Tag Archives: DuPont

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.

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.

Tyvek, a decades-old textile you’ve never heard of

2 Jun

I took a stroll along Danforth Avenue last week and popped into a cute little gift shop to buy the leopard print umbrella in the window. As I wandered around the store, I spied an extremely cool men’s accessory that prompted this week’s post. Gents, this week I bring you tales of an old, largely unknown textile that has many uses,  a little number called Tyvek.

What the feck is Tyvek?

Look for "Tyvek" on the white sheet surrounding buildings under construction.

Tyvek is a durable, lightweight synthetic textile created by DuPont in 1955. It is a highly breathable, water-resistant material made of high-density polyethylene fibres that water vapor can pass through. It’s a material that may sound foreign to you, but I’m willing to bet you’ve already experienced it in some form or another.

Tyvek is used for products like courier and mailing envelopes, car covers, protective clothing, labels, wristbands, graphics, packaging, and house wrap, used in construction as “a weather-resistant barrier… [to] combat water, moisture and air infiltration that are any structure’s worst enemies. Allowed to penetrate behind siding, wind-driven rain and moisture can saturate walls, creating a breeding ground for mould, mildew and wood rot. The properties of DuPont™ Tyvek® do not support the growth of mould or mildew” (from the DuPont website).

How Tyvek is like felted wool

Polyethylene fibres of Tyvek

I reckon that Tyvek is the chemical alternative to felt in that it is made in a similar way. Felt is made of wool fibres compressed with pressure and heat and made into a usable textile. Similarly, Tyvek is made by the same process but with polyethylene fibres. To bring the fibres to a near-inpenetratable bond, Tyvek is created through a process called Spunbonding – polyethylene  filament is extruded through a spinneret, then heat is applied to fuse the fibres together. Neither felt nor Tyvek is woven – felted wool is not very strong and can be pulled apart, but Tyvek cannot be ripped or torn – it is virtually indestructible unless you take a blade to it and slice it up.

Can you recycle it?

I certainly hope so. It’s made of petrochemicals and it will be around longer than I will be so I think it’s a good idea to be able to deal with it responsibly. I started looking around and the information I found on the web complained of recycling with DuPont only if you were hip to shelling out for postage, but these sites are a few years old and the DuPont website insists that users can order their Waste Management Recycle Kit that comes with a prepaid return envelope.

Sounds great, but you have to pay $15 to order the kit. If you’re a conscious consumer and like to take environmental responsibility for products you use, you just might order the kit because $15 won’t break the bank and you can send back up to 250 square feet of Tyvek products – a good move for busy offices. Interested? Find out about the DuPont kit here.

Wearing Tyvek

Tyvek can also be made into clothing. Tyvek is used for protective clothing for people who might work with hazardous materials and chemicals, but did you know that those thin, blue hospital  shoe coverings are also made of Tyvek?

During the 80s, people gave Tyvek clothing a go, but it didn’t really pan out: somewhere around 1987 or 88, I was working in the Eaton’s casual menswear department at the same time the Beach Boys were making a comeback of some sort. One summer day while unpacking the stock for the Regina SK store as selected by Toronto ON buyers,  I pulled out six blue bomber-style jackets with ribbed cuffs and waistbands out of Tyvek with Beach Boys graphics all over them. Hard on the eyes and in a foreign, soft papery-plastic material that just felt plain weird, these jackets didn’t go over very well and I think I remember almost having to give those suckers away at the end of the season clearance.

I think Tyvek has to find the right people and the right people have to find Tyvek. In the late 1970s, this age of plastic material found its soul mate. New Wave syth-geek band, Devo, moved on stage like robots in their notorious two piece Tyvek suits topped by those kooky, stepped red hats. No one else could have pulled it off.

(For anyone interested, I found a concert video of Pearl Jam performing Whip It in full-on Devo costume!)

A super cool Tyvek accessory 

Devo immortalized in a Tyvek Dynomighty wallet

What caught my attention in the store were the most fun, lightweight, indestructible, $15 hipster wallets made of Tyvek by Dynomighty. These wallets have no glue or thread to hold them together – they’re folded. And they expand to cater to all of the crap that you know you’re going to stuff in there and you can keep on cramming because the textile won’t rip. Bonus!

You’ll have a hard time choosing a favourite with so many graphics available – will it be the map of the London Underground? The Campbell’s soup cans? The U.S.S. Enterprise? The sheet music? Or the Fonz? If you’re in Toronto, you can find Dynomighty wallets live an in person at Drysdale & Co. on the south side of Danforth and Broadview or online and global at drysdaleandco.com.

Another cool feature of the Dynomighty wallet is that it is recyclable, or at least that’s what their product videos say. This is a great website that discusses the wallets from a responsible ecological point of view and features the Dynomighty wallet video for your information.