The U.S. Centers for Disease Control and Prevention says “[s]ome people are sensitive to molds. For these people, exposure to molds can cause symptoms such as nasal stuffiness, eye irritation, wheezing, or skin irritation. Some people, such as those with serious allergies to molds, may have more severe reactions.”

In April 2014, four Hilton Anchorage housekeepers reported personal health concerns to management they suspected might be mold-related.

On May 5, 2014, the Hilton Anchorage general manager wrote

[i]t is our conclusion the Hotel has, both in the past and continuing through the present, taken effective measures consistent with the guidelines and recommendations published by OSHA and the CDC to ensure that air quality at the Hotel is safe.

The hotel’s general manager went on to state:

While a very small number of employees have reported they suspect mold may be the cause of some of their personal health problems, at the present time the Hotel is not aware of any medical or other evidence to substantiate such suspicions.

The three molds strains that the Hilton Anchorage reported detecting on April 4, 2014—Ulocladium sp., Aspergillus/Penicillium-like, and Chaetomium sp.are potential indicators of water intrusion, according to Hilton documents. Hilton records provided to the Union show that Hilton has confronted pipe leaks since 2012.

On April 30, 2014, Hilton’s consultant advised

The source of any water intrusion should be identified and corrected, all water-damaged materials should be replaced, and subsequent mold growth properly cleaned up following the Institute of Inspection, Cleaning and Restoration Certification (UCRC) or USEPA guidelines.

During the summer and into September of 2014, Hilton contractors performed work on guest rooms having conditions conducive to mold. On October 1, 2014, the Union requested a description of all work that had been done. On October 10, 2014, Hilton management responded in part by stating that it had completed repairs in mid-September.

On December 3, 2014, management reported that testing conducted on October 23 and November 12 revealed mold in an additional guest room, which it said would be be repaired by outside contractors.