30 PGNAA Terms You Need to Know – Crossbelt or Onbelt?

SABIA works to ensure all our customers understand the necessary terminology for PGNAA Online, Crossbelt, or Onbelt analyzers.

Do you know all the lingo used around Online PGNAA Analyzers? What you need to know is that regardless your experience with Cement, Coal, Phosphate, Nickel, or other Minerals; this list will refresh you vocab, clarify a few terms, and help you make better decisions.



PGNAA – Prompt Gamma Neutron Activation Analysis: The technology SABIA Analyzers use. This nondestructive analysis method measures unique gamma rays to determine the elemental composition of bulk material moving on a conveyor belt or through a slurry pipe. learn more

Elemental Analysis: Determines a materials weight % composition of atom types (elements).

Near Real Time: PGNAA detects millions of gamma rays every second but due to the statistical nature of this technology analysis results are output every minute.

Californium – Cf-252: The neutron source for SABIA Analyzers. It is element 98 on the periodic table, the most reliable, cost effective, and safest neutron source available. read more

Neutron Generator: Create high energy neutrons that can be used for neutron activation analysis. Due to high energy levels additional shielding and barriers are generally required. read more

Neutron: A neutral atomic particle emitted from a neutron source. Neutrons bombard the material to be analyzed, which in turn emit gamma rays.

Gamma: After an atom is hit by a neutron it releases a gamma rays to stabilize. Gamma rays are unique to each element and counted to determine the elemental composition.

FPGA – Field Programmable Gate Array: Technology originally developed by the US military and used in drones. It is reliable and can withstand extreme conditions. SABIA Analyzers uses FPGA to ensure optimum performance in rugged industrial conditions.



On Line: The analyzer is installed directly in the path of the material flow. PGNAA continuously sees 100% of the material flow. Other online technologies may only analyze a portion of the material flow.

Cross Belt: Gamma-Metrics created the original cross-belt analyzer. It was installed on a support platform under the conveyor belt with the analyzer cross over the belt.

On Belt: SABIA created the original on-belt analyzer which is installed directly on conveyor stringers, hence on the belt. However, many people still reference this type of analyzer as a cross-belt analyzer.

Multiplexer: A piece of equipment used by older slurry analyzers which takes slurry samples for analysis. SABIA slurry analyzers do NOT require a multiplexer as the analyzer is installed directly around the main slurry line to provide a complete analysis of the slurry stream.

Shielding: Protects users from radiation. Proper shielding is regulated by government agencies and tests are always performed to ensure safe levels of radiation at all installations. See how SABIA shielding is configured in the video below:


Penetration: Dependent on the technology, how deep in the material analysis can be performed. PGNAA penetrates completely through the material, providing a full analysis. Without full penetration only a surface analysis is performed.

Signal: The gamma rays emitted from the material to be analyzed. More material creates a stronger signal and allows for greater accuracy.

Noise: The gamma rays emitted from the frame, shielding, belt, conveyor, etc. SABIA analyzers attenuate neutrons to produce less noise and improve accuracy.

% Spans: The amount of variation (max – min) for each element in a material being analyzed over time.

Cross Section: A numerical value correlating to the likelihood that an atom will absorb a neutron. Each element’s cross section determines how well it can be detected by PGNAA technology.

Measured Parameters: Actual elemental compositions (Si, Fe, P, S, etc). SABIA is the only company who can measure total moisture using PGNAA.

Calculated Parameters: Using elemental compositions to calculate things like Gross Calorific Value, Ash, C3S, LSF, Basicity, etc

Reference Standards: Used for static calibration of analyzers. These standards should cover the full range or % span of elements that will be seen by the analyzer. The can be made from site specific material or synthetically created in a lab.

Control Software: Uses analysis results to automatically make adjustments to equipment and change the material blend or other aspects.

Monitoring Software: Displays analysis results for a user who makes manual adjustments or control decisions.

Raw Mix Application: A blend of materials are on a belt. The blend is analyzed and results are used to make adjustments to source feeders in order to meet blend composition specifications. read more

Stockpile Application: Material is analyzed and piles are built based on analysis results. Tags are created for each layer to produce an accurate pile average for reclaiming. read more

Bituminous: Coal with high BTU and low Ash.

Lignite: Coal with low BUT and high Ash

HMI – Human Machine Interface: Where a user interacts with the analyzer for either control or data reporting. SABIA Analyzers have a user interface accessible from any web-enabled device connected to the site network. (also known as operator console, workstation, etc)

Belt Scale: Equipment installed on the conveyor to continuously measure the weight of material flowing on the belt (also known as a weigh scale). This required for PGNA Analysis and SABIA can accept weight signals via analog 4-20mA or digital TCP/IP.

VFD – Variable Frequency Drive: Equipment that changes the speed of the belt based on TPH to ensure a consistent material bed depth. While software can compensate for bed depth variations, PGNA Analyzers achieve optimum performance with a consistent bed depth.

Are there any other PGNAA terms you have questions about? Share this with your quality control colleagues so we all can speak the same language!

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