Lesson 9 How can you measure radon in water?

Slide 9-1 Radon in water Tap water from underground source may be a concern Test water to determine radon level Tap water from surface source usually not a concern

Slide 9-2 Risk from radon in water Radon released into the air Radon remaining in water

Slide 9-3 Result of radon in water Smoking increases the risk of lung cancer associated with radon

Slide 9-4 CT Department of Public Health Guidelines For private wells Mitigate if average (of 2 or more samples in 1 year) is 5,000 pCi/L or more

Slide 9-5 Taking a water sample Principles Sample carefully –Sample fresh water directly from well –Avoid exposure to open air when you collect and transport sample Analyze promptly –Ensure that the lab analyzes the sample within 4-6 hours of its collection –Use a lab approved by the Connecticut Department of Public Health LABLIST.pdf

Slide 9-6 Sampling methods Direct syringe Filled vial

Slide 9-7 Preparation for both methods Remove aerator if present Select a sample point before water passes through any water treatment device –Example: Outside hose connection Run cold water from faucet for enough time to collect water directly from the well –Usually about minutes –Discard water that has been sitting in well casing, pipes, or pressure tank Sample before Hot water heater Water softener Holding tank

Slide 9-8 Direct syringe method Equipment –A 10 cm 3 syringe –2 glass vials containing mineral oil Radon dissolves in mineral oil, which prevents gas from escaping into air in the vial

Slide 9-9 Direct syringe procedure Use a short hose to connect a funnel to faucet Run water to fill the hose and overflow funnel Insert syringe below water surface in funnel Collect a 10 cm 3 sample Place syringe tip below mineral oil and gently inject sample into vial Repeat, taking second sample from same source

Slide 9-10 Filled vial method Equipment –2 40 mL glass vials with screw caps that seal tightly Procedures –Be careful to avoid air bubbles –Fill vials using procedure A or B

Slide 9-11 Filled vial procedures Procedure A Fill vial very slowly from faucet Allow vial to overflow Cap quickly Repeat with another vial –Take second sample from same source Procedure B Hold bowl close to faucet and run water until bowl overflows Submerge vial in bowl and cap vial while water is running Repeat with another vial –Take second sample from same source

Slide 9-12 After collection Check for air bubbles –Turn vials upside downs –If you see bubbles, repeat collection procedure until sample contains no bubbles Record –Volume –Date and time of collection Pack vials carefully Mail to lab the same day –Send via quick method so samples arrive within 3 days –Lab should analyze samples the same day they arrive

Slide 9-13 Pros and cons Direct syringe Pro More accurate Con May be difficult to ship Filled vial Con Requires great care to avoid bubbles Pro Easier to ship

Slide 9-14 Questions?

Slide 9-15 Summary Underground water sources may contain dangerous levels of radon Radon can cause lung, stomach, and other cancers CT DPH guidelines: mitigate if average level is 5,000 pCi/L or more

Slide 9-16 Summary Principles of taking water samples 1.Sample carefully Get fresh water direct from well Avoid exposing sample to air 2.Analyze samples promptly

Slide 9-17 Summary Direct syringe method Filled vial