TEMPERATURE/HUMIDITY EXPLOSION-PROOFED TEST CHAMBER

The purpose of this amendment is to incorporate FAR 52.237-1 "Site Visit" by reference and address questions received from industry as follows: 1. Section 4.4: "Powder paint" is specified. Is this to be powder coat, or exterior paint? Due to the custom nature of this chamber, enamel paint with automotive grade clear coat would be preferred, and would offer significant cost savings. Per 9/18/15 amendment, powder paint or enamel paint is acceptable. 2. Section 4.4: The chamber exterior cannot be Class 1 Div 1 Group C&D explosion resistant, and with NEMA-4 electrical. If the chamber exterior is to be explosion proof rated, then all control valves and electrical components must also be explosion proof rated, or enclosed in EP enclosures and junction boxes with rigid conduit and explosion proof seal-offs, which will add significantly to the exterior dimensions and to the cost. Class 1 Div 1 Group C&D explosion resistant is required on/in the chamber itself. The chamber will be located inside the explosion proof bay. All electric solenoids/valves will be located on the wall outside the explosion proof bay. 3. Section 4.4: Since NEMA-4 (outdoor) chamber construction is specified, outdoor humidity chambers in northern climates can cause problems with freezing drains, and also freezing humidity (steam) control valves when they are static and not being utilized. Will the chamber be required to operate in an unheated winter climate? The chamber location is not climate controlled so it may be operating in the freezing environment. 4. Section 4.4: The maximum chamber dimensions are problematic to comply with the air flow requirements, and the requirement of "the chamber must be usable without bending down". Is the 92" height requirement for move-in only, or is that a maximum installed height? What flexibility to exterior dimensions can be allowed to make one of the proposed layouts work? (See also #2, if explosion proof exterior is required additional height and/or depth is required for enclosures). We have to keep exterior dimensions due to moving the chamber along a ramp and making sharp turns around the corners. The height is limited by the entrance door and an overhead hoist located inside the bay. 5. Section 5: Does the remote control panel need to be NEMA-4 (outdoor) construction, or is NEMA 1 (indoor) adequate? Remote control panel will be located inside climate controlled space. Indoor protection is adequate. 6. Section 5: Is the chamber supplier responsible for 200' of interconnect between the chamber and controller...wire only, wire and conduit, neither, or both? You will need to provide all required wiring and coper tubing (up to 200') only. All wiring must be ran in existing wiring trays. Some conduit may be needed for connecting to main power. 7. Section 6: "Remote" refrigeration skid is required, as is "outdoor remote air-cooled condenser". Please identify the distance from the chamber to the remote refrigeration skid, and verify whether the refrigeration skid needs to be indoor or outdoor construction. Location of equipment as follows: Chamber will be inside explosion proof bay (indoors, not climate controlled). Electrical valves/solenoids will be installed on the outside wall of the explosion proof bay (indoors). Skid with refrigeration compressors will be located outside and near the explosion proof bay wall (indoors). Condenser installed outside the building (outdoors). Control panel with controller, chart recorder, and temperature limits will be located in the control room (indoors). See attached drawing for distances/locations. 8. Section 7: What is the average pressure of the "low pressure steam supply" at the installation site? Steam pressure is 10 to 15 PSI.