P/00/009 Regulation 3.2B AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION FOR AN INNOVATION PATENT Invention Title: POLYMER GRID BACKED SAFETY MESH The invention is described in the following statement together with the best method of performing it known to us: Our Reference; 116008 - 2 Polymer Grid Backed Safety Mesh Technical Area The present invention relates to building construction 5 safety and protection facility and device. Specifically, it includes a safety mesh comprising a polymer strap grid with high strength. Background 10 According to relevant regulations, on building construction sites, protective mesh must be installed on the outer side of scaffolding during or after the scaffolding is erected in order to prevent falls of workers, tools, material or debris from the building. The current widely used protective mesh is 15 single layer of woven or knitted polymer net. It has the characteristics of flexibility, easy to carry, and easy to install and dismantle. However, it is poor in durability, impact ability and anti-burst ability. It often becomes worthless after a period of time and use because of material ageing and 20 UV impact. It often develops holes, or further tears in parts, and eventually loses its protective function. Brief Description of Invention The purpose of the present invention is to provide a new 25 polymer strap grid backed safety mesh to solve the unsafe problem of the current mesh with its poor anti-bursting and anti-impact ability, to achieve the goal of a long life span, and high reliability for safety protection on construction sites. 30 The present invention provides a polymer strap grid backed safety mesh. It is constructed as a polymer strap grid with a layer of woven or knitted mesh or fabric. The embodiments 5 of the present invention are comprised of spaced apart high strength polymer straps to form horizontal elements and vertical elements. The said woven or knitted fabric sheet is fixed to one side of the said strap grid. The polymer grid backed mesh of the present invention is 10 characterised by light weight, high tensile strength, high flexibility, due to the combination of the said grid and woven or knitted fabric. It greatly improves the anti-impact ability, and effectively increases anti-bursting ability, as well as increasing the life span of the product and therefore increasing 15 the reliability of protection on sites. Accordingly, in a first broad form of the invention, there is provided a polymer grid safety protection mesh, comprising a strap grid, and woven or knitted fabric, for use on an outer side of scaffolding; said strap grid formed of high strength 20 polymer material, comprising spaced apart horizontal straps and spaced apart vertical straps; said woven or knitted fabric being attached on one side of said strap grid. Preferably, said grid and woven or knitted fabric are made of a polymer material; said polymer material including 25 polyethylene (PE), and polyethylene terephthalate (PET). Preferably, said horizontal straps and vertical straps in one integrated processing may manufacture the said grid sheets. Preferably, the said horizontal straps and vertical straps are made of high strength polymer material, and may be formed 30 elongate, and flat shape through the process of injection, or/and stretching, or/and weaving and knitting. In another broad form of the invention, there is provided a polymer grid and fabric safety mesh for attachment at the outer perimeter of scaffolding; said grid comprising spaced 5 apart horizontal and vertical straps; said straps formed of side by side woven bundles of polymer strands; said horizontal and vertical straps at least partially heat fused and sewn together at their cross over points; said fabric comprising a polymer woven or knitted cloth attached to one side of said 10 grid. Brief Description of the Drawings Embodiments of the present invention will now be described with reference to the accompanying drawings wherein: 15 Figure 1 is a front view of a portion of a sheet of safety mesh according to a first preferred embodiment of the invention, Figure 2 is a front view of a portion of a sheet of scaffolding safety mesh according to a second preferred 20 embodiment of the invention, Figure 3 is a front view of a third preferred embodiment of the invention; Figure 4 is a front view of fourth preferred embodimemt; Figure 5 is a front view of fifth preferred embodiment; 25 Figure 6 is a rear view of the fifth preferred embodiment of figure 3; Figure 7 is a sectioned view A-A of the fifth preferred embodiment of figures 5 and 6. 30 - 5 Detailed Description of Preferred Embodiments First Preferred Embodiment With reference to Figure 1, in a first embodiment the scaffolding safety mesh 10 is formed of a first series of 5 parallel longitudinal polymer strips 12 and a second series of parallel transverse polymer strips 14. In this instance the first series of longitudinal strips 12 and the second series of transverse strips 14 are interwoven so that each strip of first series alternately lies at a first side of a strip of 10 the second series and at an opposite second side of the strip of the second series where the strips intersect 16. At least a proportion of the intersections 16 of the strips of the first series and the second series are joined together. Preferably alternate intersections along a given 15 strip are so joined, with alternate intersections along the next parallel adjoining strip also joined but staggered relative the first strip as shown in Figure 1 (indicated by "X"). The joining of strips 12 and 14 at the intersections 16 may be effected by various means, for example by heat welding, 20 riveting as indicated in Figure 2, or with a suitable adhesive. Preferably, the grid of this embodiment is provided with a polymer woven or knitted fabric such as shade cloth for example, attached to one side of the grid formed by the polymer straps as shown in Figure 3. 25 Second Preferred Embodiment In a second preferred embodiment of a scaffolding safety mesh 100 shown in Figure 2, the strips 112 and 114 making up the grid of the mesh, are not interwoven but form two layers, - 6 made up of a first array of parallel longitudinal strips 112 overlaid by a second layer of parallel transverse strips 114. Again these are interconnected at least in a regular pattern, either at staggered alternate intersections as described 5 above, or at every intersection. In both the above described embodiments, a typical spacing of the grid forming the mesh is at 40mm by 40mm. However it will be understood that a denser grid of straps can be employed to increase impact and penetration characteristics. 10 In this embodiment also, a woven or knitted polymer fabric is attached to one side of the polymer grid as shown in Figure 4. Further Preferred Embodiments 15 As shown in the Figures 3 to 7, the safety mesh according to further preferred embodiments the invention, is again comprised of a polymer strap grid and woven or knitted fabric. The said strap grid is made of high strength polymer material and is comprised of horizontal Straps (1) and vertical Straps 20 (2), which are spaced apart. The said woven or knitted fabric is fixed on one side of the said strap grid. The said high strength material may include polyethylene (PE), and polyethylene teraphthalate (PET) . It may also be made of other suitable high strength polymer material with similar strength 25 criteria and similar function of usage. The said horizontal straps (1) and vertical straps (2) are made of the above mentioned material, and become either flat solid straps or flat fabric straps, through the processes of extrusion, or stretching, or weaving, or knitting, or stitching. 30 In one preferred arrangement, the straps of the grid are formed of side by side flattened bundles of multiple woven polymer strands. Preferably the straps are formed of at least three, preferably four such bundles. The bundles of the 5 horizontal straps and vertical straps may be at least partially heat fused or welded and/or sewn together at their cross over points and further linked at these cross over points by a sewing process. In a further, or simultaneous process, heat may be applied to the assembled strap grid to cause at least partial 10 fusion as well between the strands of the bundles and between the bundles themselves. The formation of the said strap grid may have various patterns. It may be formed, as shown in Figure 3, via weaving of the horizontal straps (1) and vertical straps (2), and 15 applying adhesive or heat welding at the cross over points. It may also be formed, as shown in Figure 4, through the process of the horizontal straps sheet, and the vertical straps sheet forming separated layers and applying adhesive or heat welding at the cross over points. It also may further be formed, as 20 shown in Figures 5 and 6, by way of the horizontal straps (1) and vertical straps (2) forming the whole sheet of strap grid in one integrated process through material injection, or stretching, or weaving and knitting, or casting, or pressing. In the example shown in Figures 6 and 7, the connections 25 and fixing of the strap grid and the woven or knitted fabric are realised by the edging strap (4), and the round knot (5) at the crossing of horizontal straps and vertical straps. The above connection and fixing may be press and welded using ultra sound plastic welding machine to make sure the woven or knitted 30 fabric to be secured between the strap grid and the edging straps, -8 or the knots. Further, the connection and fixing of the strap grid and woven or knitted fabric can also use the method of weaving and knitting, or other methods, which are not explained here 5 Specifically, the woven or knitted fabric (3) according to the invention, is attached on one side of the strap grid sheet. It is not located between the said horizontal straps and vertical straps. This arrangement has the advantage of relative ease of replacement of damaged woven or knitted fabric from 10 the strap grid, since the material of the strap grid is much more durable than that of the woven or knitted fabric.