Monument record ORF 160 - Laboratory 3 Climatic Testing, circa 1956

2007: Field survey of the Atomic Weapons Research Establishment by Historic England (S1).
Structure F8: The Climatic Testing Laboratory F2 originally comprised two buildings The Laboratory 126 and adjoining to the east the Condense Pump House 128. The Laboratory comprises a large reinforced concrete chamber oriented roughly north to south with a barrel vaulted roof, dexcribed in 1973 as a foam slag arch (PSA 1973). The main entrance to the building is to the south through a substantial reinforced concrete canopy, the southern side of which is protected by a shingle traverse supported by concrete wing walls. A set of metal plates attached to the underside of the canopy mark the position of a central overhead lifting beam that passed into the main chamber. To the east of the main doors is an attached brick building which housed switch gear and air conditioning plant. On the opposite wall are various fuse and switch boxes.

The main chamber is 24.50m (80ft 5ins) long and 6.0m (19ft 6ins) wide and is divided into two uneven cells, to the rear the north cell is 13.50 m (44ft 4ins)long. At the southern end of the chamber where the concrete floor is at the entrance level the chamber is 6.25m (20ft 6ins)high to its apex. Separating the two cells is a large step, 15.30m (50ft) from the rear, north wall, and the floor level drops by about 0.90m (3ft)in the north part of the chamber to the foundation level. The southern part of the chamber was the preparation area. It was originally sealed at the southern end by wooden doors. Subsequently crude steel framed doors have been attached to the exterior of the building. At eaves height three reinforced concrete tie beams support L shaped brackets for an overhead lifting beam which extended out into the external canopy area. The later steel doors have a cutout to accomodate this beam. The area was lit by fluorescent tubes and there are the remains of a secondary lighting system. On the walls to either side are the remains of cable ducting and small bore conduits for electical sockets. On the east wall there are also large diameter duct pipes probably for warm air. A passage to the west leads through to an attached switch room (below).

To the north is the large insulated chamber with a suspended floor carried on four concrete dwarf walls. The northern part of the chamber was originally separated from the southern section by an Expandomesh and plaster wall, remains of which are still in situ, which had a large metal door carried on an overhead rail whose mounting brackets remain, the door slid westwards into a slot in the access corridor to the small switch room to the west. The door to the north chamber remains but has been dislodged. Scattered remains of cork insulation board cover the areaIn the northwest corner a large access corridor leads west into Condense Pump House(see below). Fixed to the wall of the main chamber are various small bore water pipes and electrical conduits. On the rear wall of the chamber in the lower east corner is a large bore pipe that probably leads to an external vent. Also on the rear wall are two enclosed magazine type lights and the remains of two gauges with labels ‘TRYCHLORETHYLENE STRAINER INLET’ and ‘TRYCHLOROETHYLENE STRAINER OUTLET’. The northern part of this chamber and the plant room to the west was badly damaged by fire when it was hit by a stray missile during explosive ordnance disposal work (pers comm Grant Lohoar NT).

On the west side of the Laboratory is the Condense Pump House 128, this is a large rectangular reinforced concrete building, 16.98m (55ft 8ins)by 6.30m (20ft 8ins)and 4.30m (14ft 0ins) high). It comprises two self-contained rooms, to the south a small switch room and to the north the main plant chamber, both of which connect through to the main chamber.

The small electrical switch room to the south is entered from the passageway contained the sliding door to the northern part of the chamber. From the exterior, to the west, it was entered through a pair of double outward opening doors, which were protected by a later brick porch, opening was later sealed by a crude steel grating. A second set of outward opening wooden doors were also attached to the outward end of the porch. The room contains the remains of electrical switch gear and metal cable ducting, probably from monitoring equipment. The room was lit by enclosed electrical bulbs and a red pipe probably carried a CO2 fire suppressant system. An air conditioning duct runs longitudinally down the centre of the room. At the east end of the room the single door giving access into the main laboratory is aluminium clad.

The large plant room of the Condense Pump House was entered from the outside through a pair of outward opening wooden doors and was originally lit by two rectangular window in the west wall subsequently blocked in brick. To the south of the door opening is a frame that probably held carbon dioxide bottles for the fire suppressant system. Internally, are the remains of a large cooling plant on the north wall, with three vents to roof. There are also a number of concrete mounting blocks of various sizes and cable ducts in the floor. In the southwest corner is a large electrical switch box with several signs, including ‘LIGHTING’, ‘PLANT ROOM FANS AND PUMP’, ‘CALORIFIER PUMP’, ‘EXHAUST FAN’, and ‘UNIT HEATER’. Still attached to its walls are various small bore pipes, electrical conduits, box section cable ducts, lights and switches. In the north corner a large corridor runs eastwards to the northern end of the main chamber, the floor level of this corridor is the same as the lower floor level in the main chamber and reached by three steps down from the
plant room. Externally on the north side of the Plant Room is a cast concrete flanking wall retaining the shingle traverse and protecting a large rectangular air intake or vent with a metal grill over.

To the northwest of the plant room is an originally freestanding small rectangular building (3.52m (11ft 6ins) x 2.45 (8ft 0ins) and 2.45 (8ft 0ins) high) constructed of Burwell white bricks laid to English bond, which was formerly covered with a flat, steel framed, felted roof (now missing). It is entered from the east through a single wooden door opening with a concrete lintel. To the west is a wooden louvred vent and to the east originally was a small rectangular window subsequently blocked with red bricks. In the north wall are 5 pipe openings of various diameters. Internally are the remains of a switch and fuse box. The building might have been used to house a compressor.

This small block was subsequently extended to the south in red brick, which match those used to block the window. The new building was laid to English bond with closers with a rectangular window in the west side with a concrete lintel and a red tile sill. On the south side is a double wooden door, outward opening with a concrete lintel.

This extended building was subsequently linked to the main concrete plant room by the insertion of a new plant room and smaller toilet block, its north and south walls are constructed with red bricks cavity walls laid to stretcher bond, the west wall is laid to English bond and crudely tied in to the existing structure. Its roof is of reinforced concrete covered in asphalt. There are single outward opening wooden framed doors placed centrally in the southa nd north walls. In the north wall is also a metal framed 6-light window. The floor of the northern room is dissected by cable ducts and in the southeast corner are the remains of an electrical switch box and cable trunking. On the wall of this room are various electrical conduits, sockets, switches and lighting. The southern part of the extension was given over to a pair of toilet cubicles toilet and a washbasin compartment.

At the north end of the traverse is a large concrete cube 0.92 x 0.90 x 0.82m (3ft) with the remains of two steel channels set vertically in the top.

SCHEDULED ANCIENT MONUMENT (S2).