Visible Damage : A permanent change in condition that is clearly evident by visual inspection without recourse to optical measuring or observation devices
NFPA 1931 Standard for Manufacturer's Design of Fire Department Ground Ladders, 2004 ed. https://www.nfpa.org/assets/files/AboutTheCodes/19 32/1932-A2004-ROP.pdf, (Std: Mfg Design of Fr Dept Gr Ladr - Amer) {419 NFC}