• MA: Direct thermal decomposition mercury analyzer
  • PE: Fully automated petro-pyrolysis mercury analyzer
  • RA: Reducing-vaporization mercury analyzer
  • RA-4500
  • RA-4300
  • RA-4300FG+
  • RA-5A
  • WA: Atmospheric mercury analyzer
  • EMP: Portable mercury survey meter

[Proffessional point of view] How to select the best mercury analyzer?
[select application/method to] Search the best mercury analyzer

Reducing-vaporization mercury analyzer


Reducing-vaporization CVAFS mercury analyzer with a built-in activated carbon filter, complies with global standards



Built-in activated carbon filter unit fr reducing external mercury influence

The RA-4300FG+ is reducing-vaporization mercury analyzer with ultra-high sensitivity that complies with global standards. This equipment uses gold amalgamation and atomic fluorescence spectroscopy.


The equipped activated carbon filter unit lowers mercury concentration of air inside the equipment, by which, external mercury influence, which poses a problem when analyzing mercury in the low concentration range, is reduced in the working environment. Additionally, reagents are purged by argon gas containing no mercury to minimize the reagent blank increase during analysis.

The RA-4300FG+ is equipped with evaluation software according to EPA1631E which specifies the gold amalgamation method, and to EPA245.7 which specifies the direct reducing-vaporization method so that you can confirm the reliability of the measurement.

Measurement principle

By adding the reducing solution (Tin (II) Chloride) to the divalent mercury ion (Hg2+) in the sample solution, mercury is reduced into zero-valent atomic mercury. Then, by flowing gas, mercury is turned into vapor. Moisture is removed into the Nafion tube. The atomic mercury is concentrated as gold amalgam by the use of a gold-supported collector tube. After all mercury in the liquid sample is concentrated, the collector tube is heated to liberate mercury as atomic mercury which is sent to the detector. For detection, atomic fluorescence spectroscopy is used to perform highly sensitive mercury concentration measurement.

Pretreatment method


Bromine monochloride is dropped into the sample to decompose organic substances. Next, hydroxylammonium chloride solution is added to mask bromine chloride that obstructs mercury measurement. Then, Tin (II) Chloride solution is added.


This is a method to directly measure mercury after the pretreatment above without concentrating it in the collector tube.

Alkali reduction method

Sodium hydroxide solution and copper sulfate solution are added to the sample, and then Tin (II) Chloride solution is added. Total mercury can be easily measured.

Other methods

You have other measurement options, including measurement that uses only sulfuric acid and Tin (II) Chloride solution without decomposing organic substances in the sample, or measurement that uses hydroxylammonium chloride solution and Tin (II) Chloride solution (gold amalgamation) after decomposing organic substances.


Sample treatment sectionNumber of sample80
Drive systemTurn table system
Sample trayPolycarbonate
Sample containerDisposable glass tube
BubblerReagent-resistance resin bubbler
Reagent dispenser sectionDispensingDelivered with a tube pump
Dispensing volumeAdjustable
Dispensed reagentsBrCl or Sulfuric acid, Tin (II) chloride solution, Hydroxylamine hydrochloride solution, Distilled water
Mercury detecting sectionMeasurement principleCold vapor Atomic Fluorescence Spectroscopy
Measurement methodReducing vaporization with open air-supply
(Peak height measuring and integration measuring selectable)
Light sourceLow pressure mercury discharge lamp
Wave length253.7nm
Detection limit0.25pg/5mL (0.05ppt)
*0.5ppt in case of including EPA1631e digestion
Maximum range1,000ng/5mL (200ppb)
Measuring time90sec~300sec
Mercury removalAbsorption by activated carbon
Flow monitorFlow sensor
Data processing system
OSWindows 10 Pro
CommunicationEthernet (One-to-one for RA-4300, not for in-house LAN)
DisplayPeak wave shape, Calibration curve, Measuring time and Measuring result
Control softwareStart/stop measuring: Controllable, Reagent dispensing volume setup
Data processing softwareEPA criteria report
Selectable from 6 formulas (3 linear and 3 3rd Order fits), Correlation coefficient is automatically calculated.
Statistic calculation: Mean value, Standard deviation, Coefficient of variation (All values are automatically calculated.)
PrintMeasuring conditions, Calibration curve, Measured values, Statistical calculations, Peak wave shape and Measuring time
Quality controlCheck standard, Avoid abnormally high mercury etc.
Installation requirementsInstallation dimensions 580W x 530D x 753H (mm)  *With air clean unit
Power supply(1) AC, single phase, 100V, 220~240V 50/60Hz
(2) Voltage variation: within ±5%
(3) Power capacity: 0.24 kVA (Excluding PC and printer)
(4) Power quality: Non surging, no high-frequency waves, and noiseless.
(5) Distance from power supply: 2m or less
(6) Ground-fault circuit interrupter: 15mA
(7) Grounding: Grounding terminal with ground resistance of 100Ω or less


Drinking water, Underground water, Seawater, Wastewater, River water, Lake water, Rain-runoff, Liquid & Solid Digestates and more

Test methods

USEPA 245.7; 1631e; ISO 17852; ISO12846


No special options available.

Page Top