General Specification

• This generic specification describes a prefabricated modular Air Shower enclosure to be used for removing surface particles from personnel prior to entering a Cleanroom work area.
• The Air Shower shall be a high velocity, low pressure type system in accordance with Federal Standard 209E and Air Force Tech Order 00-25-203.
• The Air Shower will provide normal entrance to and exit from a contamination controlled area.
• The workmanship and materials shall be professional quality and esthetically pleasing.
• The Air Shower shall be assembled and tested in the factory, then disassembled for shipping and field assembly.

Construction

• The Air Shower shall be a completely self contained unit, equipped with air filtration systems, blowers, motors, controls, solid-state programmable microprocessor, interlocking doors, lighting, and pre-wired electrical panel.
• All exterior and interior Air Shower surfaces shall be completely sealed with materials compatible with Class 1/10 cleanroom construction standards.
• All visible surfaces shall be covered with high-pressure, white plastic laminate. Trim shall be clear anodized aluminum. Optional: Clad all visible surfaces with .040” clear anodized aluminum.
• Air Shower interior air duct surface shall be completely covered with plastic laminate, Melamine laminate, clear anodized aluminum, or other suitable surface covering compatible with Class 1/10 Cleanroom.
• Doors made from clear anodized aluminum and .25” tempered glass shall be used at the entry and exit of Air Cleanroom envelope.
• Adjustable air nozzles shall be white plastic construction sized and spaced to provide average 7,000 fpm air flow at the face of the nozzle.
• Return air registers shall be white baked enamel steel grilles, built into the Air Shower wall system.
• Interior ceilings shall include an appropriate number of air nozzles and a fluorescent light, or HEPA filters and lighting above a protective grille (on models with laminar flow ceilings).
• Pre-drilled and capped sprinkler penetrations shall be provided.

Filtration System

• HEPA filters capable of removing 99.99% of dust particles to 0.3 microns in size (optional: ULPA 99.9995% on .12 micron) shall be used. Filter access is from above unit, or as specified.
• Air Showers which are specified to include optional Constant Purge ceilings shall have fan-powered HEPA filters mounted above a polystyrene egg crate diffuser panel. The Constant Purge feature shall add 6” to the standard Air Shower height.
• Replaceable pre-filters of 30% efficiency shall be used to maximize life of the absolute filters and shall be accessible from Air Shower interior, within return air grille(s).

Control System

• A Programmable Logic Controller (PLC) shall be used to control the sequence of operation of the Air Shower.
• An Emergency Off button (EMO) shall be located inside the Air Shower in a conspicuous location.
• Activating the switch shall cause the cycle to immediately end, and release all interlocks. Lights shall remain on.
• Door sensors shall be 24 volt DC magnetic reed switches. Door interlocks shall be 24 volt, located in the doorjamb at the top of the entrance and exit ways. All locks shall automatically release upon loss of power or when the (EMO) button is pressed.

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