The field test kit is sterilized prior to each use by removing the stainless steel flask from the funnel base assembly. This will wxpose an absorbent ring around the holder base. Set flame to the methanol on the absorbent ring. Make sure the entire ring is ignited. Place the filter cup, in an inverted position, over the funnel and the burning absorbent ring.
Sterilization is accomplished by formaldehyde produced by incomplete combustion of methanol.
Draw the syringe plunger slowly on the first stroke to avoid an air lock. Hold back on the plunger until the syringe fills. Push forward on the plunger to expel the filtered water from the syringe. Filter the sample, normally 100 ml through the monitor. Invert the assembly and use short quick strokes to pull any remaining water from the sample.