Appendix B - HC102812R0067.pdf

APPENDIX B

Excerpt from CSI 360-95-3, Facilities Standards

09 69 00 Access Flooring

References

• NFPA 75 - Comply with the requirements of NFPA 75: Protection of Electronic Computer/Data

Processing Equipment.

• Ceilings & Interior Systems Construction Association (CISCA) – Test and Procedures for Access Floors

• Consult the Architectural Graphic Standards, Ninth Edition, by The American Institute of Architects;

publication for stringer type and descriptions.

Access (raised) flooring is not a requirement for design and implementation in DISA datacenters.

Access flooring in legacy datacenters has a design limitation in the amount of cooling air that can be forced through the perforated floor tiles to cool equipment (bulk average of approximately 3500W or 1 ton per standard 2’x2’ tile). Based on increasing IT equipment heatload densities, solid floors shall be considered for new datacenters (see section 09 62 00).

System Description Legacy DISA computer rooms shall have an accessible access (raised) floor system with sufficient accessible space between the finished working floor and structural floor to install service conduits, piping, wiring, and media for air plenum. The raised flooring may also be installed in areas of possible computer room expansion (such as tape library and supply rooms).

All components of the access flooring system shall be non-combustible Class A rated. Structural floor capacities and limitations shall be considered in the design and selection of the raised floor system. If the system is to be located in a seismic zone, additional detailed guidelines for construction apply.

An access floor system is an elevated floor area upon another floor (typically a concrete slab in a building). This raised floor consists of interchangeable 2' x 2' floor panels, generally manufactured with steel sheets, welded construction filled with lightweight cement to provide a strong, quiet accessible floor structure, that are supported by adjustable understructure support pedestals. The space between the raised floor and the slab allow running any building services, including electric power, data, telecom/voice, environmental control and air conditioning, fire detection and suppression, security and so on.

Access floor systems for use in DISA data centers shall be interoperable throughout the enterprise, such that floor tiles can be moved between data centers when needed to meet floor and plenum requirements. DISA has conducted lifecycle cost analyses of the different construction methods and different panel strengths, and have determined that the lowest cost over a raised floor’s design lifetime (20 years) is met solely by the floor panel system described herein. Beginning with the reasonable engineering assumptions that: (1) The lifetime of a ConCore 2500 panel system is 20 years, and (2) the lifetime of weaker panel systems is linearly proportional to the design strength of the panels:

ConCore Strength: 1250 1500 2500

Lifetime (Years): 10 12 20

Cost (Installed): $73,950 $76,990 $92,450

Cost/Year: $7,395 $6,415.83 $4,622.50

Annualized Cost Factor:

1.599784 1.387957 1.000000

Using figures submitted for three options in the 2006-7 silo room remodel at Ogden, over the design life of the raised floor the CC2500s are 38% more cost efficient than the CC1500s and 60% more efficient than the CC1250s.

Floor Panel Construction & Design Materials The floor panels shall be cold rolled steel and welded construction. Metal-clad plywood or metal-clad particle board panels shall not be used in new construction or facility modifications.

Exposed metallic surfaces shall be coated with epoxy paint finish or hot-dipped galvanized (HDG) for corrosion resistance. Use of electrodeposited galvanized tiles, known for spontaneous zinc whiskers formation, is not acceptable. Panels shall be internally filled with a lightweight cementitious product (for example, “ConCore”) for maximum strength and workability. Access floor systems used by DISA shall not be cornerlock.

Test Methods There are no industry standards for access floor loading performance that all manufacturers agree upon. The Ceiling & Interiors Systems Construction Association (CISCA) publishes "Recommended Test Procedures for Access Floors" which establish procedures for testing of:

concentrated loads, ultimate loads, rolling loads, stringer loads, pedestal axial loads and pedestal overturning moment loads. These test procedures do not set standards for test results. Products used in DISA facilities shall be tested and certified in accordance with the CISCA publication.

Test methods for concentrated, ultimate, rolling, overturning movement, and axial loads shall be in accordance with the "Recommended Test Procedures for Access Floors" as published by

CISCA.

Test Method for Impact Load: Panel without floor covering shall be supported on actual understructure. An impact load is applied to the panel via a one square inch indentor which is struck by a predetermined load dropped from a height of 36". The panel shall be loaded at its weakest point. Weakest point to be determined by an independent test lab.

Test Method for Electrical Resistance: Resistance to ground of all ESD-protective flooring from any point on its surface must be:

• Greater than 1 x 105 (100 thousand) ohms

• Less than 1 x 108 (100 million) ohms

The test is modified for access floors where one electrode is placed on the floor surface covering and the other electrode is attached to the understructure.

Dimensions Thickness shall be as required for structural strength. Floor panels shall be 2-ft x 2-ft square.

Dimensional tolerances as follows: (1) Flatness: ±0.02-in on any diagonal measure. (2) Length:

±0.015-in on any side measure. (3) Squareness: ±0.02-in between any panel lengths. (4) Finished flooring levelness: ±0.062-in within any 10-ft radius distance Concentrated Load Strength A concentrated load of 2500 pounds (1134kg) concentrated on one square inch at any point on the panel with maximum deflection of 0.080 inch with a safety factor of 2.0 based on static design load and with maximum permanent deflection of 0.010 inch.

Uniform Load Strength 625 lbs (284kg) per ft² with maximum deflection of 0.04-inch or less. Permanent set after application of concentrated load shall not exceed 0.010’’.

Rolling Load 10 passes of 1500 pounds (680kg) applied through a 3-inch diameter by 1-13/16 in wide phenolic caster with a deflection of 0.04-inch or less and with permanent deformation of 0.02-inch or less;

10,000 passes of 2000 pounds (907kg) applied through hard rubber (alathane) surfaced wheel of 8-inch diameter by 5-inch wide over the same path with permanent deformation not exceeding

0.010 inch.

Impact Load Panels and supporting understructure shall withstand without failure an impact load anywhere on the panel of 150 pounds (68kg) dropped from a height of 36 inches onto a one square inch area.

Failure is defined as the point at which the panel will no longer accept the load.

Perforated Tiles Use only equivalent 1-ft² open-face area (25%) perforated tiles on raised floor computer rooms.

Dampered or flow-controlled perforated floor tiles are not permitted. Perforated tiles shall be all steel welded construction (not concrete core) and shall be capable of supporting a concentrated design load of 1250 lbs, 300psi uniform load, and 2500 lb ultimate load. Design airflow for perforated tiles is shown below. This data, along with the temperature rise in the cooling air, determines the cooling capacity of each perforated tile. (Note that design static pressure is discussed in section 23 32 36.)

Raised Floor Finish Low-sheen matte High Pressure Laminate (HPL) is specified on access flooring around sensitive equipment because of its excellent ability to dissipate static electricity (ElectroStatic Discharge, or ESD). Material shall equal or exceed performance standards set by ANSI (American National Standards Institute)/NEMA (National Electrical Manufacturers Association) Publication LD3-1991 for high-pressure decorative plastic laminate.

Floor coverings in computer rooms must be a high-pressure light color plastic laminate at least 1/8 inch thick (Grade FL-12 or equivalent). Laminate shall not separate from tile with rolling loads or impact. Vinyl edge trim for the tile coverings shall be mechanically locked and bonded to the panel surface and flush with the surface covering. Carpet covered floor panels are not permitted in raised floor computer rooms. Wax and anti-static coatings on the raised floor are likewise prohibited.

“Gray Starlite” (ST-6-1) is the standard color selection for access flooring at DISA. The white background is complimented by swirls of light gray. This pattern effectively hides surface dust extremely well. It has been the standard

Static Pressure (Inches H20)

Airflow (CFM)

.01 230

.025 390

.05 525

.10 725

.15 900

.20 1050

.30 1250

.40 1420 color for computer room floors for over 30 years. Other names for this color include Gray Twirl, Gray Ripple, Raised Floor Ripple and Gray Tone. The standard color edge trim with these panels is black. It's light reflective value is 73.2%.

Standard grades of laminated floor tile have a volume resistance in the range of 5 x 105 to 2 x 1010 ohms at 500 volts when tested at 50% RH and 72 degrees F. Typical values for volume resistance will be in the 10 ohm range, depending on the laminate thickness. Once installed, the floor's static performance will be regulated by how clean the panels are kept. HPL must be kept clean and free of residuals in order to perform. In addition, the floor's electrical properties will be affected by humidity, adhesives used, panel paint system and the overall continuity to ground.

Stringer Construction Stringerless and snap-on stringer systems are prohibited. The raised floor system must be bolted stringer-type construction. Stringers must be fabricated of extruded aluminum or rolled steel and capable, without panels in place, of supporting a concentrated load of 250 pounds at mid-span of the stringer without exceeding yield strength and without a permanent deformation greater than

0.01 inch. Stringers shall have conductive gaskets. Stringer system shall not be cornerlock.

Stringer design shall be 2’2’, 2’4’, or 4’/4’ as shown.

Pedestal Construction Materials and Strengths Panels shall be supported by adjustable pedestal assemblies which positively locate, engage and secure panels and which accommodate horizontal stringer members. Provide pedestals of steel or aluminum capable of carrying a 5,000 pound axial load without permanent deformation.

Provide permanent factory applied corrosion resistant finish for pedestals made of ferrous materials. Provide base plate not less than 4-inch x 4-inch x 1/8 inch thick, welded to shaft of pedestal. Pedestal shall be secured to the supporting floor to resist a minimum overturning moment of 1000 inch-pounds applied laterally at the top of the pedestal.

Cap Assembly Caps shall fit precisely over pedestal shafts to interlock panels and stringers to prevent tilting, rocking, or vibrating of panels when live load is applied. Caps shall be height adjustable with bolt & thread assembly and permit leveling of floor system with adjustment range of approximately two inches. Mount pedestals such that height is adjustable from the top. Do not secure adjustable end of pedestals on the subfloor slab. Provide lock nuts, set screws, or other locking devices to positively lock final pedestal vertical adjustments in place, independent of floor panels.

Installation & Leveling Installed access floors shall be level within plus or minus 0.060 inches in 10 feet, and plus or minus 0.10 inches over the entire area. Floor to be rigid and free of rocking panels.

Stairs, Ramps and Railings

Stairs, ramps and railings must meet American Disabilities Act (ADA) requirements. Ramps should have a maximum slope of one inch per foot. The surface should be non-slip. There must be a level platform at the top and bottom. Platforms must be located at not more than 30 feet intervals and at every turn. Ramps must have at least one handrail at the 32-inch height that extends one foot beyond the top and bottom of the ramp. Railings must be installed on both sides of stairs, and on ramps wider than 44 inches, or when both sides are open.

Spare Materials Spare cutout trim, floor panels, stringers and pedestals must be maintained available at the site. New installations and construction shall include an additional 10% of total parts and equipment for spares.

Seismic Considerations

• Facilities in seismic zones

II, III, and IV must comply with the following criteria:

• Moment Resistance – A moment resisting floor system providing maximum accessibility must be installed while avoiding use of diagonal bracing.

• Mechanical Fastening – Secure by mechanical fastening if pedestal overturning moment due to seismic force exceeds 1,000 inch-pounds in addition to adhesives.

• Equipment Anchoring – Floor mounted equipment shall be anchored to the floor system to prevent accidental tipping; alternatively provide a separate support system.

• Interlocking – Stringers and other framing members must be rigidly bolted to the pedestals to preclude relative lateral movement.

Vertical Clearance from Raised Floor to Ceiling The height from the top of the raised floor to the bottom of the ceiling above shall be 10 feet or higher to sufficiently accommodate modern equipment, with a maximum height of 8 feet, and provide at least 18 inches above it for proper operation of fire detection systems, fire sprinkler systems (per NFPA 13 8-5.6) and air flow.

Elevations & Leveling The height from the top of the structural floor deck to the top of any raised access flooring system shall be at least 18 inches in DISA space. New constructions and feasible modification of all floors shall be at finished level to avoid installation of stairs and ramps. This is a mandatory requirement in new construction.

Grounding Ground access floor system for safety hazard and static suppression. Connect access floor support system to building grounding electrode(s) in accordance with NFPA 70, National Electrical Code. Provide positive contact between components for safe, continuous electrical grounding of entire floor system. Total system resistance from wearing surface of floor to building grounding electrode shall be within range of 0.5 megaohms to 20,000 megaohms.

Fire Detection System

An automatic smoke detection system shall be installed below all raised access flooring in accordance with NFPA 75 Para 6-2.1b/c. DISA fire detection system standards for new construction and renovations require laser particle detection systems.

Drainage and Leak Detection Comply with NFPA 75: Para 3-3.2 "A structural floor shall incorporate provisions for drainage from domestic water leakage, sprinkler operation, coolant leakage, or fire fighting operations."

Recessed subfloors require gravity-flow drains. Provide backwater valves and emergency pumps to avoid flooding if there is danger of water accumulation or backing up through the drainage system. Subfloor shall be monitored by a centralized leak detection system