34 Biosafety Manual The following table is a summary of general characteristics of the arthropod containment levels. For more specific criteria, reference the Arthropod Containment Guide mentioned above. General Characteristics of the Arthropod Containment Level Anthropod Containment Level 1 2 3 4 Infection Status Uninfected OR infected with nonpathogen Up to BSL-2 Up to BSL-3 BSL-4 Practices ACL-1 standard arthropod handling practices ACL-1 plus more rigorous disposal, signage, and limited access ACL-2 plus highly restricted access, training, and recordkeeping ACL-3 plus enhanced access restriction, extensive training, and full isolation Primary Barriers Speciesappropriate containers Speciesappropriate containers Escapeproof arthropod containers, glove boxes, BSC Escapeproof arthropod containers handled in cabinet or suit laboratory Secondary Barriers Separated from laboratories, double doors (2), sealed electrical/ plumbing openings. Breeding containers and harborages minimized. BSL-3 BSL-4 Cell and Tissue Culture Cell and tissue cultures may contain pathogenic organisms. It is prudent to consider all cell lines to be potentially infectious. Most cell and tissue cultures can be safely manipulated using BSL-2 practices and containment.