English: This photograph depicted a Centers for Disease Control (CDC) laboratorian, as he was putting on an older-model positive-pressure suit before entering one of the CDC’s earlier maximum containment, or Biosafety Laboratories (BSL), sometimes referred to as a “suit lab”. Scientists working within a BSL must wear protective garments that are air-tight, thereby, protecting the technician from exposure to highly-infectious pathogenic organisms. Fresh, filtered air is supplied to the interior of the suit via overhead tubing. The positive-pressurization offers some added protection to exposure through a defect in the suit, for if the suit’s patency is compromised, air would be forced out of the suit instead of being sucked into the suit.