He claims lack of maintenance has led to faulty sprinklers and faulty smoke alarms that is putting thousands of inmates and staff in danger.
Rikers Island is the world's largest jail complex, housing 14,000 inmates in 10 buildings and a staff of 9,000.
Doug Weidner knows every nook and cranny of Rikers having worked there for 20 years as a plumber. He came to Eyewitness News after discovering critical fire safety systems no longer working.
"When I was doing my inspections I noticed a lot of the systems were disabled," said Weidner.
When asked what he meant by disabled he answered, "Well, let's say the sprinkler and flow alarms fire alarms smoke alarms none of them were working."
Undercover video obtained from Riker's Island seems to back that up. In floor after floor in the Otis Bantum Jail, the smoke and fire alarm systems are disabled with blinking lights warning of power and system problems:
"It's not working, it's totally disabled and it's been like that for years," said Weidner.
Faulty fire alarm systems in a five-story jail housing more than 1,600 inmates in locked cells. But it gets worse.
"This is where I noticed none of the sprinkler systems in the cells were working properly," said Weidner.
Just days before he retired, the plumber also told us the sprinkler system in the jail did not work on some of the floors. Video obtained from inside the facility shows a sprinkler pipe that's been disconnected, an entire piece simply missing. Other video shows a fire emergency box with no hose.
Weidner says, "God forbid there's a fire there's going to be many lives lost, many lives."
Weidner detailed the problems in a memo last summer to the Director of Fire Safety on Rikers, soon after the department started ordering parts and making repairs. But months later, units housing 150 inmates still have no working sprinklers. Correction says they're still waiting for parts. Meantime, the smoke and fire alarms are inoperable throughout the entire jail.
"It's not working the way it was designed, no and you know if there's a fire if it's supposed to smell smoke set off an alarm its not gonna," adds Weidner.
Professor of Fire Safety Glenn Corbett says the video inside Otis Bantum Jail shows clear violations.
"That is very dangerous, particularly in a case like this where the building is actually very reliant on those systems because of course people are incarcerated and they don't have an ability to get out if they wanted to in a fire," said Corbett, Professor of Fire Safety at John Jay College.
But in the department's response to our investigation, a spokesman, Stephen Morello admits fire alarm systems are faulty throughout Rikers Island.
Hoffer: So there are no smoke alarm systems in Otis Bantum?
Morello: That is correct.
Hoffer: Is that true for other facilities as well?
Morello: Some of them yes.
Hoffer: Isn't that risky?
Morello: It's not ideal but when you have the kind of redundancy that we do functioning sprinklers everywhere, 10 fire extinguishers instead of 2, officers who are there, name me another institution that somebody who is looking in every corner of the building every 15 minutes.
Correction says installation of new fire and smoke alarms should begin sometime next year. The absence of the alarms make working sprinklers even more crucial, so why then with sprinklers not working in cells for 150 inmates are these brand new sprinkler heads still sitting unused in a box. The department insists inmates and staff are safe.
"Over the past 5 years more than a half million people have come in and out of the jails of New York City and there have been no injuries from fire," adds Morello.
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