Radon CRM Quality Assurance Program

I have a SunNuclear 1028 that is new to me, if fact radon testing in general is new to me. I have taken some training and trying to get my P’s & Q’s together before I start marketing this service.

I know that they need to be calibrated every 12 months. I also have read that they need to be cross checked every 6 months.

Can someone tell me what they do for cross checking when you only have one CRM? Any other info on a Quality Assurance plan for the testing device would be appreciated.

Thanks Guys/Girls

Buy some charcoal filter tests from Air Chek or similar company and run crm and charcoal tests at the same time to cross check