Bermbeveiliging Geleiderailsystemen ESP ESP ESP Plus W1 N2 / W1 / B Containment level N2 Class of working width W1 ASI B ESP 4.0 N2 / W5 / A Containment level N2 Class of working width W5 ASI A ESP 2.0 N2 / W4 / A Containment level N2 Class of working width W4 ASI A