Learning Safety First

At Heraeus Quarzglas safety at work is a top priority. In addition to safe procedures and protective clothing made of DuPont™ Nomex® fibre, the firm relies on the fact that its employees are trained to be extremely aware of the importance of safe working practices. A glance at the training workshop shows how this can be achieved in a simple way.

As a major manufacturer of quartz glass worldwide, Heraeus Quarzglas develops, produces and processes high-tech products for applications in the solar and semiconductor industry and for telecommunications. Most production processes are very hot, requiring working temperatures of up to 2600 degrees Celsius. Technical safety precautions therefore have to be just as extreme. Most processes are completely automated. Warning signs remind workers of the risk potential. Information boards draw attention to correct conduct. And protective suits made of DuPont™ Nomex® are worn for protection. Yet ultimately the workers themselves contribute the most towards occupational safety with their responsible conduct. Health and safety are therefore central parts of the firm’s apprenticeship programmes, which focus on three areas: increasing awareness of potential dangers, understanding the meaning of protective equipment, and learning preventive behaviours.


Cooking steak to make an impression
Especially young, inexperienced people are at risk of making mistakes. Therefore one of the things taught right at the start of the training is the danger presented by hot glass. The firm creates realistic experiences and visual impressions which speak louder than words. For example, a raw steak is placed on a table and a heated glass tube is laid on top of it. As soon as it touches the hot glass, the water in the steak evaporates and the meat hisses and shrinks. This example of what can happen to human skin leaves a lasting impression with apprentices, ensuring that their attention is sharply focused on the need for protective clothing instead of cotton T-shirts and shorts.


PPE just like that worn by the professionals
Every trainee receives the same Personal Protective Equipment (PPE), also worn in the hot areas of glass production. For the past 12 years the firm has been using protective suits made of Nomex®, manufactured by the protective-clothing specialist ROFA and obtained via Werner Reitz GmbH. The suits provide extremely good protection from heat and flames, but are significantly lighter than clothing produced from non-flammable cotton. They are about as comfortable to wear as normal work clothes. They also allow for good freedom of movement, a clear advantage for manual activities and the finely coordinated work involved in glass blowing. Another advantage of light protective clothing is the higher degree of comfort, which is not only good for physical well-being, but also frees up the head so that greater attention can be given to the job. This means that fewer occupational accidents have been registered at Heraeus Quarzglas since suits made of Nomex® were introduced. There is also an additional motivation factor to be borne in mind: when trainees wear protective clothing just like the professionals, they feel they are as important to the firm as their older colleagues.


How does protective clothing work?
When a trainee is given protective clothing, he also receives an explanation of how it works and what protection he can expect from it. The extremely high temperatures reached during processing rule out the use of normal work clothing made of polyester or cotton, as once in contact with hot or liquid glass, it would burst into flame or fuse to the skin. By contrast, the garments made of Nomex® worn at the firm are non-flammable even when exposed to great heat, and do not melt. When exposed to extreme heat, air pockets inside the Nomex® fibres inflate and thus increase the insulation layer between heat and skin. This creates a protective barrier between skin and heat source and thus helps to prevent burns. The better these important notions are understood by trainees, the greater their awareness of the reason for PPE and the necessity of wearing it correctly.


The limits of protective clothing
Yet in order to prevent the incorrect use of protective garments, trainees must understand that even the best PPE has its limits. Wearers should in fact bear in mind that although PPE will protect for a while in an emergency, this protection is not indefinite. It is therefore important to consider not only the fracturing behaviour of garments, but also the level of thermal insulation they can deliver.


Flame-exposure test on DuPont™ Thermo-Man®
The Thermo-Man® test indicates whether clothing can withstand exposure to flames, to what extent heat is conducted through the clothing to the skin, the quality of the clothing as well as the consequences this may have for the wearer. Such a test was also performed on the suits made of Nomex® used at Heraeus Quarzglas, revealing that the suit’s outer layer does not break open during exposure to flames, whereas a cotton garment would be completely burned away. This means that the the suit made of Nomex® offers a better protection of the skin from the effects of direct exposure to flames.