I have been tasked to calculate a Gross Bets DCGL for depleted uranium...my established Gross Alpah DCGL is 1250 dpm/100cm2....can anyone shed some light?
wail, da smartaze quickfire response wood be 3750 dpm/100 cm2 betagamma.
Quote from: SloGlo on Aug 17, 2007, 01:05
wail, da smartaze quickfire response wood be 3750 dpm/100 cm2 betagamma.
Yeah, 2.7 (or 3) beta to every anticipated alpha is a good thumb rule. But then again, it depends on the energy bata you are calibrated for.
The approach to the determination of site specific DCGLs, based on guidance contained in Preliminary Guidelines for Evaluating Dose Assessment in Support of Decommissioning" (NUREG-1549) is as follows:
• Step 1 – Determine the source inventory
• Step 2 – Define future land use scenarios
• Step 3 – Identify exposure pathways
• Step 4 – Develop conceptual model
• Step 5 – Determine DCGLs
• Step 6 – Perform sensitivity analysis
Beware of those quick answers, what scenario are you running? What effects does the local soil and water have on transport mechanisms? (you need to run a resrad determination.) If you are truely going to develop DCGL criteria- it may take you a while and then getting it justified will take longer. presentation to the stakeholders should be considered.
If you are developing scaling factors for surveys-develop your technical basis with instrument eff. for the energies of concern. That should only take a few days or week. Publish your technical basis and get it approved. If you are doing thumb rule frisking-(see first two replies) you are not developing a DCGL-you are making an operator aid. At that point each instrument will have a multiplier to compensate for the "number of clicks you hear" before you can release it. Technician review and some training should be provided.
Quote from: alphadude on Aug 21, 2007, 08:38
you need to run a resrad determination
And thats that bottom line.