Technical consultation on specifications and quality control of netting materials and mosquito nets
Specifications for, and quality control of, netting materials (fabric) and mosquito nets are important to define acceptable physical properties (e.g., strength, barrier properties, uptake of insecticide solution) of mosquito netting and nets for institutional buyers and end users. These specifications help to ensure that the net does what it is intended to do for the user.
In June 2000, WHO proposed minimum specifications for the physical characteristics of polyester netting material, the most commonly used material for mosquito nets. These specifications were developed primarily for institutional buyers and national malaria control programmes, to provide guidance for procurement as well as to facilitate quality control of mosquito nets.
Consequent to experience in this area acquired during the following five years, there was a need to update the specifications that have been proposed earlier. Some of the test methods were not clearly defined, or were difficult to use reliably or had to be modified. Moreover, certain limits initially proposed proved to be either too stringent or insufficiently stringent. Further, a new material, high-density polyethylene (HDPE), is currently widely dissemi- nated and netting materials based on other new technologies are either becoming available or are in development.
Large-scale procurement of mosquito nets is now routinely being under- taken by institutional buyers, NGOs and national control programmes. Simple and practical guidelines are therefore needed to help inexperienced buyers, especially in national malaria control programmes, to address the issue of quality during procurement and subsequently to maintain adequate quality control.