Which method does NOT help prevent the swallowing of harmful substances?

Wearing work uniforms does not directly prevent the swallowing of harmful substances in the same way that the other methods do. The primary purpose of a work uniform is to create a professional appearance, provide comfort, and sometimes protect against general dirt or contaminants. However, it does not specifically minimize exposure to chemicals or harmful substances that might be ingested.

In contrast, the other methods are focused on reducing the risk of ingesting harmful substances. For instance, proper storage of chemicals ensures that they are kept in safe conditions, minimizing the chance of spills or accidental access, thereby reducing the likelihood of accidental ingestion. Wearing work gloves can protect the skin from direct contact with hazardous materials, which in turn lowers the chance of transferring those substances to the mouth or food. Additionally, washing hands before meals is a crucial practice that directly addresses hygiene concerns, eliminating harmful residues that could be ingested.

In summary, while having a work uniform may contribute to overall safety and professionalism, it does not specifically address the risk of swallowing harmful substances as effectively as the other methods mentioned.