I’ve always been a believer in using checklists all my working days, and I have written several columns here over the years directed towards different checklists (e.g., December 2016). Staying with this theme, here is a first start for a design engineer and mechanical coordinator accessibility checklist. This list addresses sheet metal access doors, access through gypboard walls, and gypboard ceilings. In addition, this list would include horizontal and vertical assess to equipment and/or components, as well as headroom:
Access door in sheet metal distribution at:
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Fire damper
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Smoke damper
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Automatic damper
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Flow measuring device
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Viewing glass access door to humidifier manifold
Access door in plaster ceiling structure or in walls to sheet metal access doors (noted above), pipe distribution, and/or terminal equipment such as:
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Exposed fire damper in vertical shaft wall serving return air plenum ceiling
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Exposed smoke damper in vertical smoke barrier wall serving exposed in return air plenum ceiling
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Exposed automatic damper vertical shaft wall serving return air plenum ceiling
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Control device (e.g., duct static pressure transmitters mounted on outside of sheet metal distribution duct).
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Air and water flow measuring devices
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Sheet metal volume damper and water balancing valve
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Air terminal device (e.g., VAV terminal)
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Air terminal with water piping and associated components (e.g., terminal heating coil)
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Downstream air filter unit mounted in sheet metal duct
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Shut-off valve
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Automatic control valve
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Inline circulator and piping components
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Water air vent
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Drain valve
Horizontal access space for equipment and/or components removal of:
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Coil removal
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Filter removal
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Fan shaft removal
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Motor
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Tube pull and/or tube cleaning
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Replacement of equipment at end of useful life
Access space to lower equipment that is hung from above within an equipment room:
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Utility fan
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Cabinet fan
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HVAC unit
When thinking about accessibility, the designer or the mechanical coordinator should take into account those who will need to gain access to control panel, devices, and equipment including the following trades:
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Piping contractor
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Sheet metal contractor
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Air and water balancing contractor
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Commissioning engineer
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O&M technician
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Service technician
Issues and concerns associated with accessibility are:
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Large enough access door in wall or ceiling to remove the piece of equipment or device behind the wall or above the ceiling
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Large enough access door in wall or ceiling for personnel to reach and service the device or piece of equipment
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Large enough access door in sheet metal distribution system to reach in and service the device or piece of equipment within this distribution system
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Pipes, ducts, and/or electrical conduits above the ceiling but directly below the device or equipment obstructing servicing
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Pipes, ducts, and/or electrical conduits overhead but directly below the device or equipment obstructing servicing in an equipment room
As a rule, underfloor access panels are an integral part of a raised-floor system, so the entire floor system should be accessible. If not, attention needs to be paid to what is below the floor that requires access and make sure there is an adequately sized access door in the floor system. Quite often, the mechanical coordinator will overlook just how long and wide an access panel or door needs to be for a person to get a ladder up through the ceiling structure allowing this person to then reach the device or piece of equipment for inspection and/or servicing. The same can be said for access ladders. If a technician has to climb a ladder to get to equipment about and/or on to the roof, consideration needs to be given to how this technician is going to climb a ladder while holding materials or tools (e.g., a box of 12-24-in by 24-in filters).
So what else can be added to this list of things to consider when it comes to access?