Attachment_6_-_LPS_Design_Checklist.pdf

Facility/Project Name/Number: Date:

Design Evaluator Name:

SECTION 6: Lightning Protection Systems (LPS) Design and Inspection This checklist is extracted from AFMAN 91-210: Explosives Safety Standards, dated 1/12/11; AFI 32-1065: Grounding Systems, dated 2/3/03 and AFSPC Supplement 1, dated 10/1/09; AFI32-1065: Grounding Systems, AFSPC Supplement 1, dated 2/3/03; NFPA 780: Standard for the Installation of Lightning Protection Systems, 2011 Edition; and Lightning Protection for Engineers (ISBN 0-9759001-0-2), updated 1/11. Additionally, AFSPC MAN91-710, Volume 5, Para 5.1.4.1 was consulted for the development of this checklist.

EVALUATOR/INSPECTOR NOTES

(1) All references are to NFPA 780, 2011 Edition unless otherwise indicated. (2) LPS means Lightning Protection System.

(3) SPD means Surge Protective Device. (4) In NFPA 780, all asterisks (*) refer to NFPA 780, Annex A (Explanatory Material). NOTE: For the purposes of this checklist, asterisks should be treated as mandatory requirements. (5) Explain any checklist items marked “NO.” (6) Make any evaluator/inspector comments in the specific step block and/or use the Remarks section at the end of the checklist.

SECTION 6A: DESIGN

General. Design and installation of a LPS must meet, at a minimum, the requirements of AFI 32-1065, Grounding Systems and NFPA 780, Chapter 8. The LPS must feature air terminals, down conductors, sideflash protection, surge suppression of data lines and bonding of all other conductive penetrations into the protected area, and earth electrode systems. Structural elements of the building may serve as air terminals, down conductors, or the earth electrode. The LPS must be designed to intercept lightning at a 100 ft or less striking distance arc in accordance with NFPA 780 NOTE: The pitched roof requirements of NFPA 780 may not be used in lieu of this requirement. (AFMAN 91-201, Para 5.23.) NOTE: Throughout the design process, Range Users are encouraged to consult with-30 SW/SEAL and 30 SW/SEW on LPS design issues.

YES NO N/A

6A.1 Is the facility located at or near the airfield? NOTE: If there is a conflict between NFPA 780, Chapter 8 requirements and airfield or flightline operation requirements, the airfield/flightline requirements take precedence. Contact 30 SW Airfield Operations if there are any questions.

(NFPA 780, Section 8.1.2)

Waivers/Exemptions

Attachment 6 2 Feb 17

6A.2 Do all of the following apply? (Section 8.1.3)

Facility has lightning warning system notifying personnel of lightning within 10 nautical miles and operations are then terminated.

All personnel evacuated from the facility.

Resulting damage and loss from a lightning strike are acceptable to 30 SW/CC, 30 SW/SEAL

30 SW/SEW, 30 CES/DEF, and program manager.

Personnel are not expected to sustain injury; a minimal economic loss to the structure, its contents, or surrounding facilities; and the resulting damage and loss from a lightning strike are acceptable to 30 SW/CC, 30 SW/SEW, and 30 CES/DEF.

If “YES,” to all of the above, LPS is not required by NFPA 780; however, coordination with 30 SW/SEW/SEAL is still required to ensure AFMAN 91-201 and AFSPCMAN 91-710 requirements are fulfilled.

General Explosives Requirements 6A.3 Is the LPS design based upon a Striking Distance of 30 m (100 ft)? (Sections 8.2.1 & 7.3.2)

NOTE: The key concepts throughout the design are Striking Distance and Zone of Protection.

Striking Distance is defined as the distance over which the final breakdown of the initial lightning stroke to ground or to a grounded object occurs. The Zone of Protection refers to the space adjacent to a LPS that is substantially immune to direct lightning flashes (does not refer to personnel).

6A.4 If electromagnetic coupling is a concern, does the design require a mast or catenary system?

NOTE: Mast or catenary systems mandatory when electromagnetic coupling is an issue. (Section 8.2.2) NOTE: Coupling exists between circuits when they are mutually affected by the same electromagnetic field.

Explosives Location LPS 6A.5 Is the LPS a :

metallic (Faraday-like) cage, single or multiple masts, an overhead wire (catenary) system, and/or an integral system (Franklin rods)?

NOTE: A Faraday cage provides optimum protection. See Section 8.3.1.

6A.6 Does the single or multiple mast LPS having a striking distance of 30 m (100 ft) radius? (Section 8.3.2)

6A.7 Is the mast or masts “remote” from the structure under protection? (Section 8.3.2.1) 6A.8 If metallic masts are used, are they at least 16 mm (5/8 in) in diameter? (Section 8.3.2.1.1) 6A.9 For nonmetallic masts, is the strike termination device (e.g., Franklin rod) or metal cap have a minimum thickness of 4.8 mm (3/16 in) and connected to ground by at least one down conductor?

(Section 8.3.2.1.2)

6A.10 For nonmetallic masts using a pole guy wire as a down connector, is the guy wire a continuous metal cable without any ceramic or insulating sections? (Section 8.3.2.1.3)

6A.11 For all masts with metallic guy cables (normal practice), is the cable bonded at its lower end to the grounding electrode (e.g., counterpoise)? (Section 8.3.2.1.4)

Overhead Wire/Catenary System 6A.12 If a catenary system is used, is the strike distance 30 m (100 ft) radius? (Section 8.3.3) 6A.13 Is the overhead ground wire material:

aluminum, copper, stainless steel, galvanized steel, protected steel such as copper-clad, aluminum-clad, or aluminum conductor steel reinforced (ACSR)?

NOTE: The overhead ground wire material “shall” be chosen to minimize corrosion. (Section 4.6.4.2 & 4.6.4.3)

6A.14 Is the overhead ground wire sized as the same cross-sectional area as the main lightning conductor? The ground wire size (overhead and main) for this project is:

(Section 4.6.4.4) NOTE: Each wire must be a continuous run of at least AWG No. 6 copper, or equivalent. (AFI 32- 1065, Para A4.2.2) NOTE: The lesser AWG rating means the wire is thicker. For example, AWG No. 6 is approximately 4.115 mm (0.1620 in) diameter while AWG No. 2 is approximately 6.544 mm (0.2576 in) diameter.

6A.15 Is the overhead ground wire self-supporting, minimum sag under all conditions, and at least six feet above the structure? (Section 4.6.4.4 and AFI 32-1065, Figure A4.1.)

NOTE: Each wire must be a continuous run of at least AWG No. 6 copper, or equivalent. (AFI 32-1065, Para A4.2.2)

Figure A4.1. Air Terminals on Masts (Typical).

Air Terminals NOTE: Air Terminals (General). An air terminal is a component of an LPS that is able to safely intercept lightning strikes. Air terminals may include overhead wires or grids, vertical spikes, or a building’s grounded structural elements. Air terminals must be capable of safely conducting the current from a lighting strike. (AFMAN 91-201, Section 5.23.1)

6A.16 Are the tips of the air terminals (e.g., Franklin rods) at least 254 mm (10 in) above the object or area the terminals are protecting? (NFPA 780, Figure 4.6.2.1)

NOTE: For non-metallic masts, this is 10 inches above the top of each mast. For facilities and other locations, air terminals must be at least 10 inches above any roof structure, such as roof vents, roof parapet walls, etc. (Section 4.6.2.1)

6A.17 Are air terminals secured against overturning or displacement by one of the following methods?

Attached to the object (e.g., mast, roof, roof vent) to be protected.

Braces that are permanently and rigidly attached to the structure.

(Section 4.6.2.2.1)

6A.18 For air terminals exceeding 600 mm (24 in) in height, are they supported at a point not less than one-half their height, as depicted in Figure 4.6.2.2.2? (Section 4.6.2.2.2)

6A.19 If an integral system (Franklin rods) is used, are the bonding connections and conductor splices free of paint? (NOTE: Painting is not permitted!) (Section 8.3.5)

6A.20 Are the Franklin rods made of:

copper alloy NOTE: Shall be as corrosion resistant as copper. (Section 4.2.2.2), or aluminum? NOTE: Aluminum shall not be used if contact with the earth is possible or “rapid deterioration” is possible. See Section 4.2.2.3.1 NOTE: When used, aluminum conductors shall be of electrical-grade and must be protected against the corrosive salt-air conditions (fog) at VAFB. See Section 4.2.2.3.2. (Section 4.2.2)

Sideflash Distance

NOTE: Sideflash refers to an electrical spark, caused by differences of potential that occurs between conductive metal bodies or between conductive metal bodies and a component of a LPS or ground. (Section 3.3.27) NOTE: Sideflash Protection (General). Protection from side flash is obtained either by bonding metallic objects to the down conductors or the earth electrode system, in accordance with NFPA 780, except as modified herein, or it is obtained by maintaining a separation distance between metallic objects and these LPS components. (AFMAN 91-201, Section 5.23.3) 6A.21 Does the design contain the following calculations for the sideflash distances from the masts?

D=h/6 D: Sideflash distance from mast.

H: structure height (not the height of the mast) (Section 4.6.5.1)

6A.22 Does the design contain the following calculations for overhead ground wires?

(Section 4.6.5.2)

Zones of Protection and Roof Strike Termination Devices NOTE: Zone of Protection is defined as “The space adjacent to a lightning protection system that is substantially immune to direct lightning flashes.” (Section 3.3.39) However, this does not apply to people. NOTE: The geometry of a facility/structure/building determines the Zone of Protection. (Section 4.7) NOTE: One or more Zones of Protection methods may be used. They are by roof type (Section 7.7.2), multiple-level roofs (Section 4.7.3), and or rolling sphere method (Section 4.7.4).

6A.23 For the project, identify below the appropriate roof type.

Pitched roofs.

Flat or gently sloping roofs.

Dormers. (NOTE: A structural element of a building that protrudes from the plane of a sloping roof surface.)

Domed roofs.

Roofs with ridges, wells, chimneys, or vents.

6A.24 For structures with multiple-level roofs and no more than 7.6 m (25 ft) above earth, are the requirements (as applicable) of Figure 4.7.3.3(a) fulfilled? (Section 4.7.3.3) NOTE: AFMAN 91-201 does not permit pitched roof requirements of NFPA 780 (Sections 4.7.1 through 4.7.3.4) to be used to determine the Zone of Protection for explosive structures/facilities.

See Figure 4.8.2.

NOTE: The Zone of Protection shall be delineated by a cone (Rolling Sphere) with the apex located at the highest point of the strike termination device, with its surface formed a 45-degree or 63-degree angle from the vertical, based on the height of the strike termination device above the grounded as depicted in the above figures. (Section 4.7.3.2)

6A.25 For structures with multiple-level roofs that do not exceed 15 m (50 ft) above earth, do they protect lower portions of the structure within a one-to-one zone of protection as shown in Figure 4.7.3.4(a)? (Section 4.7.3.4) NOTE: AFMAN 91-201 does not permit pitched roof requirements of NFPA 780 (Sections 4.7.1 through 4.7.3.4) to be used to determine the Zone of Protection for explosive structures/facilities.

See Figure 4.8.2.

NOTE: The Zone of Protection shall be delineated by a cone (Rolling Sphere) with the apex located at the highest point of the strike termination device, with its surface formed a 45-degree or 63-degree angle from the vertical, based on the height of the strike termination device above the grounded as depicted in the above figures. (Section 4.7.3.2)

6A.26 Using the rolling sphere method to provide the Zone of Protection, does it comply with Figure 4.7.4.1? (Section 4.7.4.1) NOTE: AFMAN91-201, Para 14.25.2.2 encourages submittal of rolling sphere drawings similar to Figure 4.7.4.1.

NOTE: Striking distance is 30 m (100 ft).

NOTE: Where the sphere is tangent to earth and resting against a strike termination device, all space in the vertical plane between the two points of contact and under the sphere shall be considered protected. (Section 4.7.4.1.1) NOTE: A Zone of Protection shall also be formed where such a sphere is resting on two or more strike termination devices and shall include the space in the vertical plan under the sphere and between those devices, as shown in Figure

4.7.4.1 (Section 4.7.4.1.2) NOTE: All possible placement of the sphere shall be considered when determining the overall Zone of Protection using the rolling sphere method. (Section 4.7.4.1.3)

6A.27 In all instances, are LPS systems designed to protect structures housing explosives based on a striking distance of 30 m (100 ft), as discussed in Section 7.3.2? (Section 8.2.1)

NOTE: For explosive structures exceeding the striking distance (30 m or 100 ft) above earth or above a lower strike termination device, the Zone of Protection shall be the space in the vertical plan between the point of contact, and also under the sphere where the sphere is resting against a vertical surface of the structure and the lower strike termination device(s) or earth. Additionally, the sides of tall structures, e.g., mobile service towers (MST), are subject to direct lightning strikes.

(Section 4.7.4.2)

6A.28 If the design involves a tall structure such as a MST and the decision is made not to protect the sides of the structure, is a Lightning Risk Assessment produced IAW NFPA 780, Annex K (or similar acceptable risk assessment such as AFMAN 91-201, Chapter 4)? (Section A.4.7.4.2) NOTE: If such an assessment is provided, review and comment on that assessment.

6A.29 When masts and overhead ground wires are used, does the design comply with Sections 8.2.1, 7.3.2.2, 7.3.2.3, 7.3.2.4 and Figure 7.3.2.2 and Figure 7.3.2.4, as appropriate?

NOTE: Striking distance is 30 m (100 ft).

NOTE: Verify the Section 7.3.2.4 formula is correctly applied, if used.

6A.30 Are the strike termination devices (Franklin rods) designed and installed IAW Section 4.8.1 through Section 4.8.1.2 and Figure 4.8.1?

6A.31 For pitched roofs with eave heights over 15 m (50 ft) but less than 30 (m) (100 ft) above grade, are the strike termination devices designed and installed IAW Section 4.8.2 through Section

4.8.2.3 and Figure 4.8.2?

NOTE: Remember, the strike termination distance for explosives locations is 30 m (100 ft).

30 m (100 ft)

6A.32 For flat or gently sloping roofs that exceed (15 m) in width or length, are one of the following requirements fulfilled? NOTE: Check the blocks that apply.

Have additional strike termination devices located at intervals not to exceed 15 m (50 ft) on the flat or gently sloping areas, as shown in Figures 4.8.3(a) and 4.8.3(b), or, The areas can also be protected by using taller strike termination devices that create Zones of Protection using the Rolling Sphere method so the sphere does not contact the flat or gently sloping roof area? (Section 4.8.3)

30 m (100 ft)

6A.33 For dormers, are the requirements of Section 4.8.4 through 4.8.4.2 and Figure A.4.8.4 (see below) fulfilled?

D Dormer

6A.34 For flat or gently sloping roofs with irregular perimeters, are the requirements of Section 4.8.6 through Section 4.8.6.5 and Figure 4.8.6.2 and Figure 4.8.6.5 fulfilled? NOTE: These types of roofs are treated individually to ensure an adequate Zone of Protection.

6A.35 For open areas in flat roofs where the open area perimeter exceeds 92 m (300 ft) and both rectangular dimensions exceed 15 m (50 ft), is the open area perimeter protected? (Section 4.8.7)

6A.36 For domed or rounded roofs, are the strike termination devices situated so that no portion of structure is located outside the Zone of Protection as required in Section 4.7? (Section 4.8.7)

6A.37 In cases of chimneys and vents, are the requirements of Section 4.8.9 through Section 4.8.9.4 and Figure 4.8.9.3 fulfilled?

6A.38 In cases involving metal roof top units, are the following requirements fulfilled? NOTE: Metal roof top units include continuous metal housings less than 4.8 mm (3/16 in) thick such as air-conditioning/heating units, metal air intake/exhaust housings, and cooling towers that are not located within the Zone of Protection. (Section 4.8.10)

a. Are air terminals (Franklin rods) installed in accordance with NFPA 780, Sections 4.8.1 through 4.8.3? (Section 4.8.10.1)

b. Are the Franklin rods mounted on bases having a minimum contact area of 1940 mm2 (3 in2), each secured to the bare metal of the housing or mounted by drilling and tapping to the unit’s frame IAW Sections 4.16.3.2 and 4.16.3.3? (Section 4.8.10.2)

c. Are at least two main-size conductors installed to connect the roof unit to the LPS (e.g., down conductor)? (Section 4.8.10.3)

d. Are the connections to the bare metal of the unit at the base or lower edges of the unit using main-size conductors and bonding devices that have a surface contact area of not less than 1940 mm2 (3 in2) and provide two or more paths to ground, as required for strike termination devices? (Section 4.8.10.3.1)

e. Are the two main bonding plates located as far apart as practicable at the base or lowered edges of the roof unit’s electrically continuous metal housing and connected to the LPS?

(Section 4.8.10.3.2)

Conductors NOTE: The three type of conductors are:

1. Bonding conductors are a conductor used for potential equalization between grounded metal bodies or electrically conductive object and a LPS.

2. Loop conductors are a conductor encircling a structure that is used to interconnect grounding electrodes, main conductors, or other electrically conductive bodies.

3. Main conductors are a conductor intended to be used to carry lightning currents between strike termination devices and grounding electrodes. Main conductors also serve as strike termination devices for catenary LPS.

(Section 3.3.7) 6A.39 Do main conductors:

Interconnect all strike termination devices, and All conductors form two or more paths from each strike termination devices downward, horizontally, or rising at no more than ¼ slope to connection with grounding electrodes?

(Section 4.9)

6A.40 If there are exceptions to the above main conductor requirement, do they fulfill both of the following requirements of NFPA 780?

Section 4.9.1 (One-Way Path), and Section 4.9.2 (Dead Ends).

6A.41 Concerning the substitution of main conductors, are the following requirements fulfilled?

a. Are ancillary metal parts of a structure (e.g., eave troughs, downspouts, ladders, chutes, or other metal parts) prohibited from serving as main conductors? (NOTE: The one exception is found in Section 4.16.1, i.e., metal framework of a structure.) (Section 4.9.3.1)

b. In cases of permanent exterior metal handrails and ladders that are subject to direct lightning strikes (e.g., on roof or between roofs) and are electrically continuous, is the minimum thickness of the handrails and ladders 1.63 mm (0.064 in)? (Section 4.9.3.2)

c. If metal roofing or siding is to serve as a main conductor, is the roofing and/or siding equal to or greater than 4.8 mm (3/16 in) in thickness? (Section 4.9.3.3)

6A.42 Do conductors maintain a horizontal or downward course, free from "U" or "V" down/up packets?

(Section 4.9.4.1) NOTE: In cases where such pockets exist (e.g., low-positioned chimneys, dormers, parapet walls, or other projections on sloped roofs), a down conductor from the base of the pocket to ground or to an adjacent downlead conductor is required as depicted in Figure 4.9.4.2.

6A.43 Do all conductor bends form an angle of 90 degrees or greater and is the radius of bend at least 203 mm (8 in), as shown in Figure 4.9.5?

6A.44 For conductors that are coursed through air without support, is the maximum distance 0.9 m (3 ft) or less? (Section 4.9.6.1)

6A.45 For conductors that must be coursed through air at greater than 0.9 m (3 ft), are the conductors supported in such a manner to prevent damage or displacement of the conductors?

(Section 4.9.6.2)

6A.46 Are roof conductors coursed as described/required below to ensure interconnection of all strike termination devices?

Ridges of cable, gambrel, and hip roofs.

Around the perimeter of flat roofs.

Behind or on top of parapets.

Across flat or gently sloping roofs.

(Section 4.9.7.1)

6A.47 Are conductors coursed through or around obstructions (e.g., cupolas and ventilators) in a horizontal plane with the main conductor? NOTE: A cupola is a light structure or a dome on a roof.

It also refers to a "domelike" structure. (Section 4.9.7.2)

6A.48 For flat or gently sloping roofs that exceed 15 m (50 ft) in width, do cross-run conductors (main conductors) interconnect the strike termination devices? NOTE: For example, roofs from 15 m to 30 m (50 ft to 100 ft) in width shall have one cross-run conductor. Roofs 30 m to 46 m (100 ft to 150 ft) in width are required two cross-run conductors, and so on. (Section 4.9.8 and Section 4.9.8.1)

6A.49 Are cross-run conductors connected to the main perimeter cable at intervals not exceeding 30 m (100 ft), as shown in Figure 4.8.3(a)? (Section 4.9.8.2)

6A.50 The following are specific down conductor requirements. NOTE: Down conductors (flat or round) provide low impedance paths from the air terminals described above to the earth electrode (ground) system. Structural elements having a high current capacity and a low impedance to ground need not be augmented with wires. Where wires are used as down conductors, these shall meet the requirements of NFPA 780. See AFMAN 91-201, Section 5.23.2.

a. Are down conductors as widely separated as practicable? (Section 4.9.9.1)

30 m (100 ft)

b. Identify all the below considerations that were used in the design of this LPS.

Placement of strike termination devices.

Most direct coursing of conductors.

Earth conditions.

Security against displacement.

Location of large metallic bodies.

Location of underground metallic piping systems. (Section 4.9.9.2)

NOTE: An underground storage site requires protection against lightning only for exposed or partially exposed parts. Lightning protection requirements will be considered on a site specific basis. (AFMAN 91-201, Section 5.23.7)

c. Are there at least two down conductors on each structure, regardless of the type of structure?

(Section 4.9.10)

d. For structures exceeding 76 m (250 ft) in perimeter, do they have a down conductor every 30 m (100 ft) of perimeter or fraction thereof? (Section 4.9.10.1)

e. For flat or gently sloping roofs, is the average distance between all down conductors 30 m (100

ft) or less? (Section 4.9.10.2) NOTE: For these roofs, only the perimeter of the roof areas requiring protection shall be measured. See Section 4.9.10.4. NOTE: Lower roofs or projections that are located within a Zone of Protection are not required to be included in the perimeter measurement. (Section 4.9.10.6)

f. If there are irregular structures, are there additional down conductors to provide a two-way path from each strike termination device? (Section 4.9.10.3)

g. For pitched roofs, is the horizontal projection (footprint) of the protected roof measure as shown in Figure 4.9.10.5? (Section 4.9.10.5)

NOTE: Lower roofs or projections that are located within a Zone of Protection are not required to be included in the perimeter measurement. (Section 4.9.10.6)

6A.51 The following concern the protection of down conductors.

a. Are down conductors guarded that are located in runways, driveways, walkways, or other locations subject to physical damage or displacement? (Section 4.9.11)

b. If metallic guards are used, are they bonded at each end? (Section 4.9.11.1)

c. Are down conductors protected for a minimum distance of 1.8 m (6 ft) above grade? (Section

4.9.11.2) NOTE: Generally, ABS serves this function well.

d. Is the soil less than 10,000 ohm centimeters resistivity? NOTE: If the answer is “YES,” the down conductors must be protected against corrosion by a protective covering beginning at a point 0.9 m (3 ft) above grade level and extending the entire length below grade (to a ground rod or ground loop conductor). (Section 4.9.12) (AFI 32-1065, Para A4.1.14)

6A.52 The following concern down conductors and structural columns. (Section 4.9.13)

a. Are the down conductors connected to the reinforcing steel or the structural steel member at their upper and lower extremities? (Section 4.9.13)

b. For structures with metallic columns that serve as down conductors, do the columns average

18.3 meters (60 feet) or less apart? (AFI 32-1065, Para A4.1.6)

c. In case of long vertical members, is there an additional connection at intervals not exceeding 60 m (200 ft)? (Section 4.9.13.1) NOTE: Connections shall be listed clamps, listed bonding plates, or by welding or brazing. “Listing” refers to recognized organizations, e.g., the International Association of Plumbing and Mechanical Officials (IAPMO), that evaluates products and services to ensure those products and services meet appropriate design and manufacturing standards. See Section 4.9.13.2.

d. Are the bonding requirements of Section 4.9.13.1 and 4.9.13.2 satisfied? If “NO,” list below the design provisions that ensure the required interconnection of the parallel vertical paths.

(Section 4.9.13.3) Those design provisions are:

NOTE: The use of PVC conduit or other nonmetallic chase shall not eliminate the need to stratify the bonding requirements of Sections 4.19, 4.20, and 4.21. (Section 4.9.14)

Conductor Fasteners 6A.53 Are conductors fastened to the structure upon which they are placed at intervals not exceeding

0.9 m (3 ft)? (Section 4.10)

6A.54 Are fasteners (e.g., nails, screws, bolts, or adhesives) not subject to breakage and of the same material as the conductor or a material equally resistant to corrosion as the conductor? (Section 4.10.1)

6A.55 Do all fasteners, regardless of the material or configuration, prohibit corrosion acceleration?

(Section 4.10.2)

6A.56 Where masonry anchors are used to attach LPS materials, is the minimum outside diameter of the anchor 6.4 mm (1/4 in)? (Section 4.11)

6A.57 Are the holes drilled to receive the anchors located in the brick, stone, or other masonry unit other than the mortar joints? (Section 4.11.1)

6A.58 Where the anchors are installed, is there a tight fit against moisture to retard the possibility of damage due to freezing? (Section 4.11.2) (NOTE: Not a major concern for VAFB; however, freezing temperatures are possible.)

6A.59 Are connector fittings used at all “end-to-end,” “tee,” or “Y” splices of conductors? (Section 4.12) 6A.60 Are all fittings so attached to withstand at least 890 N (200 lb) pull test? (Section 4.12.1) 6A.61 Are fittings used for required connections to metal bodies or structures secured by bolting, brazing, welding, or high-compression connectors listed for this purpose? (Section 4.12.2)

6A.62 Are conductor connections bolted, welded, high compression, or crimp type? (Section 4.12.3) NOTE: Cadmium weld preferred. NOTE: “Crimp-type connections shall not be used with Class II conductors.” (Section 4.12.4) Class II conductors are required for buildings above 75 feet.

(Section 3.3.26.2)

6A.63 Where appropriate, are the minimum Class I material requirements for structures under 75 ft fulfilled IAW Table 4.1.1.1.1?

6A.64 Where appropriate, are the minimum Class II material requirements for structures above 75 ft fulfilled IAW Table 4.1.1.1.2?

Grounding of Masts

6A.65 Are metallic masts grounded IAW Figure 8.3.2.2.2? (Section 8.3.2.2.2)

6A.66 Is each down conductor (mast) terminated at a ground ring conductor dedicated to the LPS?

NOTE: See the two exceptions described in Section 8.4.1. (Section 4.13.1.1 and Section 8.4.1)

Grounding 6A.67 Is a ground ring conductor (counterpoise) used with all down conductors, structural steel, ground rods, and other grounding systems connected to the counterpoise? NOTE: Exception #1:

Counterpoise is not required for structures with areas of 46.5 m2 (500 ft2) or less or those structures that can be protected by a single mast or air terminal (e.g., Franklin rod). Exception #2:

Counterpoise is not required for portable structures meeting the provisions of Section 8.6.5 (metal portable magazines. (Section 8.4.1)

6A.68 If concrete-encased electrodes (“concrete footing”) are used, is there compliance with the following requirements? (Section 8.4.2) NOTE: Concrete-encased electrode also referred to as a “Ufer” ground.

a. Only used in new construction? (Section 4.13.3)

b. Is the electrode encased in at least 50 mm (2 in) of concrete, near the bottom of the concrete/foundation, and in direct contact with the earth? (Section 4.13.4.1)

c. Does the encased electrode consist of one of the following:

not less than 6 m (20 ft) of bare copper main-size conductor, or at least 6 m (20 ft) of one or more steel reinforcing bars or rods not less than 12.7 mm (1/2

in) in diameter that have been effectively bonded together by either welding or overlapping 20 diameters and wire tying? (Section 4.13.3.2)

6A.29 If ground ring electrodes (counterpoises) are used, do they meet the following requirements?

a. Are only Class II, insulated conductors (or better) used? (Section 8.4.3)

b. Are ground loop conductors at least AWG No. 1/0 copper? (AFI 32-1065, Para A4.1.15)

c. Is the ground ring electrode installed IAW Figure 4.13.4? (Section 4.13.4)

d. Are the ground ring electrodes (counterpoise) in direct contact with the earth at a depth of not less than 0.76 m (2.5 ft) or encased in a concrete footing? (AFI32-1065, Para A2.2.2.1.4)

e. Is the counterpoise “main-size,” i.e., designed to carry lightning currents between masts and the grounding electrodes? (Section 4.13.4.2)

f. Are the electrodes augmented with at least two ground rods meeting the requirements of NFPA 780, Section 4.13.2.4? (Section 8.4.3.1) NOTE: Section 4.13.2.4 requires that for multiple connected ground rods, the separation distance between any two ground rods shall be at least the sum of their driven depths, where practicable. If this requirement cannot be fulfilled, state why in the Remarks section below.

g. Is the ground ring electrode installed no less than 0.9 m (3 ft) or more than 2.4 m (8 ft) from the structure foundation or footing? (Section 8.4.3.2 & AFI 32-1065, Ground Loop definition)

6A.30 If radials are used, do they meet the following requirements?

a. Are the radials main-size conductors and are they in separate trenches extended outward from the location of each down conductor? (Section 4.13.5.1)

b. Is each radial electrode at least 3.6 m (12 ft) in length? (Section 4.13.5.2)

c. Are all radial electrodes buried at least 460 mm (118 in) below grade? (Section 4.13.6.2)

6A.31 If ground plate electrodes are used, do they fulfill the following requirements?

a. Does the ground plate or plate electrode have a minimum thickness of 0.8 mm (0.032 inc) and a minimum surface area of 0.18 m2 (2 ft2)? (Section 4.13.6.1)

b. Is the ground plate electrode buried at least 460 mm (18 in) below grade? (Section 4.13.6.2) Ground Rods

6A.32 When used, are ground rods at least 19.05 mm (3/4 in) in diameter and at least 3 m (10 ft) in length? (AFI 32-1065, Para A4.1.11)

6A.33 Are ground rods free of paint or other nonconductive coatings? (Section 4.13.2.2) 6A.34 Do ground rods extend vertically into the earth at least 3.05 m (10 ft)? (Section 4.13.2.3.1) 6A.35 Is the earth compacted and tight against the length of the conductor and ground rod as illustrated in Figure 4.13.2.3.2? (Section 4.13.2.3.2)

NOTE: Ground rods with tops at least

0.31 meters (1 foot) below grade are recommended. (AFI 32-1065, Para A4.1.11)

6A.36 Where multiple ground rods are used, is the separation distance between any two ground rods at least the sum of their driven depths, where practicable? (Section 4.13.2.4) NOTE: There is minimal benefit if the second rod is placed too close to the first. (A.4.13.2.4)

6A.37 Are ground rods copper-clad steel or solid copper? (Section 4.13.2.5) NOTE: AFI 32-1065, Para A2.2.1 prohibits stainless steel ground rods because stainless steel is very susceptible to corrosion in many soil conditions.

Bonding 6A.38 Are the following general bonding requirements fulfilled? (Section 8.5.1)

a. Review Section 4.19.1.1 through Section 4.19.1.4. Do any factors (i.e., sideflash, influence of nongrounded metal body, bonding distance requirements, metal bodies) described in these paragraphs apply? NOTE: These factors determine if bonding is or is not required. NOTE: In the Remarks section, document the results of this review and the reason for bonding or the reason why bonding is not required.

b. Are the horizontal loop conductors used for the interconnection of LPS download conductors, grounding electrodes, or other grounded media sized no smaller than the size required for the main conductors, as listed in Table 4.1.1.1.1 and Table 4.1.1.1.2? (Section 4.19.2.1)

c. Are conductors used for the bonding of grounded metal bodies or isolated metal bodies requiring connection to the LPS sized IAW Table 4.1.1.1.1 and Table 4.1.1.1.2? (Section 4.19.2.2.)

NOTE: The items below concern the bonding of metal bodies. See Section 4.21.

6A.33 Does the facility involve long, vertical metal bodies? If “Yes,” ensure the following requirements are fulfilled.

a. For steel-frame structures with grounded and ungrounded metal bodies exceeding 18 m (60 ft) in vertical length, are they bonded to the structural steel members as near as practicable to their extremities? NOTE: Not required if the metal bodies are inherently bonded through construction at their extremities. (Section 4.21.1.1)

b. In the cases of reinforced concrete structures where the reinforcement is interconnected and ground in accordance with Section 4.15.3 (conductors sealed inside the reinforced concrete), are they bonded to the structural steel members as near as practicable to their extremities?

NOTE: Not required if the metal bodies are inherently bonded through construction at their extremities. (Section 4.21.1.2)

6A.34 Where grounded metal bodies have been connected to the LPS at only one extremity, have one of the following formulas been used to determine if additional bonding is required?

D = h/6n x Km (NOTE: Structures more than 12 m (40 ft) in height. See Section 4.21.2.4.

D = h/6n x Km (NOTE: Structures 12 m (40 ft) and less in height. See Section 4.21.2.5.

NOTE: For 30 SW/SEW reviewer, spot check the calculations to ensure accuracy.

NOTE: The following items pertain to isolated (nongrounded) metallic bodies such as a metal window frame in a nonconducting medium. See Section 4.21.3 for more information.

6A.35 For the determination of the bonding requirements, has the following method been used to determine if bonding is required?

If a + b is less than the calculated bonding distance, then A shall be bonded directly to B.

(Section 4.21.3.1.1)

If a + b is greater than the calculated bonding distance, bond shall not be required.

(Section 4.21.3.1.2)

6A.36 If bonding is required, is the process and formulas described in Section 4.21.2 followed?

(Section 4.21.3.2)

6A.37 If bonding is required, are the bonding connections made between the LPS and the grounded metal body? (Section 4.21.3.3, Section 4.21.3.3.1, & Section 4.21.3.3.2[isolated metal body]))

Fences NOTE: AFMAN 91-201, Section 5.23.3.1 requires metallic fences within six feet (1.9 m) of a structure’s LPS to be bonded to the structure’s LPS. NFPA 780, Section 8.5.5 requires bonding for “metallic fences.”

6A.38 Do metallic fences have bonding across gates as well as other discontinuities and are they bonded to the LPS ground ring electrode? (Section 8.5.5)

6A.39 Is there bonding between the metallic fence and the structure/facility? (Section 8.5.5.1) 6A.40 Are all gateposts grounded to a grounding electrode? (Section 8.5.5.2) 6A.41 Do gateposts have bonding conductors running between them and buried not less than 38 mm

(18 in)? (Section 8.5.5.2.1)

6A.42 Are all gates bonded to grounded gateposts? (Section 8.5.5.2.2) 6A.43 If there are any nonconductive gateposts supporting horizontal single metallic strands, are there down conductors extending the full height of the nonconductive pole and are they bonded to each singe stand to form a continuous path to ground? (Section 8.5.5.2.3)

6A.44 Where nonmetallic-coated fencing is supported by metallic posts, are the posts connected together at their tops by a rigid metallic bar or wire bonded to the support post? (Section 8.5.5.3)

Access Doors 6A.45 Are all metal doors allowing access to the facility/structure bonded to the ground ring electrode?

(Section 8.5.6.1)

6A.46 Are the frames or roll-up or slatted doors bonded to the ground ring electrode? (Section 8.5.6.2) Metallic Barricades or Bollards

6A.47 Does the design involve metallic barricades or bollards? NOTE: If “YES,” refer to Sections 8.5.7 and 4.21.2.4 for design requirements. Record findings in Remarks section below. (Section 8.5.7)

Railroad Tracks 6A.48 Are railroad tracks within 1.9 m (6 ft) of an explosives facility? NOTE: If “YES,” refer to Section

8.5.8 through Section 8.5.9.2 for design requirements. Record findings in Remarks section below.

(NFPA 780, Section 8.5.8 and AFMAN 91-201, Section 5.23.3.1)

Earth-Covered Magazines

NOTE: Earth-covered magazines LPS comply with the requirements of NFPA 780, Chapter 4, except as modified below.

(Section 8.6.1) 6A.49 Are air terminals placed on the headwall, the rear ventilator (if present), and at the perimeter of the magazine roof as required to obtain a 30 m (100 ft) radius Zone of Protection? (Section 8.6.1.1)

6A.50 If tall air terminals are in the center of the magazine headwall and roof (in lieu of perimeter air terminals), is adequate protection provided IAW Section 8.2.1? NOTE: Section 8.2.1 requires a striking distance of 30 m (100 ft) as described in Section 7.3.2. (Section 8.6.1.2)

6A.51 Are the steel doors, door frames, and steel reinforcement bonded to the magazine grounding system? (Section 8.6.1.3)

6A.52 Are the incoming power, data, and communications systems protected by SPD as required by Section 4.18? (Section 8.6.1.4)

Piers and Wharves NOTE: The only pier or wharf at VAFB is at the Boathouse. If a LPS is designed, refer to Section 8.6.2.

Cranes For outdoor cranes attached to the facility (not including mobile cranes), refer to Section 8.6.3. For internal facility cranes, verify the crane is properly bonded. (NOTE: Mobile crane standards are found in ASME B30.5.)

Open Storage Pads 6A.53 Is there a mast or catenary system for the open storage pad? (Section 8.6.4.1) 6A.54 Does either or both of the following conditions exist?

Explosives materials within sideflash distance of cables or masts?

Flammable gases or exposed flammable liquids are present on the pad?

NOTE: If either or both exists, then an additional ground ring conductor shall be installed.

(Section 8.6.4.2)

Metal Portable Magazines NOTE: Metal portable magazines are metallic (Faraday-like) cages as described in Section 8.3.1. (Section 8.6.5) 6A.55 Are metal portable magazines grounded with a main conductor? (Section 8.6.5) 6A.56 Is the magazine of the “box-type” and has 4.8 mm (3/16 in) steel or equivalent where the walls, floor, and roof welded? If “YES,” then the doors shall be bonded across each hinge.

(Section 8.6.5.1)

6A.57 Does the magazine have incoming power, data, and communications systems? If “YES,” SPD protection is required IAW Section 4.18. (Section 8.6.5.2)

Single Portable Magazines 6A.58 Do single portable magazines less than 2.3 m2 (25 ft2), outside dimensions, have two ground rods? (Section 8.6.5.3.1) NOTE: Connections to an existing ground ring electrode are permitted in lieu of ground rods. (Section 8.6.5.3.3)

6A.59 For single portable magazines equal to or greater than 2.3 m2 (25 ft2), are they grounded by using a minimum of two separate ground rods, each placed in a different corner (preferably at opposite corners)? (Section 8.6.5.3.2) NOTE: Connections to an existing ground ring electrode are permitted in lieu of ground rods. (Section 8.6.5.3.3)

Portable Magazine Groups NOTE: “Groups” refer to more than one magazine, not DoD explosive compatibility groups.

NOTE: “All earth connections shall provide resistance to earth that is as low as practical.” (Section 8.6.5.4.5) 6A.60 Does each group have a minimum of two connectors to earth? (Section 8.6.5.4.1) NOTE:

Connections to an existing ground ring electrode are permitted in lieu of ground rods. (Section 8.6.5.4.4)

6A.61 Do any groups exceed 76 m (250 ft) in perimeter? If “YES,” a connection to earth is required for every 30 m (100 ft) of perimeter or fraction thereof to ensure the average distance between all connections to earth does not exceed 30 m (100 ft). (Section 8.6.5.4.2) NOTE: Connections to an existing ground ring electrode are permitted in lieu of ground rods. (Section 8.6.5.4.4)

6A.62 For smaller groups (less than 76 m in perimeter) requiring only two connections to earth, are the connections placed at opposite ends of the group and as far apart as practicable? (Section 8.6.5.4.3) NOTE: Connections to an existing ground ring electrode are permitted in lieu of ground rods. (Section 8.6.5.4.4)

Surge Protection NOTE: Low-pass filters are permitted for added protection on critical electronic loads as permitted by the AHJ (e.g., 30 SW/SEW). (Section 8.7.3) NOTE: Surge protection is allowed for installation at subpanels or branch panels and at the point of utilization (outlet or signal termination; also termed “supplementary protection”). (Section 4.18.2.4) 6A.63 For all power service entrances and incoming connectors, are SPDs installed? (AFMAN 91-201, Section 5.23.5) (Section 4.18.2.1)

6A.64 Does the surge protection include suppression at the entrance to the explosives facility from each wire to ground? (AFMAN 91-201, Section 5.23.5)

6A.65 Are shielded cabling, power cabling, and communication lines buried underground in metal conduit for a minimum of 50 feet before entering the structure? (AFMAN 91-201, Section 5.23.5) (NFPA 780, Section 8.7.1)

6A.66 For all other metallic utility lines and pipes, are they electrically connected to the LPS or the structural steel of the building just before they enter the building? (AFMAN 91-201, Section 5.23.5)

6A.67 Are conduits bonded to the ground ring electrode where they cross? (Section 8.7.2) 6A.68 If an electrical or electronic system conductor leaves a structure to supply another structure and if the conductors or cables run over 30 m (100 ft), are SPDs installed at all points of the exiting facility? (Section 4.18.2.3)

6A.69 If there has been an engineering determination (i.e., “engineering supervision”) that SPDs are not required, is this determination made because the surge threat is negligible, the lines are equivalently protected, and/or where installation compromises safety? If “YES,” provide a written copy of the engineering determination. (Section 4.18.2.5)

6A.70 Are the following electrical power circuit requirements fulfilled? (Section 4.18.3.1)

a. Does the SPD protect against surges produced by a 1.2/50 µs and 8/20 µs combination waveform generator? (Section 4.18.3.1.1)

b. Do SPDs at the service entrance have a nominal discharge current (In) rating of at least 20 kA 8/20 µs per phase? (Section 4.18.3.1.2)

6A.71 Does the design contain a listing of the SPDs for the protection of signal, data, and communications systems and do the SPDs have an Imax rating of at least 10 kA 8/20 µs or greater when installed at the entrance? (Section 4.18.3.2)

6A.72 Are the published voltage protection rating (VPR) for each mode of protection selected to be no greater than those given in NFPA 780, Table 4.18.4 for the different power distribution system to which they can be connected? (Section 4.18.4)

6A.73 Are the following facility ac surge protection requirements fulfilled? (Section 4.18.5)

a. Is the short-circuit current rating of the SPD coordinated with the available current rating of the supply panel to which it is connected IAW NFPA 70: National Electrical Code? (Section 4.18.5.1) NOTE: Provide the specific NFPA 70 reference to ensure compliance.

b. Is the maximum continuous operating voltage (MCOV) of the prospective SPD used when selecting a SPD to ensure the MCOV is greater than the upper tolerance of the utility power system to which the SPD is connected? (Section 4.18.5.2)

c. Are service entrances protected using Type 1 or Type 2 SPD in compliance with standards such as UL 1449: UL Standard for Safety for Surge Protective Devices, Edition 3? (Section 4.18.5.3) NOTE: Type 1: These devices are capable of discharging a very high lightning current, generally from earth to the power distribution system. They are installed in the main electrical switchboard when the building is equipped with a LPS. Type 2: These are surge protective devices designed to discharge the currents generated by indirect lightning strikes and causing induced or conducted over voltages on the power distribution network. They are installed in the main distribution switchboard.

d. Are SPDs at grounded service entrances wired in a line-to-ground (L-G) or line-to-neutral (L-N) configuration? (Section 4.18.5.4) NOTE: Additional modes, line-to-line (L-N) or neutral-to-ground (N-G) are permitted IAW Section 4.18.5.4.1.

e. For services without a neutral, are the SPD elements connected line-to-ground (L-G)? (Section 4.18.5.4.2) NOTE: Additional line-to-line (L-L) connections are permitted.

6A.74 Are the following communication surge protection requirements fulfilled? (Section 4.18.6)

a. Are SPDs provided at facility entrances for all communication systems (including but not limited to CATV, alarm, and data) and antenna systems? (Sections 4.18.6.1 & 4.18.2.4)

b. Has the selection of SPDs taken into consideration aspects such as frequency, bandwidth, and voltage? (Section 4.18.6.2)

c. Are SPD introduced losses (e.g., return loss, insertion loss, impedance mismatch, or other attenuation) within acceptable operational limits? (Section 4.18.6.3)

d. Are SPDs protecting communication systems grounded and compliant with NFPA 70: National Electrical Code, Chapter 8? (Sections 4.18.6.4 & 4.18.6.4.1) NOTE: The purpose of the SPD is to equalize L-L, L-N, L-G, and N-G potentials. While a good ground is important, a good bond is imperative. NOTE: SPDs shall not be grounded through a down conductor. See Section 4.18.6.4.3

e. In instances when the point of SPD grounding is more than 6 m (20 ft) away, is a supplementary earth electrode or electrode system installed at the SPD location? (Section 4.18.6.4.2)

f. For data and signal line protection, does the SPD provide common mode protection? (Section 4.18.6.4.4) NOTE: Common Mode: Surges and transients that present a voltage simultaneously on live and neutral with respect to ground. NOTE: Differential mode protection should also be provided when practical. Differential Mode or Normal Mode are surges and transients that present a voltage between the live and neutral wires.

6A.75 Does the installation of SPD conform to the following requirements?

a. Does the design require surge protection hardware be installed IAW NFPA 70: National

Electrical Code? (Section 4.18.7.1)

b. Does the design require SPDs to be located and installed so as to minimize lead length?

(Section 4.18.7.2) NOTE: Longer, or looped, SPD line and ground conductors increase the impedance of the SPD ground circuit. Increasing the lead length serves to increase pass-through voltage at the point where the SPD is wired into service equipment or a branch panel board. Consequently, it is essential to minimize lead length impedance in this circuit.

c. Are sharp bends or kinks avoided by properly routing interconnecting links? (Section 4.18.7.2)

d. Does the design require the SPD grounding conductor be installed in accordance with the manufacturer’s instructions? (Section 4.18.7.3)

e. Does the design require all SPD components to be accessible for inspection and maintenance?

(Section 4.18.7.4) NOTE: Some SPD units are provided with a failure indicator. This feature is recommended since it facilitates maintenance or test procedures. Where used, this indicator should be visible. Building maintenance should consider periodic inspection or testing of SPDs.

See NFPA 70B: Recommended Practice for Electrical Equipment Maintenance.

6A.76 Does the design require the resistance of the earth electrode system used in the grounding of SPDs comply with NFPA 70: National Electrical Code? (Section 4.18.8) NOTE: The effectiveness of the SPD is based on the impedance of the path to ground. A lower ground resistance minimizes voltage differences of conductor attached to SPDs near the service entrance and reduces the change of arcing or insulation breach. Consequently, it is essential to minimize impedance in this circuit.

6A.77 Are SPDs protected with consideration for the operational environment and according to the manufacturer’s instructions? (Section 4.18.9.1)

6A.78 Are all SPD system enclosures and other ancillary equipment listed for the purpose they will be utilized? (Section 4.18.9.2)

Corrosion Protection

6A.79 Do all facets of the design provide protection against corrosion deterioration due to the environmental conditions (e.g., salt water fog) at VAFB? NOTE: Ensure the A&E firm provides sufficient information to assess compliance with this requirement.

6A.80 Are copper components installed within 600 mm (24 in) of the top of a chimney or vent emitting corrosive gases protected by a hop-dipped lead or tin coating? (Section 4.3.2)

Miscellaneous LPS Requirements 6A.81 Upon design completion and installation, is a maintenance and inspection plan, to include maintenance guidelines, provided to the Range User? (Sections 8.8 and 8.9.1)

Remarks

Facility/Building Name/Number: Inspection Date:

Inspector’s Name(s):

SECTION 6B: LPS INSPECTION, MAINTENANCE, TESTING, AND TRAINING

EVALUATOR/INSPECTOR NOTES

(1) All references are to NFPA 780, 2011 Edition unless otherwise indicated. (2) References to AFI 32-1065 are to AFSPCSup1, dated 2/3/03. (3) LPS means Lightning Protection System. (4) SPD means Surge Protective Device. (5) In NFPA 780, all asterisks (*) refer to NFPA 780, Annex A (Explanatory Material). For the purposes of this checklist, asterisks should be treated as mandatory requirements. (6) Explain any checklist items marked “NO.” (7) Make any evaluator/inspector comments in the specific step block and/or use the Remarks section at the end of the checklist.

General. LPS inspection,…