Have an attendance code? Sign In to enter it. This live web event has ended. Thank you for attending. Contributors Mark Gilligan, SE Mark is registered as a registered Civil and Structural Engineer in California with over 40 years of structural engineering experience designing a wide variety of building projects including residential remodels, residential and commercial buildings, research and teaching facilities, public schools and hospitals. He chairs the SEAOC Professional Practice Committee and previously chaired SEAONC’s Seismology and Construction Quality Assurance Committees.