In many industrial areas, dust - due to its composition - poses a type of hazardous material, making it a major problem. Especially in the pharmaceutical industry, the composition of dust and the daily dust exposure are important issues for employees, as the particles produced during production are in the air at the workplace. Without further protective measures, these particles can make their way into the respiratory tracts of employees and there possibly lead to serious health consequences. Therefore, employee protection - for example in the environment of tablet production - is particularly important, since on the one hand the self-cleaning mechanism of the respiratory tract can no longer cope with or remove too much dust on its own, and on the other hand the active substances used can become a hazard if employees are exposed to them over a longer period of time.
Our blog article will inform you on how to protect your employees from hazardous dust.
In the production of medication, it is important to remove whirled-up particles from the air, so that employees do not come into contact with them. There are various measures to protect employees in the manufacture of pharmaceutical products. In the pharmaceutical environment, this form of employee protection is called containment.
When selecting a suitable containment measure, the production process plays an important role:
The choice of dust filter systems is large. For the tablet-production processes presented here, dedusting systems with engineered dust collection, ensuring that particles are drawn off through a vacuum effect after being whirled up and separated via a piping system in the filter system, are suitable. Active exhaust-air dedusters are deployed to prevent the dust-laden air from escaping into the environment during the production of powder granulates. These dedusting systems are often installed at the end of the process, where they absorb the so-called raw gas (= dust-laden air) and separate the dust particles from the air flow.
The primary purpose of the dedusting system therefore is the safe removal of the dust from the production area and thus from the direct danger zone for employees and their health. It is essential to precisely define the following five criteria for the selection of such equipment, and to choose the appropriate protective measures for the defined process with the substances described.
Not all dusts are alike
The dust in the pharmaceutical industry consists of the tablet ingredients. Included here - apart from the active ingredients in the tablets - are further components, which have an effect on the tablet or medication properties. Depending on the ingredients, the hazard degree to employees may vary: Not only the type of substance and its ingredients, but also the dose and how long employees are exposed to this substance during daily work are decisive for their health risk. For this purpose, a workplace-limit value is defined for each substance, the so-called OEL (Occupational Exposure Limit). It indicates how much of the substance may be contained in one cubic meter of air so that the employee is not exposed to any health hazard.
The basis for the OEL is formed by the "NOEL = No-Observable Effect Level". It specifies the daily dose at which a critical effect is just prevented. Other factors are taken into account for this daily dose, such as:
This results in the "ADE = Acceptable Daily (Worker) Exposure". This is the daily acceptable dose, which - related to the breathing air of one day - results in the OEL.In the pharmaceutical industry, the studies of manufacturers of these substances serve as a source for the evaluation of the substances.
When there is not sufficient information on a substance to determine the OEL and thus assess the hazard, classification systems are used. These are used to assign the substance to a hazard category (also called class or band). A common system known are the "Occupational Exposure Bands", or OEB for short. The lowest level applies to the least active substances, i.e. substances that are almost non-hazardous to non-hazardous. The highest level applies to the most active substances, i.e. those substances for which even a small amount is sufficient to pose a high hazard.
A classification of the production systems to be used is assigned with respect to the classification: Depending on version and system, it is possible for different amounts of dust to escape during the production process. Depending on the classification of the substance, the properties and features of the systems must then be selected. This means for example, that for less active substances of category OEB1, systems with little or no containment measures can be selected for employee protection, as the substance poses no danger.
In principle, it must be ensured that the amount of escaping substance from the selected system is always below the limit value of the same substance, in order to exclude hazards to employees.
The selected features of the filter system are specified on behalf of the determined OEL value of the substances used. In this, the entire process, meaning the entire personnel and material flow must be considered: The section with the highest requirements determines the OEB level for all components and thus also the filter system. For substances less critical, more simple measures are sufficient than for substances requiring a higher classification based on their toxicity.
To ensure process reliability during tablet production, regenerable filter systems are primarily used for efficient dedusting. In regenerable filter systems, the filter elements are dedusted with compressed air after set times to prevent premature clogging. This significantly increases the service life of the filter. As soon as the service life of the filter is reached and dust cannot be released from the filter despite regeneration, the filter must be changed. Filter changing is carried out under appropriate protective measures, which shall ensure that the operator and the direct environment do not come into contact with the substance. Various technical containment measures are available for the safe handling of the dedusting system.
The dust that is blown out of the filter cells during dedusting is collected together with the larger dust particles in a dust-collection container. This container must also be changed regularly. As when changing filter cells, it is just as important here, depending on the composition of the dust, to observe appropriate containment measures for ensuring employee protection.
In addition to the health hazards from the ingredients, there are also hazards posed by the existence of dust itself: In pharmaceutical companies, mainly organic substances are processed. These are usually flammable and enable under certain conditions that danger of explosion can exist in the process. Filter systems must therefore be equipped with appropriate features specifically for individual company requirements. An alternative here are dedusting systems designed explosion-proof, which meet the requirements of the ATEX Directive 2014/34 applicable to these systems.
Modern dedusting systems play a major role when it comes to employee health protection, environmental protection and process safety in the manufacture of pharmaceutical products. The following criteria should be clarified in advance to simplify the dedusting system selection for all parties involved, and thus ensure long-term employee protection:
By observing these five criteria, you should be able to select the optimum filter system for your company-specific requirements, ensuring a virtually dust-free and safe environment for your employees and long-term production of your products.