High Explosives Preparation and Test Lab/Nuclear Chemistry Research Laboratory
Building number 167

Building 167 (originally Building 256) was an experimental preparation and testing laboratory for explosives, designed in 1928 as part of the Arsenal's rehabilitation project following the 1926 explosion. The style was Colonial Revival, matching its neighbors – it had a symmetrical south façade with a Georgian door surround, hipped roof , Flemish bond brickwork, brick quoins at the corners, copper gutters and flashing, and six-over-six windows. A 1938 remodeling included an addition to the structure, and the proportions and scale were further altered when the building was enlarged around 1948. The design was fairly faithful to the original style, with the new north bay on the street façade matching the original one, though the ridged hipped roof was not carried across. In 1951 the building was repurposed to function as a nuclear chemistry research laboratory, Picatinny having entered the Cold War era and turned to innovative, high-tech research. New ventilation stacks protruded from the original roof line, but otherwise the exterior was little changed.

Building Information

Year Built



One story, with cellar/crawlspace beneath original section; 30’ x 50’


One story, 45' x 57'


Additions in 1938 and 1945, major alterations in 1942 and 1951

A Building's Life

1928 blueprints show that as originally designed this building contained an office; two laboratory rooms; a mixing room; a charging room; and a hazardous test room. A small "L" at the rear (northwest) corner provided an entranceway to the main floor, and steps led down to a shallow cellar. In 1938 a 10-foot addition was built, apparently by WPA workers, and the cellar entranceway was enclosed in 1942. As was typical at Picatinny, over time many functions were carried out in this generalized lab space. A 1937 directory lists an "Initiator research" lab in Building 167, and a 1939 drawing shows alterations to a flare test compartment in the building. Oddly, Building 167 does not appear on a 1943 map of Picatinny, but its existence at that time is indicated by other building records. In 1945 a set of alteration and enlargement plans were drawn up, calling for a north extension (filling in the L) containing metal and chemical storage rooms and a mechanical mixing room – at that time, the building also had an optical dark room. The alterations appear to have been completed by 1948. Finally, in 1951 a full renovation updated this facility and ushered in the technological innovations of the second half of the 20th century, completely changing the interior arrangement. The new space contained an office; a change room; a "hot" lab and a "semi-hot" lab, both with new fume hoods and ventilation systems; a counting and measuring room; an electron microscopy room; a mass spectrometry room; and an isolation storage room. And, as if to defy the winds of change, there was also a glass-blowing room at the northeast corner, which served the many specialized glassware needs of Picatinny's research laboratories.

Building 167 1951 Equipment Layout Plan

Plans for installation of new equipment in 1951 (click on the image for a separate close-up view)

Building 167 Original Building Plan

1928 Buiding Plans (click on the image for a separate close-up view)

Building 167

Brick quoining and change in roof line show the seam between the original structure and the 1945 addition.

Additional Building Photographs

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Hot lab

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Basement beneath original section

building No. 167

Semi-hot lab

Building 167 Plans (click on the image for a separate close-up view)

  • Building 167 Section and Detail Plan