Surface/equipment  | 
        Number of alleles detected  | 
      
      
        RFU≥100  | 
        RFU≥50  | 
      
      
        Drawer of    laboratory cupboard (outside surface)  | 
        10  | 
        17  | 
      
      
        Laboratory    bench  | 
        12  | 
        19  | 
      
      
        Centrifuge    used for reference samples (outside surface)  | 
        1  | 
        5  | 
      
      
        Centrifuge    used for evidence samples (outside surface)  | 
        1  | 
        1  | 
      
      
        Container    with autoclaved tubes (outside surface)  | 
        0  | 
        1  | 
      
      
        Pipetholder    in laminar flow cabinet  | 
        0  | 
        1  | 
      
      
        On/off    button laminar flow cabinet  | 
        7  | 
        9  | 
      
      
        Container    with autoclaved filtertips  | 
        0  | 
        0  | 
      
      
        Handle    laboratory freezer  | 
        7  | 
        13  | 
      
      
        Handle    laboratory fridge  | 
        2  | 
        7  | 
      
      
        Box    containing centrifugal filter devices (outside surface)  | 
        1  | 
        5  | 
      
      
        Rack for    tubes (empty)  | 
        14  | 
        18  | 
      
      
        Vortex  | 
        3  | 
        7  | 
      
      
        Electronic    pipette  | 
        5  | 
        10  | 
      
      
        Outside laminar    flow cabinet (front side)  | 
        0  | 
        0  | 
      
      
        Inside laminar    flow cabinet (bottom)  | 
        0  | 
        0  | 
      
      
        Inside    pipetting liquid handler with UV lamp (left side)  | 
        0  | 
        0  | 
      
      
        Inside    pipetting liquid handler with UV lamp (right side)  | 
        0  | 
        0  | 
      
      
        Inside    pipetting liquid handler with UV lamp (bottom)  | 
        0  | 
        0  |