Two more workers reported symptoms consistent with tank vapors Monday afternoon at Hanford.
They bring the total number of workers receiving medical evaluations for possible tank vapor exposure since March to 36.
In the Monday incident the workers reported smelling an odor.
Although their symptoms were not made public, typical symptoms of chemical vapor exposure include persistent coughing, headaches and shortness of breath. Hanford workers are concerned the vapors could lead to serious long-term health problems.
The two workers, one a Washington River Protection Solutions employee and the other a Mission Support Alliance employee, were evaluated by medical professionals and released to return to work Monday.
They were at a laundry trailer outside the SY Tank Farm when they developed symptoms. Vapors have been reported at the SY Tank Farm at least twice before this spring.
Industrial hygiene technicians were taking samples in the area Monday and checking for potential sources. No work was underway inside the SY Tank Farm with the smell was reported, according to Washington River Protection Solutions.