Biosafety experts have expressed their concern about possible lapses in safety procedures related to how the Centers for Disease Control and Prevention (CDC) handle highly infectious pathogens they have stored in their laboratories.

Questions about the CDC's ability to ensure the safe handling of deadly diseases arose after USA Today published a report about an incident in 2009 where a decontamination chamber at one of the agency's top level facilities suddenly malfunctioned. The chamber stored strains of smallpox and Ebola.

According to documents presented by the newspaper, four of the agency's scientists entered the chamber for decontamination. The system failed to initiate, however, and the workers were not given the precautionary chemical shower.

The gasket seal on one of the chamber's doors began to deflate, forcing the scientists to hold on to it in order to keep it shut. When the back door into the laboratory also gave out, the four CDC workers executed an emergency maneuver to have themselves decontaminated. The alarms for the air pressure also started to go off and the safety monitors showed that the facility was in code red.

Richard Ebright, a specialist on biosafety at Rutgers University, compared the events outlined in the report as similar to those seen on a disaster movie. USA Today asked Ebright to review the CDC documents.

The report also mentioned emails from some CDC officials that showed they even tried to keep the incident under wraps, but eventually federal regulators were informed about it.

Ebright said the mishap in the CDC facility is indicative of failures that occur even in high level biocontainment laboratories, while the agency's attempted cover-up of the incident shows just how unreliable it is to police its own workers.

Previous Lapses In Safety Procedures

This is not the first time the CDC faced scrutiny for lapses in its safety procedures. In 2014, agency officials were called to two congressional hearings, with the first one involving the mishandling of bird flu samples and the second one involving the possible exposure of several employees to anthrax.

That same year, one of the CDC's laboratories was given a sample of the Ebola virus even though it was not equipped to work on such a pathogen.

When asked about the decontamination chamber mishap in 2009, the CDC said the workers in the facility were never really at any risk, despite the equipment failure. Safety engineers were immediately called in to help the scientists manually operate the chemical shower.

The agency believes that the failure stemmed from an error in the laboratory's system, which was addressed immediately.

"Yes, there was some malfunction, but there was a clearly established protocol for how to deal with the malfunction and that was quickly and rapidly executed," the CDC's laboratory safety expert Steve Monroe pointed out, adding that the potential safety risk would have only been minimal.