Nearly 40 employees of the New York ISO have begun their second week of living onsite amid the ongoing coronavirus outbreak.

The team of volunteers moved into trailers at two NYISO control centers near Albany, N.Y., on March 23. According to a fact sheet provided by the grid operator, the spread of the coronavirus, particularly in and around the state, prompted senior leadership to decide "additional steps were needed to ensure the health and safety of NYISO employees and grid reliability."

Gov. Andrew Cuomo during a March 31 news conference said New York has 75,795 confirmed coronavirus cases, more than any other state in the country.

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The volunteer sequester team living at sites in East Greenbush and Guilderland, N.Y., is made up of 31 grid operators, two managers, two facilities staff and two cafe workers. The trailers in which employees stay during non-work hours have electricity, cooking facilities and entertainment options.

Prior to moving in, employees were tested and confirmed not to have the virus.

Two teams of operators work at each site, and the sequestered staff is following social distancing guidelines. NYISO said control rooms also are cleaned according to Centers for Disease Control guidelines between each shift.

NYISO does not yet know when the sequestration will end, but backup operators exist if other employees need to be rotated in, the grid operator said.

New York's neighboring grid operators in the U.S. have not yet called on staff to remain on-site, but they have planned for the possibility.

ISO New England and PJM Interconnection both have put measures in place to keep their employees healthy, such as moving in-person meetings online or to the phone and setting up a work-from-home policy for those who are able to do so.

PJM has kept separate teams of operators working together in each of its control rooms instead of moving them between workspaces, said spokeswoman Susan Buehler. PJM also has moved to 12-hour shifts, thereby eliminating one shift change, and has put in place additional cleaning and disinfecting policies.

Additionally, PJM has cots, showers and food already on campus if needed. "But that's part of our plan every day of the week," Buehler said. "We are always ready. This is not new and only as needed."

The ISO-NE has split system operations shifts between its main control center and backup center to minimize the potential for cross-contamination between crews and allow for more frequent cleaning, spokesman Matt Kakley said. The grid operator has contingency plans in place to ask essential operations and IT staff to remain on-site if needed to manage the region's bulk power system, he said, adding that no decision has been made to implement those plans at this point.

Across the country, the California ISO is not sequestering control center staff on-site but has been taking certain precautions since the outbreak started, including keeping staff members at the ISO's two control centers separate, said spokeswoman Anne Gonzales.

CAISO also has added staff screening protocols, including taking employees' temperatures before they enter the building and conducting verbal and visual checks for possible symptoms.

The Southwest Power Pool has contingency plans to ensure it is able to maintain reliability across the region but currently has no plans to sequester staff on-site, spokesman Derek Wingfield said. According to SPP's website, the grid operator's coronavirus response includes temperature checks for anyone entering an SPP facility and keeping operations staff working at a single location.

As for the Midcontinent ISO, that grid operator continues to take precautions to protect core operations employees who support the control room and key information technology and markets functions, said spokeswoman Allison Bermudez. However, they are not required to live on-site at this time, she said. For other personnel, a work-from-home policy is in effect to reduce employee exposure to the virus while maintaining business operations.