NKAK192001_QUESTIONS-AND-RESPONSES_24AUG2020.pdf

QUESTIONS AND RESPONSES

Project # NKAK192001 – Repair Fire Suppression, BLDG 207

**CURRENT AS OF 24AUG2020**

1. In reference to Section 01 14 19 Coordination, Page 01 14 19-6 Protection of existing facilities, Paragraph #2, please provide existing HVAC system drawings in order to determine the number of filters required.

This facility has been renovated multiple times since original construction. We do not have a comprehensive, up-to-date drawing of the entire HVAC system showing all filter locations. That being said, the majority of construction work in the scope of work for this project will take place in the main hangar bay and mechanical room where there are no HVAC filters. The location of filters in the areas where construction work does take place in conditioned spaces will need to be field verified.

2. Is the general contractor required to provide fire watch once the foam system is demolished until the new foam system is installed?

No, the existing foam system is currently locked out and not in use.

3. We need the location of the three existing pump houses & the site underground size and routing to this hangar to size our piping for the HEF System.

There are 3 pump houses (Buildings 219, 251 and 292) connected by a 16 inch water main line to provide redundant pumping capacity for all of the hangar fire suppression systems. See Attachment A (Flight Line Fire Suppression Map) and Attachment B (Old Plan Drawings with Civil Site Plan)

4. Does the existing system for the hangar overhead tie back into the new fire pump system supplying the HEF System?

The new fire pump system only feeds the new foam system.

5. For testing purposes, is the govt. responsible for removal of the airplane maintenance scaffolding?

Yes, government will be responsible for removal of the scaffolding.

6. Please provide a section view of the hanger to identify applicable elevations.

Per note 18 on sheet FX501 the contractor shall verify/survey all elevations and locations prior to installation. See Attachment C (Old Plan Drawings with Elevations).

7. Specification Section 21 13 25 paragraph 1.3.7.b. requires combined hydraulic demand of high expansion foam system and hangar bay sprinkler systems. The scope of work of this project calls for the sprinkler systems to remain. Please provide as-built drawings and hydraulic calculations of the hangar sprinkler systems so we can determine what pressure the High Expansion Foam system is to be balanced to.

Please reference the attached “as-built” drawings for the existing hangar bay sprinkler systems. These are for reference only. The contractor shall verify the actual as-built conditions of the sprinkler systems (i.e. pipe diameters, pipe lengths, etc.) prior to performing their hydraulic calculations. See Attachment D (As-Built Drawings with Sprinkler Layout).

8. Drawing FX102: May the feed main depicted from the west riser to the fire pump room be reutilized?

All piping associated with the new foam systems shall be new, including the main from the west riser to the fire pump/foam room. RE: 1/FX101

9. Drawing FX110: May the feed main from the fire pump room to the hangar be reutilized?

All piping associated with the new foam systems shall be new, including the main from the fire pump/foam room to the hangar bay. RE: 1/FX101

10. Drawing FX401 Detail-1: The test header is depicted at the east end of the south wall.

During the site visit it was identified that this space is currently occupied by a gas meter.

Please advise where the test header is to be located.

As noted on Sheet FX501, notes 22 and 17: The layouts provided are diagrammatical in nature only. The contractor shall be responsible for avoiding all conflicts and obstructions.

11. Are there as-built drawings available that show the hanger bay elevations?

See response to question 6.

12. Can the existing smoke curtain remain?

If the existing draft curtains meet the area requirements of UFC 4-211-01 and NFPA 409 and can be properly coordinated with the contractor’s foam system layout, then they are permitted to be reused.

13. Can the new smoke curtains be of like materials as the existing?

Draft curtains shall be designed and constructed in accordance with UFC 4-211-01 and

NFPA 409.

14. Note #9 on Sheet FX501 says that “The locations of the IR flame detectors shall exactly match locations indicated by the manufacturer as shown on FX111.” Do detector 3D mapping drawings needs to be generated by the design-build team to prove the three detector coverage requirement and to provide the detectors are not viewing outside the doors more than 5 feet?

Per Section 21 13 25, Paragraph 1.4, SD-02, d, the flame detector shop drawings shall be provided by Det-Tronics.

15. Note #9 on Sheet FX501 says that “The locations of the IR flame detectors shall exactly match locations indicated by the manufacturer as shown on FX111.” What is the desired height and aiming location of each IR flame detector? Are Field of View Limiters required to be provided on any of the IR Flame detectors?

Per Section 21 13 25, Paragraph 1.4, SD-02, d, the flame detector shop drawings shall be provided by Det-Tronics. The contractor must contract directly with Det-Tronics to develop the releasing system shop drawings and perform all testing.

16. It appears that the IR Flame Detector design has already been completed by Det-Tronics.

Can the Det-Tronics design drawings be provided so these design services do not have to be paid for again by the contractor?

Per Section 21 13 25, Paragraph 1.4, SD-02, d, the flame detector shop drawings shall be provided by Det-Tronics. The contractor must contract directly with Det-Tronics to develop the releasing system shop drawings and perform all testing.

17. It is understood that the US Air Force is considering alternative fire suppression options in lieu of high expansion foam that has been considered an acceptable alternative. Will the US Air Force and LRAFB allow options to be considered? If so, what documentation would need to be provided with the proposal for these alternatives?

No, our intent is to replace the existing HEF fire suppression system. Alternative options will not be considered.

18. The specification 21 13 25 discusses foam containment. Is the hangar provided with existing trench drains and oil water separator that discharge to a containment tank? If not, is this work to be included as part of this project?

There are existing trench drains on each end of the hangar bay, however they discharge directly into the storm sewer; not into a containment tank. A trench drain and oil water separator are not within the scope of this project.

19. Is the hangar door provided with separate and dedicated power as referenced in UFC 4- 211-01, Section 3-7.2 to achieve interior firefighting accessibility as referenced in UFC 4-211-01, Section 3-3.1.12? If not, since this is a fire protection upgrade should this be included in the scope of work?

Power for the hangar door is not included in the scope of this project.

20. Does the existing Notifier 640 panel have adequate capacity to handle the new voice message and the additional devices without adding additional boards and cards?

Contractor shall verify and provide any required expansion cards per section 28 31 76.

21. Will accurate as-built fire alarm (showing circuitry) and fire suppression drawings be available after award?

This facility has been renovated multiple times since the original construction. We do not have a comprehensive set of up-to-date fire alarm and fire suppression drawings. We can research and provide drawings from past projects we have on file on file on an as-needed basis

22. Note #1 on Sheet FX501 indicates the foam generator shown as part of the design have a required flow of 108 gpm and a pressure of 40 psi. Based on these design details what manufacturer foam generators and foam concentrate shall be utilized to achieve the compliance with the 90% coverage and 1 meter depth requirements of UFC 4-211-01 as reflected in these design drawings? If the design has been completed by the Fire Protection Engineer of Record, please provide all design details so additional design costs are not incurred as the fire protection systems, including the location and size of all foam generators will be installed as shown on these design drawings.

The system layout and generator performance are provided for reference only to show what the basis of design utilized. The contractor shall provide a complete system design in accordance with Section 21 13 25. The contractor shall be responsible for providing the Fire Protection Specialist as required by Section 21 13 25, Paragraph 1.5.1.

23. Note #1 on Sheet FX501 indicates the existing wet pipe will remain but “will be modified as necessary to accommodate the foam suppression system”. Can you clarify the wet pipe system modifications required so these costs can be included in the fee proposal?

Contractor shall be responsible determining what modifications will be necessary based on their design per Section 21 13 13.00 10.

24. If modifications are required to be made to the existing overhead wet pipe system, are hydraulic calculations required to be performed? If so, what C factor should be utilized for the existing piping?

Contractor shall be responsible determining what modifications will be necessary based on their design and utilizing the proper C-factors outlined in NFPA 13 per Section 21 13

13.00 10.

25. Has it been confirmed by the Fire Protection Engineer of Record that a fire pump is required for this project since the site water supply includes multiple 2500 gpm fire pumps at both 100 and 115 psi? Fire Pump spec 21 30 00 requires a 1500 gpm at 90 psi fire pump, which will require high pressure fitting and components downstream of the fire pump, including the fire pump itself. Please confirm the fire pump chosen by the Fire Protection Engineer of Record is rated for high pressure or determine if a 1500 gpm will need to be sole sourced due to the pressure rating.

The contractor shall provide equipment downstream of the new fire pump based on their hydraulic calculations. Where pressures exceed 175 psi, high pressure rated equipment shall be provided.

26. Is a specific C factor to be used when performing the hydraulic calculations for the foam system for any of the existing piping (both in-building and underground)?

C-factor requirements are provided in Sections 21 13 13.00 10 and 21 13 25.

27. Can the water supply data be provided for what flow and pressure is available on the supply line to Hangar 207 from the existing flightline fire protection water distribution system?

This will need to be addressed by the government/Base CE.

28. Were any internal pipe inspections performed by the Fire Protection Engineer of Record to validate the condition of existing piping and to determine the C factor to be used for any new hydraulic calculations?

Internal pipe inspections have not been performed. C-factor requirements are provided in Sections 21 13 13.00 10 and 21 13 25.

29. What is the height of the hangar bay (building sections were not provided) and the proposed height of the high expansion foam generators? This information is needed to validate required system demand pressures, fire pump sizing and the potential for a pressure reducing valve.

See response to question # 6. The HEF generators shall be installed per UFC 4-211-01 in the roof structure.

30. The required 36” clearance for maintenance around the pumps and equipment, and in front of electrical equipment appears to be a challenge given the layout of the foam/fire pump room shown on Sheet FX401. Can the equipment be installed as shown without any push-back from the DFPE or LR-AFB representatives?

The layout of the foam room is for reference and to show the intent of the layout. Per the contract drawings, the contractor shall be responsible for providing all necessary clearances and avoiding all conflicts/obstructions.

31. The foam tank shown on the foam/fire pump room detail on Sheet FX401 appears to be wider than the door. Has the Fire Protection Engineer of Record confirmed that the required foam concentrate tank will fit through the doors without having to perform architectural modifications?

The contractor shall provide a foam tank that will fit through the existing opening.

32. Has the Fire Protection Engineer of Record performed the surge analysis as referenced in Section 3-6.5.1 of UFC 4-211-01 to determine is a surge tank is required and if the 35 gallon tank as shown on the drawings is of adequate size? Specification 21 13 25, Section

3.1.3 references a 25 gallon surge arrestor. Please provide the required size of surge arrestor to be provided if required per the analysis. If a 100 gallon tank is required, there may not be enough space in the room to accommodate it.

The contractor shall provide a surge tank in accordance with Section 21 13 25. The surge tank shall be sized via calculations provided by the surge tank manufacturer.

33. Are revised battery or voltage drop calculations required to be provided for the existing building fire alarm panel as a result of monitoring the new RSFACU, fire pump and other equipment?

Based on the limited work associated with the fire alarm system, revised battery and voltage drop calculations are not required unless the contractor’s fire protection specialist determines that calculations should be provided.

34. Does the existing Monaco transmitter have enough capacity to accommodate any new required monitoring point needed for the RSFACU, or will a new transmitter or additional cards be required?

Contractor shall verify and provide any required expansion cards per section 28 31 76.

35. The life safety plans identify many fire barriers. Is any new walls, or upgrades/fire-stopping work required to be performed on the fire barriers as part of this contract?

Contractor shall properly seal all penetrations through fire barriers (and any other barrier) resulting from the installation of the new foam and foam releasing systems as well as any penetration resulting from any modifications to the existing sprinkler and fire alarm systems as required by Sections 21 13 13.00 10, 21 13 25 and 28 31 76.

36. How much of the existing water supply piping and existing wet pipe sprinkler system piping is to remain in the foam/fire pump room?

All existing foam system components and piping shall be replaced as noted on the Contract Drawings.

37. Who is the Designated Fire Protection Engineer for the project as referenced by UFC 3- 600-01?

The Air National Guard Fire Protection Engineer or their designated representative.

38. Who is the fire protection Authority Having Jurisdiction for the project?

The Little Rock Air Force Base (19CES) Fire Department and the Air National Guard Fire Protection Engineer

39. Is there a minimum number of construction site inspections expected to be performed by the Fire Protection Specialist / Qualified Fire Protection Engineer for the project?

Per Section 21 13 25, Paragraph 3.18, the Fire Protection Specialist / Qualified Fire Protection Engineer is required to inspect the system periodically during the installation to assure the system is being provided and installed in accordance with the contract requirements. The Air National Guard Fire Protection Engineer should respond as to the approximate number of inspections they anticipate.

40. Is the Fire Protection Specialist / Qualified Fire Protection Engineer expected to review and approve the UL Listed Firestop Assemblies and to perform inspections of any fire-stopping performed as outlined in Specification 07 84 00?

Yes.

41. Since the fire protection specialist is only to apply their “review stamp”, does this infer that the fire protection engineer of record will remain as the engineer or record of designer of record for the project? In summary, who will have the final responsibility and liability for the overall system design, installation, testing and operation of the system?

The contractor’s fire protection specialist shall be responsible for the overall system design, installation, testing and operation of the system per section 21 13 25.

42. Drawing E-101 (New Pump Feeders) There is a large amount of concrete sidewalk and a concrete driveway that will need to be removed and replaced. Could you please provide concrete specifications and details?

The intent is to route the conduit in grassy area to the extent possible minimizing impact to existing sidewalk. The Keynote-3 on E-101 shall be replaced to read “DIRECT

BURIED CONDUIT WITH FIRE PUMP FEEDER. REFER TO RISER DIAGRAM FOR

SIZING. DEMOLISH AND REMOVE EXISTING SIDEWALK AND PAVEMENT IN

AREA OF INSTALLATION BY OPEN CUT MINIMUM 2-FT WIDE. SAWCUT

CONCRETE FULL DEPTH AT TRENCH LOCATION. SIDEWALK REPLACEMENT

SHALL CONSIST OF 4” OF CONCRETE OVER 4” OF AGGREGATE BASE.

PAVEMENT REPLACEMENT SHALL CONSIST OF 8” CONCRETE OVER 4”

AGGEGATE BASE, MATCH EXISTING. CONCRETE SHALL BE 4,000 PSI. COMPACT

SUBGRADE TO 95% PER ASTM D-1557 PRIOR TO CONCRETE PLACEMENT. IN

GRASSY AREA REMOVE AND SET SOD ASIDE BEFORE DIGGING AND REPLACE

ONCE CONDUIT HAS BEEN PLACED AND BURIED. BURIAL DEPTH TO BE 24

INCHES MINIMUM.

43. Please verify that no interior work can be performed from 15 April to 31 August? This typically only applies to exterior/roofing work.

Interior work can be performed from 0700-1700 M-F with the exception of Federal Holidays. Please also note that work schedule may be impacted by base, local, state, or Federal restrictions related to the COVID-19 pandemic.

44. Is there an Asbestos Survey available?

Yes – see Attachment E (BLDG 207 Hazardous Materials Survey). This survey was completed in December 2018 as part of the design work for this project.

45. Division 21 and Division 28 require the fire protection specialist to be the same individual. Is the government’s intent for this person to be contracted directly to the general contractor? Or, is it acceptable for each subcontractor to separately retain the same fire protection specialist?

While it is preferred for the GC to contract directly with the fire protection specialist, it is not required provided the same fire protection specialist is enlisted by all subcontractors for all fire protection work.

46. Please indicate the electrically classified areas within the building. It is expected that all new fire alarm equipment and conduit will be greater than 18 inches above finished floor, but it is common to install equipment such as battery boxes and some auxiliary panels within the 18-inch zone.

All equipment should be installed at least 18 inches above the finished floor. If this is not possible, then the equipment (or equipment enclosures) shall be NEMA 8 rated at a minimum.

47. The foam equipment room layout on RFP sheet FX401 does not provide the 3 foot clearance path to all equipment required by UFC 3-600-01 9-5.1.5. Please confirm UFC 3-600-01 required clearance is not required. Note that it appears compliance with this criteria would require a larger foam equipment room.

The layout of the foam room is for reference and to show the intent of the layout. Per the contract drawings, the contractor shall be responsible for providing all necessary clearances and avoiding all conflicts/obstructions.

48. RFP Specification 21 30 00 paragraph 2.2 requires the fire pump to be rated at 90 psi @ 1500 gpm, but RFP drawing FX401 requires the fire pump to be rated at 80 psi @ 1500 gpm. Please confirm which is correct.

The contractor shall size the fire pump based on their hydraulic calculations.

49. RFP Specification 21 30 00 does not require the fire pump controller to be provided with an automatic transfer switch and the foam room only allocates about 2’2” of width for the fire pump controller which suggests the room was not designed around a controller with ATS. Please confirm the power supply has been determined to be reliable and that the controller does not require an ATS.

An automatic transfer switch is not required as the building is not provided with an emergency generator.

50. While not technically a series fire pump arrangement per NFPA 20, it is important for the upstream fire pumps to operate relatively quickly to ensure the hangar fire pump does not create a low NPSH scenario. In coordination with NFPA on previous campus style fire pump configurations, it has been recommended to consider the inclusion of some of the series fire pump features (such as remote start and/or interlock) to mitigate some of the risk of the pseudo-series pump configuration. The RFP does not indicate any series fire pump features; please confirm the hangar and upstream fire pumps are not required to comply with any of the series fire pump configuration criteria of NFPA 20.

The new fire pump is not required to meet the requirements of pumps in series outlined in

NFPA 20.

51. RFP Specification 21 13 25 paragraph 3.1.3 requires surge tank sizing calculations to be performed by the surge tank manufacturer to validate the size of the surge tank. RFP Drawing FX401 indicates a surge tank capacity of 35 gallons (minimum). Given the size and configuration of the foam room, a large surge tank may not fit. Please confirm whether a single 35 gallon surge tank is acceptable where indicated on FX401 or clarify if the contractor is responsible for obtaining surge tank sizing calculations. Given the relative complexity of campus style fire pumps and their impact on surge tank sizing, if the government’s intent is for the contractor to obtain surge tank manufacturer’s calculations, please provide all variables which must be used to solicit these surge tank calculations (pressure wave speed, pipe size, design flow rate, etc.).

The contractor shall provide a surge tank in accordance with Section 21 13 25. The surge tank shall be sized via calculation provided by the surge tank manufacturer.

52. RFP Specification 21 13 25 paragraph 1.3.7 suggests the working pressure of the fire water distribution system is well over 125 psi. Even at the rated pressure of the hangar pump, the downstream working pressure inside the foam room will exceed 175 psi. This can have multiple impacts from sourcing strainers, surge tanks, and flow control valves to modified fire pump dimensions, flange bolt patterns, and associated coordination. Since there is not room in the foam room for a pressure reducing valve and since the RFP does not specify a variable speed pressure limiting fire pump controller, it appears the intent of the government is to specify high pressure components downstream of the hangar pump.

Please confirm the pressure downstream of the hangar pump is expected to exceed 175 psi.

The contractor shall provide equipment downstream of the new fire pump based on their hydraulic calculations. Where pressures exceed 175 psi, high pressure rated equipment shall be provided.

53. RFP Specification 21 13 25 paragraph 1.3.7 describes three separate existing fire pump stations which feed the existing fire water distribution system which will supply the new fire pump and existing wet pipe sprinkler systems. Please confirm 1) all of the existing pumps are in parallel 2) the pump starting pressures/sequence and 3) the water supply curve which must serve as the basis of supply calculations and demand calculations (may not be identical). It is acknowledged that the RFP requires calculations to be based “on the operation of the minimum number of pumps running necessary to supply the high-expansion generators and the sprinkler design area.” However, if the calculations are based on the minimum number of pump necessary, this may under predict the supply calculations required by 1.3.7.a. It is not practical to predict the water supply curve of a large parallel pumping system such as this without a flow test which simulates the hangar calculation flow rate due to unpredictability in exact pump start sequence when multiple parallel pumps are provided with different start pressures.

The exact starting process of the existing fire pump system will need to be provided by Base CE to ensure accuracy.

54. RFP Specification 21 13 25 paragraph 3.23.1 requires simulation of overhead sprinkler system demand. Overhead sprinkler system demand simulation is not required by UFC 4- 211-01 for Air Force hangars and also is automatically tailored out by most recent versions of UFGS (21 13 25). Please confirm whether overhead sprinkler system flow rate and hose demand must be simulated during the various required foam system tests.

Based on discussions with the AFCEC Fire Protection Engineer and their designated representatives, simulating the sprinkler flow during testing of the high expansion foam system is no longer required when the foam system utilizes the inductor proportioning method.