The story of a small value that achieved great things: the MAK value
Anyone who works in mines, quarries, or in the processing of quartz sand—such as grinding it into a fine powder—is familiar with the occupational safety issue of fine dust. But few people know that the protective regulations governing this issue have undergone a long and fascinating development. Today, in Throwback Thursday, we take a look at a particularly important value: the MAK value.
“MAK” stands for maximum workplace concentration and describes the highest permissible concentration of a substance in the air at which no damage to health is to be expected.
The first MAK values were published in 1956 by the German Research Foundation (DFG) MAK Commission. Until the 1960s, legislators’ approach to dust in the workplace was still a long way from today’s standards. Dust was already considered a potential health risk, but the measurement methods were inaccurate. The actual mass of dust was not measured; instead, the number of visible particles in the air was usually counted.
It is also interesting to note how many companies attempted to improve workplace safety until the 1950s. Technical extraction systems and respirators, which are now standard equipment, were not yet widely used. Instead, many companies relied on medical or so-called “preventive” measures.
In many companies, for example, milk was regularly distributed—especially in workplaces with high dust exposure. At the time, it was hoped that milk could “bind” the dust in the body or cleanse the respiratory tract. Today we know that this does not work. Dust is ultimately inhaled and does not end up in the stomach.
Dust protection began earlier in quartz works: as early as the 1930s, Otto Lindemann worked closely with the employers’ liability insurance association and the trade supervisory authority to actively promote the protection of employees. In addition to the daily milk ration, the latest technology was already being used at that time to prevent dust in the workplace. Some technical measures, such as an air shower cabin, were designed by Otto Lindemann himself.
A turning point: the Johannesburg Convention
An important step toward modern dust measurement was the so-called “Johannesburg Convention.” It was adopted in February 1959 at an international pneumoconiosis conference in Johannesburg, South Africa. The aim was to establish uniform global standards for determining which dust particles are considered hazardous to health and how they should be measured.
In 1971, binding MAK values were finally introduced for the first time, primarily to protect against potential health risks.
This marked the beginning of modern and comparable dust measurement. The analytical methods that are still used today were also developed during this period.
In 2005, the MAK values were officially replaced by occupational exposure limits (OELs). Nevertheless, they remain important today and continue to be revised annually by the MAK Commission. While MAK values were legally binding until 2005, they have since served as the scientific basis for new AGWs. These are reviewed by the Committee on Hazardous Substances (AGS) and, if necessary, incorporated into the Hazardous Substances Ordinance as binding limit values.
Today, modern measuring devices, clear limit values, regular tests, and risk assessments ensure that employees are protected as well as possible. The MAK value thus contributes to making the workplace safer every day.
And that is precisely why this is a story that can be told again and again.
Incidentally, in 2006, quartz manufacturers played a key role in establishing the social dialogue on “quartz dust.” (Further information: Home | Nepsi | The European Network on Silica)
