Numerical Advisory Solutions
Radiological Analysis

Radiological Analysis

NAS provides a wide range of radiological analysis capabilities including shielding, shine, dose, control room radiological and toxic gas habitability, and radiological equipment qualification. Additionally, our staff has extensive experience with source term calculations, on-site and off-site personnel dose analyses including post-accident dose maps, AST analyses, and hardened wet well vent analysis. As the developer and custodian of the Appendix B compliant RADTRAD-NAI code, NAS is uniquely qualified to address on-site and off-site dose analysis for our clients.

Analysis Division staff members have experience utilizing the following computer programs:
Alternative Source Term
NAS's experience supporting AST analysis includes application and the subsequent license amendment from source term, meteorological data development and supporting Requests for Additional Information (RAIs) from the NRC. NAS performs all required dose contributions defined in Regulatory Guide 1.183 including equipment shine, skyshine, operator transit dose, and Control Room, EAB and LPZ doses for thirty days for all licensing basis accidents.
Control Room Habitability
We provide control room habitability analysis ranging from toxic gas exposure to thirty-year integrated dose maps. Our staff has performed Control Room Habitability and infiltration evaluations and analysis, including hazardous chemical, radiological dose and temperature evaluations. In addition, we have provided designs for filtration, smoke, and CO2 venting systems.

Criticality Analysis
NAS has demonstrated experience performing criticality analysis and third-party reviews of criticality analyses for utilities. Staff experience with ORNL's SCALE package and MCNP specifically make NAS capable and qualified to assist with any criticality analysis needs.
Dose Analysis
With over 25 years of experience in on-site and off-site dose analysis, NAS has performed mission dose analyses, operability dose assessments, and shine dose calculations for containment, penetrations, and equipment.
RWST Back-Leakage Analysis
NAS provides a comprehensive evaluation of the potential back-leakage into the Refueling Water Storage Tank (RWST) and the implications on RWST pH and iodine re-evolution assure maximum benefit in dose margin.
Shielding Calculations
Shielding analysis can reduce necessary shielding materials and cost while meeting ALARA guidelines to protect operators and personnel. The staff at NAS is highly experienced in performing shielding calculations of varying complexity and ready to assist with all shielding analysis needs.