While most of lower Man­hattan was without power, one key building remained lighted: 60 Hudson Street, one of the most important Internet hubs worldwide. Even during the worst of the storm, the building kept the country connected through an array of well-maintained generators…

Property manager Shaun Mooney, former Marine and volunteer firefighter, describes this job as “Mis­sion Critical”—“the lights have to stay on no matter what.” Preparation for Sandy started the week before the storm, with staff meetings devoted to assessing supplies and personnel needs. When power in lower Manhattan went out on Monday eve­ning, chief engineer Ernesto Martinez’s team monitored generators and pressure sen­sors. To make sure windows didn’t blow out, his team opened select airway chan­nels throughout the building to equalize pressure.

The group slept in cots and sleeping bags “in just about every uncomfortable place we could,” Martinez said with a laugh. “It decreases sleep time,” he added. He arrived Sunday and didn’t leave until Wednesday evening.