an amazing produce that many police officers owe their lives to this DuPont textile. Their website features videos of survivor stories from police officers who owe their lives to their bullet-proof Kevlar vests.

Kevlar is a major component of emergency services uniforms in Toronto and throughout the world. Kevlar marries science and clothing to form the world’s most cutting-edge protective textile, so people in dangerous jobs can feel safe and confident in their work.

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Uniform series: Toronto Police Services

9 Aug

Toronto Police uniform, 1900.

Part of my training as a costume designer was studying costume history, including some military history. I found uniforms particularly fascinating because of the beautiful lines and cuts, and the brilliant and logical practicality of military gear.

I was privileged to inspect the military-like uniforms of the Toronto  Police Services (TPS) for this series and was first shown the historical police uniform displays set up on the main floor of 51 Division by Community Relations Officer, Constable Peter Cullingford.

The typical police uniform from the early 20th century consisted of a navy wool tunic with a mandarin collar and metal buttons, navy trousers, and a thick leather belt that housed a baton, offering little protection. Luckily for today’s officers, uniforms are designed with safety and ergonomics in mind. I was delighted hear about health and safety committees and a clothing committee for officers, to keep them protected and in good health.

The modern uniform

The military is about order and precision, with neat identical uniforms. TPS shares the military order and police constables receive cleaning vouchers to keep their uniforms clean. Senior officers however, must  handle the cleanings on their own. 51 Division Supervisor, John  Tanouye, impressed me because he cleans and presses his own shirts, and I must say, he does an impeccable job.

Police cadets, constables, sergeants, and staff sergeants wear stiff, twill, navy  polyester/cotton blend shirts, and senior officers wear thinner white shirts. However, during large police operations, senior officers wear  navy shirts so they blend in and don’t stand out.

Police shirts have epaulets, shoulder pieces used for insignia of rank by armed forces and other organizations. On the shirts themselves, the epaulet is made of “self” fabric (shirt fabric), but when worn on a dress uniform, the shoulder insignia – a.k.a “shoulder flashes” attaches to the jacket shoulder, displaying colour-coded symbols of their rank – silver for staff sergeants and below, gold for inspectors or above.

Navy trousers are a soft, poly-cotton fabric blend that wash-and-wear well. The red stripe down the trouser leg signifies an armed, municipal, sworn constable. Under the dark trousers are dark socks for reasons outside of proper gentleman’s dressing, as PC Cullingford explains. “White socks would look silly and at night, they would stick out like a sore thumb reducing a stealthy approach, if seen,” he says, “Dark socks have been in our rules and regulations for decades.”

Forge hat

The forge hat, worn throughout the year, has a mesh band around the crown, allowing breathability during hot weather. In cooler weather, a band of red poly-cotton braid is worn over the mesh to keep the heat in. Of course on really cold days, officers wear the heavy ear-flapped ushanka hat.

Senior officers work in offices and wear clean black lace-up shoes that they polish themselves, but constables in the community wear Canadian-made, waterproof, black ankle boots with thick soles, lined with Thinsulate and Goretex. As PC Cullingford, formerly of the mounted unit, can tell you, waterproof everything is essential when working outdoors – he explained how awful it is to sit on a horse for hours in the pouring rain during parades and protests.

Side opening reveals the zip-out lining.

The three-season, machine-washable police jacket is a short, bomber style made locally at Outdoor Outfitters in Toronto.  The jacket is lined with warm, waterproof thermoplastic polymer textiles, and the tightly-woven nylon shell keeps moisture out.

This jacket is logical, practical, and well-designed – everything about it has been meticulously planned. To stretch its use throughout the year, the lining zips out and storm cuffs at the end of the sleeve snap out. With safety in mind, reflective tape tabs can be pulled from the outside pockets, side zippers allow easy access to the belt, and expandable pleated armholes offer more movement.

This “action back” style  is reminiscent of early 20th century shooting jackets that allowed free upper body movement.  This bi-swing jacket style became popular during the 1930s, even with Hollywood actors including Clark Gable. See bi-swing jacket photos here.

Uniform safety and ergonomic updates

Police officers wear hatch gloves made of Kevlar, an extremely cut-resistant material also used to stop bullets in their bulletproof vests. The material “catches” bullets in its multilayer web of woven stronger-than-steel fibers. (The next post is dedicated to Kevlar, as it is a life-saving component of emergency uniforms.)

Because some uniform accessories “can be grabbed and yanked,” Supt. Tanouye explained, traditional pieces have been abandoned for safety’s sake. Proper long, knotted ties have been replaced with admittedly unstylish polyester clip-on ties, and the cross strap of the Sam Browne belt, worn to better balance the heavy police belt, was removed altogether.

TPS belts are  made from 3/8″ thick vinyl and carry a 4 lb gun, two magazines, first aid gear including a CPR mask and latex gloves, handcuffs, pepper spray, flashlight, and the very intimidating asp, an expanding baton made of extremely hard carbon steel that PC Cullingford shot out like a fishing rod. To collapse the thing, he had to push it into the floor by leaning his weight into it!

Without the Sam Browne cross strap however, the weight of the 14 lb belt must be taken on entirely by the pelvis and lower spine, leaving officers with sore hips, sore joints, and sometimes painful sciatica. Officers are switching to the two-belt system to balance weight via Velcro strips inside the belt and on the trouser waistband, and some  wear suspenders on their trousers for better weight distribution. Another option is to store smaller bits of belt gear in vest pockets.

Ira Janowitz, PT, CPE, an ergonomics consultant at U.C. San Francisco/Berkeley Ergonomics Program, conducted a study that explained police belt discomfort being due to the belt’s pressure and weight on the hip, pelvis, and lower back, exacerbated by the pressure of the belt’s edges and the grip of their weapon, belt stiffness, and “vertical location of the holster in relation to hip and pelvis and cant of the weapon.” (Read this excellent article about police belt ergonomics.)

Police services are attempting to combat the problems of the belt’s weight with ergonomically designed car seats for officers on the road. Flat car seats are currently used in Toronto squad cars, but Chrysler, GM, and Ford are designing cut-away seats to house the belts and take the weight off of officer’s lower body.

Clothing originally came from the need to protect against the elements and from predators, and the complex police uniform was created for the same reasons. Uniforms must be comfortable, well-designed, and made of cutting-edge textiles to protect officers from weather and from harm. Because the job can be literally life or death, the police uniform holds an enormous responsibility within its threads, but the TPS seem to be well-covered.

Thanks to Toronto Police Services 51 Division, and Constable Peter Cullingford and Superintendent John Tanouye for their help and assistance.

Uniform series: Toronto Fire Services

26 Jul

Adelaide Street Fire Hall – “the show must go on”.

When I was in university, part of my training as a costume designer was studying costume history, including military costume/uniforms. My original plan in life was to be a men’s clothing designer, so naturally I was drawn to the lines, durability, and practicality of military uniforms. Uniforms worn by emergency services like fire and police follow a very logical design for very specific purposes, with safety at top of mind.

Earlier this year, I visited the Adelaide Street Fire Hall, the busiest station in Canada, because I was interested in what pieces  make up the fire fighting uniform, what those pieces are made of, and what their purpose is. I was guided through the fire fighter uniform by Morgan Maschke, a fire fighter who impressed me with his textile knowledge – he seemed to know what materials were in every piece we looked at.

We started off by discussing “station fatigues”, the clothing worn at the fire hall and under any of the safety gear worn on fire calls. Firefighters wear shirts made of  a strong and hard-wearing fabric blend – 65% cotton and 35% polyester, with an embroidered Toronto Fire Services patch on the sleeve, and epaulets on the shoulders (epaulets are ornamental shoulder pieces used in the military for decoration or to display insignia). Navy or white t-shirts are worn under the shirts, emblazoned with a Toronto Fire Services crest.

Station trousers are made of the same poly-cotton blend, but the fabric is a thicker and harder-wearing twill weave for  long-lasting strength. Trousers are a flat front design (i.e. no pleats) and properly fitted to each firefighter. Morgan says “a good fit makes for a safer uniform”.  A webbed nylon belt is worn with the trousers with a plain buckle.

Though Morgan had me going for a minute about firefighters wearing red thongs under their trousers, we got back on track and discussed  under things – undies of the individual’s choice, and socks of an 80% cotton and 20% nylon blend – the addition of nylon strengthens the cotton. It may seem that a sock should be more substantial, given the work these men do, but as I was to find out, there is much more protection to go over this base layer.

Morgan in full firefighting gear.

Bunker pants and coats

When firefighters go out on a call, their protective clothing is already set up, very much like the way backstage quick-changes are pre-set in the theatre – they just have to step into their boots and pull up their pants, then pull on their head gear and jackets on the truck. In emergency situations, time is of the essence and firefighters have their dressing down to a well-timed science.

Once he’s down the pole, the firefighter steps into his steel-toed boots, made of heavy rubber with a nail-proof sole. These boots are insulated with felt and Kevlar, an amazing textile that is extremely strong and heat-resistant (more on Kevlar in a few weeks).

The legs of his fire pants, known as bunker pants, sit around each boot and are pulled up with suspenders. Pants have adjustable waistband buckles, close in the front with Velcro, feature cargo pockets to carry small tools, and have reflective tape stitched on for visibility in fires or at night. Firefighters are often crawling on the floor below the smoke of burning buildings, so their fire pants have thick pads made of 2 – 3 layers of Kevlar at the knees.

Once these are on, he can get on the truck and start driving. Bunker coats, helmets, and other items needed to do their job safely are stored in the cab of the fire truck. Bunker coats and pants are composed a thermal barrier of Kevlar and Nomex (another flame-resistant textile) with a water barrier,  made to measure and available in short, regular, and tall, just like a man’s suit (remember, safety in fit). The Kevlar/Nomex material is woven in a plain basket weave of rough threads with a quilted layer inside.

The sleeves contain a fitted cuff to protect the wrist and the fleshy part of the hand. Presumably, this feature also acts to secure the sleeve to the firefighter. Over these, thick suede gloves with wooly, insulated lining to withstand extreme heat are worn.

Head gear and SCBA

The first piece to go on a firefighter’s head is a rather Medieval-looking hood, made of a flame-resistant and thermally stable fiber called PBI, Polygenzimidarole. The textile is woven in a fine rib that will not burn or melt, staying intact even if it is charred. The hood is designed to cover the head, the entire neck, upper chest, upper back, with a 5″ elasticized hole for the face.

Morgan put his fire helmet on me so I could feel the weight – a firefighter must have a strong neck to hold this 5 lb piece up for long periods of time, and as I discovered, I just don’t have the build for it, but Morgan’s strong, stocky Scottish frame does well to hold up the weight of the whole uniform.

He  explained that after 911, the Toronto Fire Department joined in solidarity with the NYC Fire Department and adopted their helmet style. Each helmet is made of thick leather, completely adjustable for the individual wearer, with “jumbo” ear flaps, and is amazingly hand-made. Instead of a regal bald eagle, Toronto adopted Canada’s national emblem, the beaver, as their bronzed animal of choice affixed to the top of the helmet. A thick leather identification number sits at the front of the helmet, with a pull-down polycarbonate visor attached to the sides. Learn more about the helmets here.

Firefighters sometimes need a supply of oxygen when working in burning buildings, and for this, they wear a SCBA, self-contained breathing apparatus. The SCBA consists of an aluminum tank of compressed oxygen wrapped in Kevlar, containing  half an hour of air for normal breathing. The tank is attached to flame resistant shoulder straps and a waist belt with a seat belt-style buckle to secure it. The face piece is edged with synthetic rubber with and a clear polymer shield, and regulator clamps to both secure and fit it into place. To prevent condensation from breathing, nose and mouth caps fit inside of the face piece. Absolutely every inch of firefighter is covered.

It was a pleasure spending time at the Adelaide Fire Hall and learning about their uniforms. While I was there, I witnessed the brotherhood amongst the fire fighters – they had a pizza party that day, and a large group of them left the hall to visit one of their colleagues at a hospital who had been injured on the job. They live and work as a team; cooking, eating, and cleaning together, relying on each other for safety and efficiency in extremely dangerous conditions. Their highly-engineered uniforms help keep them safe and secure so they can confidently do one of the most dangerous jobs on earth. For more information about protective fire uniforms, see this DuPont page.

Thanks to the Toronto Fire Services South Command and special thanks to my guide, Morgan Maschke, of the Adelaide Street Fire hall. Next post will focus on uniforms of the Toronto Police Services.