pushed out into the environment by the exhaust fans through an elevated
stack. From the perspective of the worker, individual airflow requirements were
segmented-- major tritium handling systems were enclosed in high velocity air
hoods; work was performed through gloves in the ventilated hood enclosure
doors, or through accessible hood openings. The high air velocity hoods were
maintained at a pressure that was negative with respect to the surrounding
room spaces; most importantly, any tritium releases that occurred due to
normal operations, component failure, and/or operator error would occur inside
the hoods. The high-velocity air flowing through the building, and then through
the hoods, would sweep any released tritium away from the worker.
Although this combination of single-pass ventilation systems and high air
velocity hoods was used quite extensively-- and quite successfully-- for basic
worker protection, the protection of personnel living or working downwind was
dependent on the massive dilution factors that could be gained by the use of
By the end of the first decade, it gradually became obvious that the protection
of personnel living or working downwind could no longer remain dependent on
massive dilution factors. In their initial attempts at controlling tritium releases, a
newer generation of tritium design personnel developed a plan to control
releases by tightening design controls and material selection requirements.
After only a few years, however, it also became obvious that the techniques
developed, although helpful, would not be completely successful. While many
valuable lessons were learned, tritium releases continued to occur despite
more stringent design, material, and performance requirements.
By the late 1960s and early 1970s, it finally became obvious that a more
realistic tritium operating philosophy would have to be developed, one that
would not only protect the worker, but would also substantially increase the
basic protection of the public and the environment.