What is the first step in proper masking procedures?

In proper masking procedures, the initial step is crucial for ensuring personal safety in hazardous environments. When faced with a chemical, biological, or radiological threat, it is vital to prevent inhalation or exposure to harmful agents. Therefore, stopping breathing and closing your eyes serves as an immediate protective measure that limits the intake of contaminants during the critical moments when the protective mask is being donned. This action helps to reduce the risk of respiratory exposure before the mask can be properly put on, thus enhancing the overall effectiveness of the masking procedure. Following this step, the user would then proceed to don the protective mask and check its seal to ensure that it is airtight and provides maximum protection.