What Is the Shank in a Safety Shoe?

A client from the Middle East came to us with a real problem. Workers were complaining about foot pain. Shoes were deforming in 3 months. The cause was clear.

The shank is a rigid strip, usually 10–15 cm long, placed between the insole and outsole in the arch area of the shoe.¹ It is the structural core of the shoe. It distributes load, maintains arch support, and prevents the shoe from bending or warping under weight.

When I inspected the sample shoes that client brought, I found either no shank at all, or a thin plastic strip that provided almost no real support. Those shoes had passed basic EN ISO 20345 testing. But they were failing workers every single day on the job site. That is the gap between passing a test and building a shoe that actually performs. The shank is invisible from the outside, but it determines how long a shoe lasts and how a worker’s body holds up over a full shift.

What Does the Shank Actually Do in a Safety Shoe?

Picture a 90kg worker standing on the edge of a scaffold plank, all his weight pressing down through one foot. That arch is under serious load. Without a shank, something has to give.

The shank acts as a bridge across the arch. It spans the gap between heel and toe, distributes load evenly through the foot, and keeps the foot in its natural alignment. Without it, the midsole compresses unevenly, the outsole warps, and the foot loses proper support with every step.

We have run internal wear tests on shoes with and without shanks under simulated daily load conditions. The results are not subtle. Shoes without shanks showed visible arch deformation within 60 days². Workers wearing those shoes reported discomfort starting as early as week two. That is not a long time. Most workers expect a safety shoe to last 12 months or more. A shoe that fails structurally in two months is not just a comfort problem — it is a cost problem for the buyer and a health problem for the worker.

Why Arch Deformation Matters Beyond Comfort

When the arch of a safety shoe collapses, the damage goes further than the shoe itself.

A shank prevents all of this. It is not a comfort upgrade. It is the part of the shoe that makes every other part work the way it is supposed to.

What Materials Are Safety Shoe Shanks Made From?

When a buyer tells me they want a lightweight safety shoe, the first thing I think about internally is the shank. Shank material is one of the biggest decisions in the design of any safety shoe.

Safety shoe shanks are made from four main materials: steel, fiberglass, nylon or plastic, and carbon fiber. Each material has a different weight, rigidity, conductivity, and cost profile. The right choice depends on the work environment, the weight target, and the performance level the shoe needs to meet.

Here is how these four materials compare based on our actual production experience at Shoegan.

Shank Material Comparison: What the Differences Actually Mean

Steel shanks are the most common. They are strong and durable, and the cost at the component level is low. But in cold environments below -10°C, a steel shank conducts cold directly into the arch³. Workers feel it quickly. For electrical hazard zones or facilities that require workers to pass through metal detectors, steel is also the wrong choice.

Fiberglass shanks solve the conductivity problem. They are about 40% lighter than steel⁴ and carry no electrical or thermal risk. They are slightly less rigid under extreme load, but for most industrial environments, the difference is not meaningful in practice.

Nylon and plastic shanks are where I get cautious. They are cheap and light, but they flex too much under real industrial load.⁵ We only recommend them for light-duty environments or very short shifts. Some suppliers use them in shoes that look premium on the outside. Buyers should check this specifically when evaluating samples.

Carbon fiber is where we are seeing growing demand in the mid-to-high end market. One client based in Germany asked us to redesign their existing steel-shank model using a carbon fiber shank. The final shoe came out 180 grams lighter per pair⁶. Over an 8-hour shift with 8,000 to 10,000 steps, that difference is real to the worker wearing it.

Does Every Safety Shoe Need a Shank?

Not every safety shoe on the market includes one. And EN ISO 20345 does not list a shank as a standalone mandatory requirement⁷. So some suppliers skip it, especially at the lower price points.

Not every safety shoe requires a shank, but any shoe designed for workers who are on their feet for more than 6 hours a day does. Without a shank, the shoe cannot maintain its structure under the cumulative load of a full industrial shift. The shoe degrades faster, and so does the worker’s body.

In 15 years of production, I have never recommended a shank-free design to a buyer whose end users work on their feet through a full shift. The reasoning is simple arithmetic.

When a Shank Is Necessary vs. When It May Not Be

A construction worker does roughly 8,000 to 10,000 steps per shift.⁸ Every step puts load through the arch. Without a shank, the shoe absorbs that load in ways it was not designed to handle. The shoe wears out faster. The worker’s foot suffers faster. And the buyer receives complaints and return requests that could have been avoided at the design stage.

The only situations where we would consider a shank-free design acceptable are very light-duty environments, flat warehouse floors with short shifts, or roles where the worker is mostly seated. The moment the work environment becomes more demanding than that, a shank is no longer optional.

Is Steel Shank the Same as Steel Toe?

A procurement manager once sent me a spec sheet that listed "steel shank" under the toe protection requirements column. I see this kind of confusion regularly, even from experienced buyers. It leads to misspecified orders, incorrect production runs, and re-quoting that delays the entire project.

No. A steel shank and a steel toe are two separate components with completely different functions. The steel toe cap sits at the front of the shoe and protects against impact and compression. The shank sits under the arch and provides structural support. They are independent components, and each is specified separately.

Under EN ISO 20345, the toe cap must withstand 200 joules of impact force. That is its job. The shank has nothing to do with impact resistance. It is about keeping the shoe’s structure intact and keeping the foot properly supported across the full length of the shoe.

Steel Toe vs. Steel Shank: A Clear Breakdown

A shoe can have a composite toe cap with a steel shank. A shoe can have a steel toe cap with a fiberglass shank. These are independent decisions made based on what the job environment actually requires. Mixing them up in a specification does not just cause confusion — it changes the product you end up receiving. Getting this clear before you finalize any spec sheet saves time for everyone involved.

Conclusion

The shank is small, invisible, and easy to overlook — but it is what holds a safety shoe together under real working conditions. Specify it right, and everything else performs better.

At Shoegan, we help buyers make shank decisions that match their end users’ actual work environments — because a well-built shoe starts from the inside out.