ZeroFly® Shelter - Quality Control

Vestergaard Frandsen maintains quality control standards necessary to meet WHOPES specifications. We have our own internal laboratories complying with WHO protocol. This ensures real time monitoring of quality.

Quality Control samples of ZeroFly® plastic sheeting are taken randomly from production, coded uniquely and allotted a reference number, which is quoted in every purchase order.

The QC sample is sent to QC laboratories for testing, the methodology of which is described below:

Master Batch (MB): Before the start of production of each lot of ZeroFly®, a five gram sample is extracted from both the ZeroFly® Low Density Polyethylene (LDPE) and the ZeroFly® High Density Polyethylene (HDPE) lots.

Central Weave (CW): Just after weaving, three samples of approximately 0.25 m² (50cm x 50cm) are taken each time after completion of approximately 10,000 square metres of fabric. The first sample is at least 100 metres from the beginning of the roll and the other two at random thereafter. All the samples must fall within two metre range on the roll.

Lamination/ finished product: After lamination, a full width sample of approximately two metres length is taken at the position where the CW samples were taken. This piece should contain both samples of the finished product and the lamination samples at the places where the CW samples were taken.

Coding/ labelling: Coding/ labelling of samples is done as per SOP S.01.

Dispatch of samples: Immediately after extracting the sample after lamination, all corresponding samples are packed independently and sent to the laboratory for analysis.

Handling of samples at the laboratory: Subsequently, the laboratory assigns parallel codes to the lamination and the finished product samples according to SOP S.01.

Reporting: Results of the chemical analysis from the laboratory are sent to Vestergaard Frandsen’s production database and if deviations from the specifications sheet occur, then the results are sent to the production manager.

Storage of samples: Reference samples are stored for a period of five years with full history at room temperature, for future reference.

Chemical analysis: Samples sent for chemical analysis are used to determine the pass/ fail status of the production. The methods analyse the total concentration of deltamethrin on the ZeroFly® tarpaulin. The method is described in the SOP.C.02.1.

Certificate of Quality

Each shipment of ZeroFly® plastic sheeting is accompanied with a Certificate of Quality (COQ). COQ summarises Quality Control testing data, including physical properties, chemical properties, dimension check, visual check, marking and packing for every batch or shipment.