Two workers suffered skin contamination in separate incidents last month at Los Alamos National Laboratory’s plutonium facility, the latest in a series of worker-safety lapses at the lab.

In one incident, an alarm went off when monitoring equipment detected radioactive contaminants on an employee’s hand as he was preparing to leave the room.

A survey of the room traced it to contaminated residue on a phone, which workers can use while not wearing protective gloves, according to the Defense Nuclear Facilities Safety Board’s Jan. 12 report.

The other event involved a radioactive particle from a room where workers handle heat source plutonium, used for powering some satellite systems and spacecraft. A crew surveying that room couldn’t find the contamination, the report said.

Both workers were promptly decontaminated, and neither incurred a radioactive dose, lab spokesman Steven Horak wrote in an email.

The lab is taking actions to prevent similar events from recurring, Horak wrote.

They include “adding more detailed surveys of equipment that may be touched with bare hands while accessing these rooms,” he added.

Personnel remove their protective gloves before using the phone, Horak wrote, so they don’t put the potentially irradiated gloves close to their faces and breathe in contaminants.

As is standard when employees are exposed to radioactivity in work areas, investigators will look at the possible cause — in this case, how the phone became contaminated, the safety board indicated in the report.

The board noted this was the latest in a series of incidents in which workers were contaminated, saying the trend required analysis and corrective action.

“These events along with earlier lower magnitude contamination events are being looked at together to improve processes with the intent of reducing contamination events,” a board inspector wrote in the report.

In December, a worker’s forearm was contaminated by radioactive residue while disassembling old equipment despite wearing full protective gear.

That happened a week after a radioactive particle contaminated the skin of an employee who wore booties and a lab coat for protection while escorting carpenters into a workroom.

The light protective wear was allowed because the room was supposed to have been decontaminated.

That same month, workers evacuated a section of the plutonium facility after a newly installed glove box — a sealed compartment used for handling radioactive materials — released high levels of volatile organic compounds.

In September, a glove box breach contaminated a worker and produced a corrosive residue under the sealed compartment where radioactive material is handled

Corrective actions will include additional surveying of items, such as telephones, that can be touched without gloves in work areas where radioactive materials are handled, the board said.

The board also recommended closely observing workers to ensure they are complying with guidelines to protect them from radiation, assessing how the safety program and protective gear might be improved and looking for a common cause in contamination events.

The lab is taking those steps, Horak wrote, “to ensure our work practices and safety systems protect workers to the maximum extent possible.”

A longtime lab critic has linked the rash of worker-safety incidents at LANL to the plutonium facility growing more crowded and busy as the lab pursues production of bowling-ball-size nuclear warhead triggers, known as pits.

Greg Mello, executive director of the Los Alamos Study Group, wrote in an email the two latest incidents weren’t too serious.

“Nice to see things reported, though it would be preferable to have nothing to report,” Mello wrote.