Who owns RKI Instruments, where is RKI located, where are RKI gas monitors made, and what happened to the Eagle 2 and GX-6000?
RKI Instruments, Inc. is the North American partner of Riken Keiki Company, Ltd. of Japan: RKI’s own About page states it is partnered with Riken Keiki, was founded in 1994, and is the exclusive North American supplier of Riken products. It is headquartered at 33248 Central Avenue, Union City, California, with a Gulf Coast office and training center in Deer Park, Texas. The monitors on this site are listed in RKI’s product data file with Japan as the country of origin. RKI describes itself as an ISO 9001 company and prints a CSA certificate of compliance on its site. Its current portable line is the GX-3R (4-gas), GX-3R Pro (1 to 5 gas), GX-Force (1 to 4 gas with a pump), GX-6100 (up to 6 gas with PID) and the 04 Series single-gas units; RKI lists the Eagle 2 as “Eagle 2 (discontinued product)” with the Eagle 3 marked coming soon, and the GX-6000 as “GX-6000 (discontinued)” with the statement that the GX-6100 is its next-generation replacement. RKI’s site does not spell out what the letters RKI stand for.
RKI Instruments 72-RA-E GX-3R 4-Gas Monitor, LEL/O2/H2S/CO, No ChargerThe GX-3R, which RKI calls the world’s smallest 4-gas monitor (RKI data)Why the company questions come up with the product questions. A buyer comparing a GX-3R Pro with an ALTAIR or a Ventis wants to know who stands behind it, where the warranty is honored and whether the instrument on the shelf is current. RKI’s answers are on its own pages. The partnership with Riken Keiki goes back to 1994 and the GX-94 four-gas monitor; Riken’s history, as RKI tells it, runs from the first catalytic combustible monitors in 1938 through the first three-gas monitor with alarm in 1978, the first belt-worn four-gas monitor (GX-86) in 1986, and the first six-gas portable, the EAGLE, developed with RKI in 1995. The portable line turned over in the last few years: the GX-3R replaced the GX-2009, the GX-3R Pro and GX-Force arrived with the R-series micro-sensors, the GX-6100 replaced the GX-6000, and the Eagle 2 is discontinued ahead of the Eagle 3. The sensors, filters, calibration kits and parts for the discontinued instruments stay in RKI’s parts list and on this site.
The company facts, with RKI’s source for each
The RKI portable line today, as RKI describes it
From RKI's product pages, About page and FAQ:
- GX-3R: the world's smallest 4-gas monitor by RKI's description, 3.52 oz, LEL, O2, H2S and CO from three sensor slots, 25 hours Li-ion, IP-66/68, ATEX, CSA, IECEx, MED, 3-year warranty.
- GX-3R Pro: 1 to 5 gases, 4.58 oz, a fourth slot for HCN, NH3, NO2, PH3, SO2 or infrared CO2, Bluetooth to the RK Link app, man-down alarm, Li-ion or alkaline.
- GX-Force: 1 to 4 gases with an internal pump and a 100 ft sample range, 9.87 oz, 30 hours Li-ion, USB Type-C, Leak Check mode, IECEx, ATEX, QPS Class I Division 1 and Class I Zone 0.
- 04 Series: single-gas monitors (two gases in the CX-04) on two AAA batteries, 3,000 to 9,000 hours of continuous operation, IP-67, intrinsically safe to ATEX/IECEx and QPS Class I Division 1.
- GX-6100: up to six gases with PID, infrared and toxic sensors, combustibles in ppm, percent LEL and percent volume, 28 hours, Bluetooth; the replacement for the GX-6000 (not stocked on this site at the time of writing).
- Calibration stations SDM-3R and SDM-Force, the RP-3R clip-on pump, 34 to 116 L calibration kits, and fixed systems (Beacon controllers, M2A and S2 detector heads, AirLink wireless, the Digester Gas Monitor) that RKI lists for its industries.
- Warranty across the portable line: three years on material and workmanship including sensors; one year for the ammonia and chlorine sensors and the PID; shelf life on calibration gas is RKI's warranty on the cylinder.
- Service: RKI's FAQ describes sensor date codes (first two serial-number characters: year, then month 1 to 9, X, Y, Z), a service and repair form, and technician training classes in Deer Park.
RKI run times and sampling, as printed
| Model | Gases | Sampling | Power and run time | Weight | Ingress rating | Approvals |
|---|---|---|---|---|---|---|
| GX-3R Pro | 1 to 5 (LEL, O2, H2S, CO plus one toxic or IR) | Diffusion (RP-3R pump optional) | Li-ion 25 h or alkaline 16 h with an EC fifth sensor; 16 h / 7 h with the IR CO2 sensor | 4.58 oz | IP-66/68 | ATEX, CSA, IECEx, MED |
| GX-3R | 4 (LEL, O2, H2S, CO) | Diffusion (RP-3R pump optional) | Li-ion, approx. 25 h after a 3 h charge | 3.52 oz | IP-66/68 | ATEX, CSA, IECEx, MED |
| GX-Force | 1 to 4 (LEL, O2, H2S, CO) | Internal pump, 100 ft sample range, 0.5 L/min | Li-ion, approx. 30 h; USB Type-C | 9.87 oz | IP67 equivalent | IECEx, ATEX, C QPS US Class I Div 1 Groups A, B, C, D; Class I Zone 0 |
| 04 Series (HS-04, CO-04, CO-04C, OX-04, CX-04, SC-04) | 1 (2 for the CX-04) | Diffusion | 2 AAA alkaline; 9,000 h HS-04 and CO-04, 6,200 h CO-04C, 3,000 h OX-04 and SC-04, 4,600 h CX-04 | 2.8 oz | IP-67 | ATEX, IECEx, QPS C/US Class I Div 1 Groups A, B, C, D |
Source: RKI Instruments GX-3R Pro product page and specification table (rkiinstruments.com/product/gx-3r-pro-gas-detector, rkiinstruments.com, fetched Nov 8 2026); RKI Instruments GX-3R product page and specification table (rkiinstruments.com/product/gx-3r-gas-detector, rkiinstruments.com, fetched Nov 8 2026); RKI Instruments GX-Force product page and specification table (rkiinstruments.com/product/gx-force-portable-4-gas-monitor, rkiinstruments.com, fetched Nov 8 2026); RKI Instruments 04 Series product page and specification table (rkiinstruments.com/product/04-series-single-gas-detectors, rkiinstruments.com, fetched Nov 8 2026)
Questions people ask
Who owns RKI instruments?
RKI Instruments, Inc. is the North American partner of Riken Keiki Company, Ltd. of Japan: RKI’s About page states it is partnered with Riken Keiki, was founded in 1994 and is the exclusive North American supplier of Riken products.
Where is RKI Instruments located?
33248 Central Avenue, Union City, California, with a Gulf Coast office and training center in Deer Park, Texas, by RKI’s pages.
Is the RKI Eagle a PID?
The Eagle 2 could carry a PID sensor among its up to six gases, but it is listed by RKI as “Eagle 2 (discontinued product)” with the Eagle 3 marked coming soon. RKI’s current PID instrument is the GX-6100, which keeps the GX-6000’s 10.0, 10.6 and 11.7 eV lamps, Benzene Mode and smart sensor slots; its configurations are in the band on this page.
What is a RKI GX 6000?
A six-gas pumped monitor with up to two PID sensors that RKI now lists as “GX-6000 (discontinued)”; RKI states the GX-6100 is its next-generation replacement with the same PID lamps and modes, up to 28 hours of run time against 14 and Bluetooth added. The GX-6000’s sensors and parts remain available.
What is an RKI?
An RKI gas monitor: a portable or fixed gas detector from RKI Instruments. The trade uses the brand name for the instrument the way it uses MSA or BW.
What is GX force?
RKI’s GX-Force is a 1- to 4-gas portable monitor with an internal sample pump and a 100 ft sampling range, 9.87 ounces, about 30 hours on Li-ion, USB Type-C, a Leak Check mode reading combustibles in ppm, and IECEx, ATEX and QPS Class I Division 1 approvals, by RKI’s product page.
Where can I find the operator’s manual for the RKI GX-6000 gas monitor?
RKI’s GX-6000 product page keeps its documents, including the operator’s manual, under the discontinued notice; the GX-6100 page carries the current manual, datasheet, quick reference card and PID response chart, which the GX-6100 product pages on this site link.
What is the price of the RKI Eagle 2?
RKI has discontinued the Eagle 2 and it is no longer listed on this site; the GX-6100 configurations in the band show the prices of RKI’s current six-gas pumped monitors.
What does RKI stand for?
Riken Keiki Instruments, after the Japanese parent Riken Keiki Company, Ltd.
What is the warranty on RKI gas detectors?
Three years on material and workmanship including sensors across the portable line; one year for the ammonia and chlorine sensors and the PID, two years for the GX-6100’s infrared sensors, by RKI’s pages.
Where are RKI gas monitors made?
Japan, by the country of origin in RKI’s product data file carried on each product page.
The ratings, test results and standards shown here are the manufacturers' published values, reproduced as published. Nothing on this page is a recommendation by Bayshore Safety that any product is suitable for a particular task, hazard or workplace. Selecting safety products and protective equipment is the responsibility of the end user and the employer, based on their own hazard assessment and the regulations that apply to their work. Confirm every value on the manufacturer's own documentation before use.