an enhanced biohazard detection system and a method for detecting , screening and analyzing biological agents are disclosed . the system incorporates an immunoassay detection device to provide a more robust , less expensive method for detecting biological agents in air samples collected at strategically located monitored sites . the immunodetection based assays may be used either in parallel with , or as a prescreening assay for , a polymerase chain reaction based assay for detecting and identifying biological agents in air samples .