The Commissioner is the most senior member of the fire department, and it is a civilian, non-uniformed office.

[6] He became a Deputy Chief in 1993, and in 1996, he oversaw the merging of the city's ambulance squads with the fire department.

[7] That same year, in retirement, Nigro was a member of an FDNY anti-terrorism task force.

[5] Regarding Nigro's appointment as Commissioner, New York City Mayor Bill de Blasio said: "Our administration is committed to building on this department’s impressive record, increasing diversity in the ranks, and improving response time and I know Daniel has what it takes to lead the FDNY forward".

[8] Nigro received an honorary doctorate of humane letters from Manhattan College in May of 2023, and delivered the Commencement address at the College's Graduate Commencement Ceremony.