Technical consultation on specifications and quality control of netting materials and mosquito nets
6. UPDATED WHO SPECIFICATION FOR NETTING MATERIALS AND MOSQUITO NETS
6.1 Description (refer to note 1)
The product shall be in the form of a net of …[conical, rectangular, etc,] shape, having dimensions of …[dimensions in metres]. It shall be made of netting, consisting of …[denier/decitex, mono-/poly-filament, polymer type] fibres. The product shall appear clean and shall be free from visible extraneous matter, visible damage (such as splitting or tearing) and visible manufacturing defects (such as poorly made seams or a weave that is either not uniform or too loose to remain uniform in use), and shall be suitable for use as a mosquito net.
Physical properties (refer to notes 2 & 3)
Mesh count (note 4)
When counted by the method given in Note 4, the average number of complete holes/in2 shall be not less than 156 and the lowest value shall be not less than 148.
6.2.2 Bursting strength (note 5)
The minimum bursting strength of the fabric shall be declared (not less than 250 kPa1) and, when determined, the average shall be not less than that declared. If seams are present, their average bursting strength shall be not less than the average for the fabric.
6.2.3 Dimensional stability (note 6) Not more than 5% shrinkage/expansion in both dimensions.
Other characteristics (colour, number of filaments in the yarn, filament texture, etc.) may be specified separately, according to the requirements of the application.
Nets should be tested for compliance with all clauses in the specification. The number, frequency and distribution of nets, within and between batches/consignments, to be
1 KiloPascal: a unit of pressure. 1 kPa is approximately the pressure exerted by a 10-g mass resting on a 1 cm2 area – 101.3 kPa = 1 atm.