Howard County’s Savage library branch is closed Tuesday and Wednesday as repairs are completed on the building’s HVAC system.

The Savage Branch abruptly closed in November after several employees reported feeling sick and at least two wound up in the emergency room, where they say they were diagnosed with carbon monoxide poisoning. The 34-year-old branch in Laurel remained closed for three weeks.

This week, new components are being installed to the library’s HVAC system. Once the work is done, the system will run for testing throughout Tuesday and Wednesday, Sahana Callahan, a library spokesperson, said in a statement. The same independent, certified industrial hygienist who tested the branch before the December reopening will be on site on Wednesday to conduct eight hours of standard testing.

While county officials indicated that Savage could reopen as early as Tuesday afternoon, the library system is proceeding “with extra care,” Callahan said. Library officials anticipate that the branch will reopen on Thursday.

Despite county officials stating there was no confirmed source of carbon monoxide in the library in November, 21 carbon monoxide/gas detectors were installed at the Savage branch before it reopened in December.