GLOSSARY PROTECTIVE CANOPY
Term | Definition |
---|---|
± 2% | unit of variation; plus or minus that percentage from the stated value |
Wind protection benefits | A well-designed wind-break will not be totally impermeable; but it will reduce the force of the wind, helping to maintain humidity and temperature; and keeping turbulence to a minimum in the sheltered zone – up to a distance of almost ten times the height of the structure. |
Wind Load | The pressure on fabric or a structure caused by winds of a certain stated speed |
Wind Force | Its full name is the Beaufort wind force scale, although it is a measure of wind speed and not of force in the scientific sense. Wind force is what you feel when you try to stand up in a strong wind. Wind force is what blows the dust, bends the trees etc. |
Weft | Yarns running across the fabric. |
Warp | Yarns running along the length of the fabric. |
Vapour pressure difference | The weight per unit area of the vapour particles in the air. |
UV Light | The UltraViolet part of the light spectrum. having or employing wavelengths shorter than light but longer than X-rays; lying outside the visible spectrum at its violet end; “ultraviolet radiation”. |
UV Inhibitors / Stabilizers | Chemical additives added at the time of yarn manufacture to prevent the yarns from biodegrading due to the effects of UltraViolet light. |
UV Block vs Shade | Shade is the blocking of all light; UV Block only refers to the ultraviolet spectrum of light. |
Using Clip lock – Video | Instructional video on attaching netting to structures using Clip Lock. |
Turbulence | Unstable flow (of a liquid or gas). |
Throwover | Net or shadecloth placed over an item or plant for a short-term only; usually there is very little supporting structure other than the item or plant itself. Intended to be easily removed after it has served its purpose. |
Tensile Strength | Ultimate strength of the material subjected to tensile loading |
Sheltered zone |
|
Shade-house | A green-house style structure, covered in porous shade-cloth for the sole purpose of provided shade for the contents. |
Shade Levels | Shade levels under coloured and white fabrics are measured in PAR (photsynthetically active radiation). This is approximately equivalent to visible radiation; 100% shade is solid.A white fabric will typically have a shade level of about 7/10 of that of a black fabric of the same weave. |
Selvedge | The edge of a fabric that is woven so that it will not ravel or fray |
Retractable | Able to be pulled inwards, towards a center, or folded into a storable size or shape. |
Repairing Netting – Video | Sewing up a damaged net is quite straight forward. |
Raschel Warp Knitted | Raschel is a type of knitting machine named after the inventor. Cloth / net knitted on this machine is described as such. |
Q-Net | A proprietary term for Netpro’s specific brand of “quad”, “hex” or “hail-net”; net woven in such a fashion as to have any number of single strands crossing over the holes woven in the nets; divides the original hole into smaller holes. The net size is still referred to by the original hole size ie 12mm Qnet means the main hole is 12mm wide from side to side. |
Pre-Packaged | Cut and packaged in a pre-determined size; opposite of Cut to Order. |
PAR | Photosynthetically Active Radiation; approximately equivalent to visible light radiatio |
Pa | Pascal – the International System of Units (SI) unit of pressure, stress, and tensile strength; it is a measure of perpendicular force per unit area; ie equivalent to one Newton per square meter, or one Joule per cubic meter. |
Net / Shadecloth | Net refers to a fabric that is woven so as to stretch in one or both directions; Shadecloth is a stable material (does not stretch). |
N | Newtons – the International System of Units (SI) unit of force. One DecaNewton (daN, 10N) is roughly equivalent to the non-SI unit of force, kgf (the force exerted on |
Mullen Burst Strength | ASTM D 3786 diaphram method (Force required to break the yarns and burst a |
Monofilament | A single strand is used in the weaving process; the strand is flattened to a ribbon-like shape, rather than a thread-shape. |
Microclimate | Microclimate the average climatic conditions in a very localised area. Micro: extremely small in scale or scope; Climate: the weather in some location averaged over a long period of time. |
m | metre; mm – millimeter (0.001m); units of length |
Light spectrum | The ordered array of the components of light. The colour of the fabric influences the colour (or spectrum) of the light that is absorbed, and hence the spectrum “seen” by the plants. Black fabrics absorb all light equally. White and “clear” fabrics have a reduced effect on the ultra-violets, but a |
kPa | Kilo-Pascal (1000 Pa) |
kN | Kilo-Newton (1000 N) |
HDPP | High Density PolyPropylene |
HDPE | High Density PolyEthylene, has superior abrasion resistance compared to HDPP and is the preferred choice for horticultural / agricultural textiles. |
Grab Tensile Strength | ASTMD D 5034 grab method (Force required to break the warp and weft yarns). |
g/m2 | grams per square meter; unit of weight (1g = 0.001Kg); the force of gravity on matter |
Fire Rating | Fire resistance in terms of Australian Standard 1530 for Textiles (T3). |
Evapotranspiration | The term describing water loss from plants through emission of water vapour via the leaves by transpiration – can be a major form of stress for plants. Evaporation: the process of extracting moisture; moisture becoming a vapour, Transpiration: the emission of water vapor from the leaves of plants. |
Denier | Unit of Linear density equal to the mass in grams per 9,000 meters of yarn. |
Decitex (dtex) | Unit of Linear density equal to the mass in grams per 10,000 meters of yarn. |
Clip-lock | A patented design involving a metallic spring-form which locks into a gutter, in order to secure fabric between the two parts. Please refer to our “Components” Product Sheet for an image of Clip-lock. |
Climate Control | Control of wind-speed, humidity, and temperature factors. Extreme climate control would be a greenhouse with heaters, ventilation fans, and moveable screens in the roof. Porous canopies can achieve many of the same effects though to a lesser level, depending on the fabrics and supporting structures used. |
Broad-acre | Crops planted in an open field, possibly on trellises (berries, vines, fruit trees), or self supporting(trees, vegetables). |
ASTM | American Society for Testing and Materials |
Angled Sides / Wind barriers | When wind hits a vertical barrier it is thrown vertically. An inclined barrier throws the wind up at an angle. This more gradual process gives a longer flatter protected area behind the windbreak. |
Anchor | In this case, an underground mechanical device that fixes a cable or wire firmly in place and resists the tension placed on the cable. |
Air temperature profile | A record of the fluctuation of air temperature in the same location over a periodof time. |