Start with the measurement
Dose-rate meters assess a radiation field; personal dosimeters track a wearer’s accumulated dose; surface-contamination instruments assess radioactive material on surfaces. These are different purchasing requirements. Specify the measurement quantity and radiation type for each task before combining products in one package.
Official references: IAEA — Instrumentation in Operational Radiation Protection
Compare like-for-like specifications
Build a table for the proposed model and probe: radiation type, measurement quantity, units, range, energy response, response time and operating conditions. Add weight, screen readability, battery arrangement and data export. Ask suppliers to identify which functions are included and which require an optional probe or software licence.
Keep units and evidence together
Dose is often expressed in µSv or mSv, while dose rate uses units such as µSv/h. A contamination reading may be a count rate or a calibrated activity measurement. Retain the unit, detector and calibration basis with each specification; a larger number on a different scale does not establish better performance.
Official references: IAEA — Workplace Monitoring, Practical Radiation Technical Manual
Make the quotation complete
Send the intended workplace, monitoring task, required records, quantity and destination. Request model-specific documentation, probe references, calibration scope, accessories, warranty and service arrangements. Include a sample data export and an agreed acceptance checklist where reporting is part of the purchase. Let your radiation-protection lead confirm the final measurement requirements.