Interval, Travel : The elapsed time starting when the responding vehicle wheels begin rolling toward the address or incident and ending when the vehicle arrives on scene at the address or incident location
NFPA 45 Standard on Fire Protection for Laboratories Using Chemicals, 2004 ed. http://eetd-safety.lbl.gov/sites/all/files/NFPA%20 45-2015%20LBNL%20Class%20Slides.pdf, (Std: Fr Prac for Lab Using Chem - Amer) {204 NFC}