• AAR: An After Action Review (AAR) is an assessment conducted after a project or major activity that allows employees and leaders to discover (learn) what happened and why.
• Bay: A single modular section of a fabric structure, typically 15' or 16'4" (5m) long. When joined together with other bays, they make up the whole shelter structure. Bays can be added or taken away at any time, a feature most popular with temporary warehouses or those with seasonal warehousing needs.
• Beam Cover: A flap of fabric membrane that stretches from one roof panel over to the next roof panel, covering the top of the aluminum rafter. The beam cover is secured using industrial Velcro or heat-sealing the membrane.
• Bravo-Zulu: Modular thermoplastic flooring that is composed of 4' x 4' panels. Frequently used inside vehicle maintenance shelters, as portable helicopter landing pads, and as temporary roadways over muddy or sensitive environments.
• Clear Span: There are no columns supporting the roof from one wall across to the opposite wall, allowing free use of all interior space.
• Dead Load: The load on a structure produced by its own self-weight.
• Dressing: The term describing the important final adjustment process after the structure has been raised and the fabric membrane installed.
• Eave: The lower edge of the structure's roof.
• Egress: The planned avenue to leave a structure safely.
• Entrance Canopy: An awning for a permanent building or from a temporary pavilion structure to the driveway or street. Canopies define the entrance from a distance and provide additional shelter for guests, especially smokers.
• Fabric Membrane: The material composing the roof and some sides of Mahaffey structures. It is typically a PVC coated polyester known as Ferrari Precontraint.
• FAA: Federal Aviation Administration
• Flame Resistance: A measure of the property of a material which prevents or retards the passage of excessive heat, hot gases or flames under conditions of use.
• Super Series Series: The family of Mahaffey structures commonly used for rapid response situations of a temporary or semi-permanent nature where snow loads are not an issue.
• Footplate: The metal base that supports a fabric structure and is attached to the ground using steel stakes.
• Gable: The vertical, flat, triangular end wall of a building or structure.
• GSA: General Services Administration
• Guardian: The Mahaffey trademark for insulated steel walls used most commonly on seasonal warehouses and portable shelters set up for long-term projects.
• Gusset: A steel plate for strengthening the angle between the upright and rafter on the MegaStructure.
• HVAC: heating / ventilation / air conditioning
• Hip: The line of the structure's roof running from the top of the end down to the corner. Most Mahaffey structures have flat gable ends, but hip roofs offer a more traditional architectural appearance.
• IBC: International Building Code. The single set of comprehensive and coordinated national model construction codes created by the merger of several regional organizations-the Building Officials and Code Administrators International (BOCA), International Conference of Building Officials (ICBO), and Southern Building Code Congress International (SBCCI).
• Keder: A welt of fabric attached to the edge of a fabric membrane panel and used to securely slide through grooves within the aluminum rafter.
• Kip: A unit of force equal to 1,000 pounds.
• Life Safety: The equipment necessary for prudent emergency planning including fire extinguishers, illuminated exit signs, battery powered lighting, etc.
• Liner: Secondary interior membrane, usually non-structural, used within environmental enclosures or as a decorative element within entertainment pavilions
• Live Loads: The weight super-imposed on a structure by its use and occupancy, not including wind load, snow load, earthquake load or dead load.
• Louver: An opening provided with fixed or movable slanted fins to allow flow of air.
• Mahaffey: The preeminent manufacturer of fabric structures, founded in 1924. Mahaffey structures are used throughout the world as seasonal warehouses, environmental enclosures, entertainment pavilions, construction covers, and disaster relief shelters.
• MegaStructure: Mahaffey's family of structures specially engineered for winds up to 130 mph with snow loads of 30 psf. These structures are well suited for semi-permanent applications where the ability to relocate and recycle a building are important attributes.
• Mobile Structures: Interchangeable term used to describe Mahaffey's line of portable storage shelters and temporary pavilions.
• Modular Building: Another term used to describe a portable structure or temporary warehouse constructed of fabric-clad aluminum framework. Mahaffey's structures are modular and allow bays to be added or taken away as needed.
• MVP: Mahaffey Valued Partner, a regional affiliate that represents Mahaffey and sub-leases structures from us.
• Negative Pressure: Using vacuum equipment to remove and filter air from within an environmental enclosure used to shelter a hazardous material remediation site.
• Occupant Load: The total number of people permitted to occupy a structure, or portion thereof, at any one time.
• Pitch: The vertical distance of a structure measured from the eave to the top of the tent roof.
• Purlin: Lightweight aluminum member that connects rafter to rafter.
• Rafter: The primary structural support connecting the eave to the ridge of the structure. Rafters come in a variety of sizes, but each is formed with grooves to secure the keder edges of the fabric panels.
• Ridge: The line defining the longitudinal axis of the structure roof; this line runs along the center and is the highest point of the roof.
• Safety factor: A co-efficient used in all good design, which takes into account various uncertainties such as variations in material properties, weather, load experience, fabrication and construction tolerances, etc. The use of appropriate safety factors is not optional.
• Scrim: Mesh like fabric used as a base material in coated and laminated fabrics.
• Shear: A force tending to make two contacting parts slide upon each other in opposite directions parallel to their plane of contact.
• Sidewalls: The walls installed around the perimeter of a structure, typically composed of detachable fabric or insulated steel.
• Stakes: Pointed steel rods driven into the ground to anchor a portable structure.
• Snow Load: The assumed gravity forces acting on a structure due to the weight of snow, which also includes any necessary accounting for drifting or sliding.
• Temporary Structure: As specifically defined by the individual applicable code, but generally taken as a structure which will be in place for less than 180 consecutive calendar days.
• Tension Structure: A tent designed to have all perimeter loading equally distributed over a series of catenary arches, providing great stability.
• TOC: Tactical Operations Center
• Uplift: Wind load on a seasonal structure or semi-permanent structure that causes a load in the upward direction; partial vacuum from wind loads on a temporary warehouse that causes a load in the outward direction.
• Upright: The aluminum columns that support the periphery of a fabric structure.
• Wicking: A phenomenon that occurs when moisture accumulates at the edge of the fabric (where substrate yarns may be exposed) and is drawn into the fabric scrim. This moisture can result in unsightly "stains" from fungus and algae within the fabric. Mahaffey uses fabric impregnated with fungicides to prevent damage from wicking.
• Wind Load: The pressure on a structure due to wind blowing in any direction.