ISO 16640 Monitoring of Radioactive Gases in Waste Waters from Facilities Producing Positron-Emitting Radionuclides and Radiopharmaceuticals

The standard “ISO 16640 Monitoring of radioactive gases in wastewater from facilities producing positron-emitting radionuclides and radiopharmaceuticals” developed by the International Organization for Standardization (ISO) focuses on monitoring the activity concentrations of radioactive gases. This standard allows the calculation of activity releases in gaseous wastewater discharges from facilities producing positron-emitting radionuclides and radiopharmaceuticals. Such facilities produce short-lived radionuclides used for medical purposes or research and can typically release gases including, but not limited to, fluorine, carbon, oxygen, and nitrogen. These facilities include accelerators, radiopharmaceuticals, hospitals, and universities.

This standard provides performance-based criteria for the design and use of air monitoring equipment, including probes, conveying lines, sample monitoring devices, and gas flow measurement methods. The standard also provides information on monitoring program objectives, quality assurance, development of air monitoring control action levels, system optimization, and system performance verification.

The goal of obtaining an unbiased measurement is achieved by direct (in-line) measurement in the exhaust stream or by sampling from the exhaust stream (bypass), provided that the radioactive gases are well mixed in the air stream. This standard sets out performance criteria and recommendations to assist in obtaining valid measurements.

The criteria and recommendations of this standard are intended to monitor for regulatory compliance and system control. If existing air monitoring systems are not designed in accordance with the performance criteria and recommendations of this standard, it is recommended that the performance of the system be evaluated. If deficiencies are identified based on a performance evaluation, the need for system improvement should be determined and corrective actions adopted where applicable.

The criteria and recommendations of this standard are valid under both normal and abnormal operating conditions, provided that these conditions do not involve the production of aerosols or vapours. If normal or abnormal conditions produce aerosols and vapours, the aerosol collection principles of ISO 2889 apply.

For the purposes of this standard, the following terms and definitions apply:

• Abatement equipment is apparatus used to reduce the concentration of pollutants in an air stream exhausted from a chimney or duct.
• Accident (circumstances) refers to any unexpected event, including operating errors, equipment failures and other mishaps, the consequences or potential consequences of which cannot be neglected from the perspective of protection and safety.
• Accuracy is the closeness of agreement between a measured quantity and the true quantity of the measurand.
• The action level is the threshold concentration of a waste pollutant at which appropriate action is required.
• An aerosol is a dispersion of solid or liquid particles in air or other gas. An aerosol is not just aerosol particles.
• An analyzer is a device that provides near real-time data on the radiological properties of a gas (air) stream in a sampling system or duct. Typically, an analyzer evaluates the concentration of radionuclides in a sampled air stream, but some analyzers are mounted directly in or just outside a chimney or duct.
• Bending is the gradual change in direction of a sample conveying line.
• Mass flow is the air flow in a stack or duct (as opposed to sample flow rate).
• A bypass system is one in which a sample is withdrawn from the wastewater stream and analyzed at a location remote from where the extraction occurs.
• Calibration is the process of first establishing a relationship between quantity values ​​with measurement uncertainties provided by measurement standards and corresponding indicators with associated measurement uncertainties, under specified conditions, and in a second step using this information to establish a relationship between an indicator and a measurement result.
• A radionuclide is an unstable isotope of an element that spontaneously decays or transforms into another isotope or a different energy state, emitting radiation.

Positron emitting radionuclides are increasingly used in medical diagnostics and the number of radiopharmaceutical production facilities is increasing. During the production or patient administration of radiopharmaceuticals, some of these radionuclides may become airborne and escape into the environment. Therefore, analysis of radionuclide concentration in released air is a very important issue to assess the dose to the population living in the vicinity of the facility.

Among the numerous testing, measurement, analysis and evaluation studies that our organization has carried out for businesses in various sectors, our organization also provides certification and testing services defined in the standard “Monitoring of radioactive gases in wastewater from facilities producing positron emitting radionuclides and radiopharmaceuticals” with its trained and expert staff and advanced technological equipment.