MW-RN-2020 (1)

Protocol for the Collection, Transfer and ANSI/AARST MW-RN 2020 Measurement of Radon in Water 9 5.5 Collection method 1—Bottle Use of appropriate supplies is required to collect and retain a representative sample. Water samples shall be collected in glass bottles. PTFE or aluminum-lined septum shall be required for the caps to eliminate loss of radon from the sample. An inverted septum will allow radon to emanate from the water sample and result in a low concentration of radon. The collector shall document the orientation of the lined septum on the bottle. Observance of an improper septum shall be recorded, and the sample voided. Note 1—Ring caps for the bottle with PTFE lined septa are recommended. When the bottle is completely filled, the septum will create a bulge in the cap interior. Note 2—Bottles made with low potassium glass will often produce a lower sample background. 5.5.1 Filled bowl or small bucket—Immersed bottle method For this method, the container is to be placed directly under the spigot (without aerator) and filled. Alternatively, the tubing and faucet adapters shown in Fig. 5.5.1-b ) are permitted to be used to fill a container (large bowl or small bucket) on condition that the tubing outlet is submerged under the water as soon as possible to minimize radon emanation from the water. The required collection procedures include discarding a sufficient volume of water to ensure that a representative sample is collected, and Steps 1-9 : (1) Slow the water flow to be non-turbulent and place the spigot (or tubing) under the surface of the water in the container as soon as possible to minimize radon emanation from the water ( Fig. 5.5.1-a ). Figure 5.5.1-a Filling the bowl or small bucket Submerged Spigot/Faucet