Corpus sync: neutrality remakes, note hygiene, datasheet relocation, transformer-split cross-refs
---
title: Visual Display Units
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# Quality Assurance {toc}
−## Visual display units shall be the standard factory products of a single manufacturer regularly engaged in their production, furnished as complete assemblies rather than site-assembled from loose components. {note}
+## Visual display units shall be the standard factory products of a single manufacturer regularly engaged in their production, furnished as complete assemblies rather than site-assembled from loose components.
## Units of a given type throughout the Project shall be the products of a single manufacturer.
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## Surface and core materials of markerboards and tackboards shall meet the surface-burning class required for the occupancy and sprinkler condition under IBC Section 803, tested per ASTM E84.
−## A Class A interior finish requires a Flame-Spread Index of 25 or less and a Smoke-Developed Index of 50 or less; some occupancies and sprinklered spaces permit Class B (Flame-Spread Index 75 or less, Smoke-Developed Index 450 or less), but Class A is the safe institutional default and the assumption of this standard unless a lower class is documented. {note}
−
```datasheet
label: Required interior finish class (ASTM E84)
…5 unchanged lines
```
+## A Class A interior finish requires a Flame-Spread Index of 25 or less and a Smoke-Developed Index of 50 or less; some occupancies and sprinklered spaces permit Class B (Flame-Spread Index 75 or less, Smoke-Developed Index 450 or less), but Class A is the safe institutional default and the assumption of this standard unless a lower class is documented. {note}
+
## Wall-mounted units and their operable parts shall comply with the ADA Standards for Accessible Design and, where adopted by the authority having jurisdiction, ICC A117.1.
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## The writing surface material shall be as selected for the room's use frequency, with porcelain enamel on steel specified for classrooms, training rooms, and other rooms used multiple times daily.
−## Specifying a melamine surface in a room used several times a day is the most common and most regretted error in this section; melamine ghosts and stains within months of institutional use, and the cost difference to porcelain is recovered many times over in service life. {note}
−
```datasheet
label: Markerboard writing surface
…7 unchanged lines
```
+## Specifying a melamine surface in a room used several times a day is the most common and most regretted error in this section; melamine ghosts and stains within months of institutional use, and the cost difference to porcelain is recovered many times over in service life. {note}
+
## Where the design intent shows magnets holding paper to the board, the specified surface shall be inherently magnetic — porcelain enamel on steel, or glass over a steel backing — and melamine shall not be substituted.
−## Magnet support is not an aesthetic preference but a substrate fact: only a ferrous backing holds a magnet, so a melamine or bare-glass board will silently fail the design intent the first time a teacher reaches for a magnet. {note}
−
```datasheet
label: Magnetic writing surface required
…5 unchanged lines
```
+## Magnet support is not an aesthetic preference but a substrate fact: only a ferrous backing holds a magnet, so a melamine or bare-glass board will silently fail the design intent the first time a teacher reaches for a magnet. {note}
+
## The markerboard core shall be a rigid laminated assembly that holds the writing surface flat over its full span and resists denting from normal handling.
−## Honeycomb aluminum cores are the standard institutional choice because they are light and stay flat; particleboard cores appear in economy lines and add weight and warp risk in humid rooms. {note}
−
```datasheet
label: Markerboard core construction
…5 unchanged lines
```
+## Honeycomb aluminum cores are the standard institutional choice because they are light and stay flat; particleboard cores appear in economy lines and add weight and warp risk in humid rooms. {note}
+
## Tempered glass markerboards shall be fabricated from low-iron glass of the thickness scheduled and, where magnetic function is required, shall be furnished with a continuous steel backing panel.
−## Standard tempered glass markerboards use 1/4-inch (6 mm) low-iron glass; low-iron is specified so the writing surface reads clean white rather than the green cast of ordinary float glass. {note}
−
```datasheet
label: Glass markerboard thickness
…5 unchanged lines
```
+## Standard tempered glass markerboards use 1/4-inch (6 mm) low-iron glass; low-iron is specified so the writing surface reads clean white rather than the green cast of ordinary float glass. {note}
+
## The finished writing surface shall not deviate from a true plane by more than 1/8 inch over any 8 feet of length when the unit is installed.
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## Fabric tackboard color, where shown as selected by the Architect, shall be confirmed early enough to accommodate the manufacturer's lead time for non-stock fabrics.
−## Custom and designer tackboard fabrics commonly run an 8-to-12-week lead time; a late "as selected by Architect" fabric is a frequent cause of schedule slippage on occupied-building work, so the selection deadline belongs on the submittal schedule, not in the punchlist. {note}
−
```datasheet
label: Fabric face color source (Type IV)
…6 unchanged lines
```
+## Custom and designer tackboard fabrics commonly run an 8-to-12-week lead time; a late "as selected by Architect" fabric is a frequent cause of schedule slippage on occupied-building work, so the selection deadline belongs on the submittal schedule, not in the punchlist. {note}
+
## The tackboard core shall be a rigid laminated assembly faced as specified and shall hold pins without splitting or losing pinning resistance over its service life.
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## Anodized aluminum frame and trim shall receive a clear architectural anodic finish, Class II minimum (0.010 mm), conforming to AAMA 611.
−## Clear anodized Class II is the 80-percent-case default frame finish; painted aluminum to match millwork is a legitimate choice but requires an early color selection and may extend lead time, so it is a deliberate decision rather than a substitution at submittal. {note}
−
```datasheet
label: Frame and trim finish
…8 unchanged lines
```
+## Clear anodized Class II is the 80-percent-case default frame finish; painted aluminum to match millwork is a legitimate choice but requires an early color selection and may extend lead time, so it is a deliberate decision rather than a substitution at submittal. {note}
+
## A marker or chalk tray shall be furnished with each markerboard unless the Contract Documents specifically omit it.
−## The marker tray is the accessory most often assumed and least often specified; it is listed as an "accessory" in manufacturer literature, so a board ordered without explicitly calling out the tray arrives without one and becomes a punchlist item. {note}
−
```datasheet
label: Tray shelf
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```
+## The marker tray is the accessory most often assumed and least often specified; it is listed as an "accessory" in manufacturer literature, so a board ordered without explicitly calling out the tray arrives without one and becomes a punchlist item. {note}
+
## A display rail (map rail) is a hook-bearing extrusion for hanging maps and charts; a projection screen receiver is a track for a roll-down screen — they look similar at the top of a display wall, so each shall be specified explicitly to the function it serves. {note}
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## The cabinet glazing shall be tempered glass where the cabinet is located within 10 feet of an operable window, a skylight, or other high-ultraviolet or impact-prone location.
−## Acrylic glazing is acceptable in interior, low-UV locations but yellows and scratches under ultraviolet exposure; tempered glass is required near windows and skylights for both clarity retention and impact resistance. {note}
−
```datasheet
label: Bulletin board cabinet glazing
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```
+## Acrylic glazing is acceptable in interior, low-UV locations but yellows and scratches under ultraviolet exposure; tempered glass is required near windows and skylights for both clarity retention and impact resistance. {note}
+
## Where locking hardware is specified for a bulletin board cabinet and electric latching is required, the electric strike shall conform to ANSI/BHMA A156.31.
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## Sliding-panel and folding-panel systems hang their weight from a top track, which requires structural header blocking at the top of travel; if that blocking is not shown on the structural or framing drawings it surfaces as an RFI at rough-in, after the wall is closed. {note}
+## The panel system type shall be specified, and structural header blocking shall be shown on the framing drawings where a sliding or folding system is selected.
+
```datasheet
label: Panel system type
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## Units shall be furnished in the standard module width and height scheduled, with custom sizes used only where a standard module cannot fit the available wall.
−## The 96-inch by 48-inch unit is the 80-percent-case classroom and conference-room module; widths of 36, 48, 60, 72, 96, 120, and 144 inches and heights of 36, 42, and 48 inches are the standard catalog range. {note}
−
```datasheet
label: Unit width
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```
+## The 96-inch by 48-inch unit is the 80-percent-case classroom and conference-room module; widths of 36, 48, 60, 72, 96, 120, and 144 inches and heights of 36, 42, and 48 inches are the standard catalog range. {note}
+
+## The mounting type shall be specified, coordinated with the unit size scheduled so the assembly fits the available wall.
+
```datasheet
label: Mounting type
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default: 10
```