Safety
The key feature of a safety shoe, accredited with an international standard, is a toe cap capable of withstanding the impact of a wedge-shaped steel 20 kg weight falling vertically from a height of one meter, absorbing 200 joules of kinetic energy. Toe caps are traditionally made from high impact steels and plastic toe caps.
However, most modern safety shoes incorporate other safety features that certify them to different classifications. These include steels plates moulded within the soles to prevent penetration underfoot from nails and other objects.
Other features relate to the sole. Slip resistance (forward movement) and grip (backward movement) which must also comply with standards, are also obviously important.
Other safety features in the sole include a prescribed minimum anti-static property, resistance to Antistatic, oil and chemicals such as acids and alkalis.
Comfort & Hygiene
Besides being safe, safety shoes must also be comfortable as workers often have to 'live' in them for extended hours. A worker wearing comfortable safety shoes is likely to be more productive and less likely to suffer chronic foot or leg problems.
Principal comfort features include shoe upper materials that pass a certain level of water resistance and breathability, lining materials need comfortable.
Other comfort features would include sole designs that provide adequate good fit, foot and arch support, flexibility, underfoot cushioning and heel impact absorption.
Durability
Safety shoes are mainly made of cow or buffalo hides. Soles are usually injected directly on to the upper so that a near perfect bonding is achieved, minimizing the chance of the sole separation and fluid or particle ingress.
Soles have high wear, tear, cut and puncture resistant qualities; thereby remaining safe and lasting acceptable periods under even the most testing working environments.