PT0E-09813

Portable Gas Monitor

GX-8000
Operating Manual(PT0-098)

<Contents>
1. Outline of the Product........................................................................................................... 3
1-1. Preface ........................................................................................................................... 3
1-2. Purpose of use ............................................................................................................... 3
1-3. Definition of DANGER, WARNING, CAUTION, and NOTE ............................................ 3
1-4. Method of confirmation for Standards and Explosion proof specification ....................... 4
2. Important Notices on Safety ................................................................................................. 5
2-1. Danger cases ................................................................................................................. 5
2-2. Warning cases ................................................................................................................ 8
2-3. Precautions .................................................................................................................... 9
2-4. Safety information .......................................................................................................... 11
3. Product Components ............................................................................................................ 12
3-1. Main unit and standard accessories ............................................................................... 12
3-2. Names and functions for each part ................................................................................. 15
4. How to Use ........................................................................................................................... 18
4-1. Before using the gas monitor.......................................................................................... 18
4-2. Preparation for start-up................................................................................................... 18
4-3. Basic operating procedures ............................................................................................ 23
4-4. How to start the gas monitor........................................................................................... 24
4-5. How to detect ................................................................................................................. 26
4-6. Modes ............................................................................................................................ 30
4-7. Air calibration mode ........................................................................................................ 31
4-8. Display/setting mode ...................................................................................................... 33
4-9. How to exit...................................................................................................................... 40
5. Operations and Functions .................................................................................................... 41
5-1. Gas alarm activation ....................................................................................................... 41
5-2. Fault alarm activation ..................................................................................................... 43
5-3. Other functions ............................................................................................................... 43
6. Maintenance ......................................................................................................................... 44
6-1. Maintenance intervals and items .................................................................................... 44
6-2. Gas calibration method .................................................................................................. 45
6-3. How to clean................................................................................................................... 46
6-4. Parts replacement .......................................................................................................... 46
7. Storage and Disposal ........................................................................................................... 49
7-1. Procedures to store the gas monitor or leave it for a long time ...................................... 49
7-2. Procedures to use the gas monitor again ....................................................................... 49
7-3. Disposal of products ....................................................................................................... 50
8. Troubleshooting .................................................................................................................... 51
9. Product Specifications .......................................................................................................... 53
9-1. List of specifications ....................................................................................................... 53
9-2. List of accessories .......................................................................................................... 55
10. Definition of Terms .............................................................................................................. 56

2

1

Outline of the Product1-1. Preface
Thank you for choosing our portable gas monitor GX-8000. Please check that the model number of the
product you purchased is included in the specifications on this manual.
This manual explains how to use the gas monitor and its specifications. It contains information required forusing the gas monitor properly. Not only the first-time users but also the users who have already used the
product must read and understand the operating manual to enhance the knowledge and experience before
using the gas monitor.
Product specifications may be abbreviated in this document as follows.
Japan Ex specification ： Japan specification
ATEX / IECEx specification ： Export specification

1-2. Purpose of use
This gas monitor is a multi gas type that enables simultaneous monitoring of all of the following five types ofgases at the maximum: oxygen, combustible gases, and toxic gases (carbon monoxide and hydrogensulfide) in the air and high-concentration combustible gases (vol%) in N2 and inert gases.
Detection results are not intended to guarantee life or safety in any way.
The gas monitor comes in several types for different combinations of gases to be detected. Check the
specifications of the gas monitor before use and conduct gas detection properly in accordance withpurposes. (See the list of gases to be detected at the end of this operating manual.)
In addition to this operating manual, an operating manual for the data logger management program (option)
is available for the gas monitor. Contact RIKEN KEIKI if it is needed.

1-3. Definition of DANGER, WARNING, CAUTION, andNOTE
DANGER

This message indicates that improper handling may cause serious damage on
life, health or assets.

WARNING

This message indicates that improper handling may cause serious damage on
health or assets.

CAUTION

This message indicates that improper handling may cause minor damage on
health or assets.

NOTE

This message indicates advice on handling.

31-4. Method of confirmation for Standards andExplosion proof specification
This instrument has some specification depends on standard and explosion proof certificate. Pleaseconfirm the detector specification before using. Please refer Declaration of Conformity that is at the end of
this manual if you have CE marking type. You can confirm instrument specification to see name plate as
follows.
Japan Ex certificate

Main unit

Main unit

Ex marking
CE marking
Battery unit

Battery unit

Japan Ex type name plate

ATEX/IECEx, CE marking type name plate4

2

Important Notices on
Safety2-1. Danger cases
DANGER
Nameplate location
Main unit

Battery unit

About explosion-proof of main unit Do not modify or change the circuit or structure, etc.
 When measuring the oxygen concentration, do not measure anything but a mixture of air andcombustible gases or vapors and toxic gases.
 When using this gas monitor in a hazardous area, take the following countermeasures forpreventing dangers resulting from electrostatic charges.
(1) Wear anti-static clothes and conductive shoes (anti-static work shoes).
(2) For indoor use, use the gas monitor while standing on a conductive work floor (with aleakage resistance of 10 MΩ or less).
 The battery unit that can be connected vary according to Explosion-proof approval No. of mainunit.

Model/Explosion-proof approval No.
of main unit

Model/Explosion-proof approval No.
of battery unit that can be connected

GX-8000 / TC19439

BUL-8000(G) / TC19437
BUD-8000(G) / TC19438

GX-8000 / TC21222

BUL-8000(G1) / TC21223
BUD-8000(G1) / TC21224

5

DANGER The specifications of main units are as follows:
Pump circuit:
Allowable voltage of 4.95 V, allowable current of 1.12 A, andallowable power of 1138 mW
Combustible gas sensor circuit: Allowable voltage of 4.95 V, allowable current of 0.834 A, andallowable power of 853 mW
Buzzer circuit:
Allowable voltage of 4.95 V, allowable current of 0.431 A, andallowable power of 441 mW
Main circuit:
Allowable voltage of 4.95 V, allowable current of 0.717 A, andallowable power of 733 mW
Backup circuit:
3.0 VDC, 10 µA
Ambient temperature:-20 °C to +50 °C
 Explosion-proof grade of main unit is Ex ia ⅡC T4 X.
About explosion-proof of battery unit Do not modify or change the circuit or structure, etc.
 When using this gas monitor in a hazardous area, take the following countermeasures forpreventing dangers resulting from electrostatic charges.
(1) Wear anti-static clothes and conductive shoes (anti-static work shoes).
(2) For indoor use, use the gas monitor while standing on a conductive work floor (with aleakage resistance of 10 MΩ or less).
 The main unit that can be connected vary according to Explosion-proof approval No. of battery
unit.

Model/Explosion-proof approval No.
of battery unit

Model/Explosion-proof approval No.
of main unit that can be connected

BUL-8000(G) / TC19437
BUD-8000(G) / TC19438

GX-8000 / TC19439

BUL-8000(G1) / TC21223
BUD-8000(G1) / TC21224

GX-8000 / TC21222

 The specifications of lithium ion battery units are as follows:
Pump circuit:
Maximum voltage of 4.25 V, maximum current of 1.12 A, andmaximum power of 901 mW
Combustible gas sensor circuit: Maximum voltage of 4.25 V, maximum current of 0.768 A, andmaximum power of 618 mW
Buzzer circuit:
Maximum voltage of 4.25 V, maximum current of 0.410 A, andmaximum power of 330 mW
Main circuit:
Maximum voltage of 4.25 V, maximum current of 0.653 A, andmaximum power of 526 mW
Battery charging contact:
Allowable current of 250 VAC 50/60Hz
Ambient temperature:-20 °C to +50 °C
 Explosion-proof grade of lithium ion battery units are Ex ia ⅡC T4.

 The specifications of dry battery units are as follows:
Pump circuit:

Maximum voltage of 4.95 V, maximum current of 1.12 A, andmaximum power of 1138 mW
Combustible gas sensor circuit: Maximum voltage of 4.95 V, maximum current of 0.834 A, andmaximum power of 853 mW
Buzzer circuit:
Maximum voltage of 4.95 V, maximum current of 0.431 A, andmaximum power of 441 mW
Main circuit:
Maximum voltage of 4.95 V, maximum current of 0.717 A, andmaximum power of 733 mW
Power supply:
4.5 VDC, 250 mA (Type LR6 manufactured by Toshiba, 3 pcs)
Ambient temperature:-20 °C to +50 °C
 Explosion-proof grade of dry battery units are Ex ia ⅡC T4.

6

DANGER
About combination
Make sure that the product model on the nameplate and combination of main unit and battery unit
is correct.
Inappropriate combinations of models deviate from the range of explosion-proof certification.
 IP protection class: IP20



About use While conducting measurement in a manhole or confined space, do not lean over or look into the
manhole or closed space. It may lead to dangers because oxygen-deficient air or other gases
may blow out.
 Oxygen-deficient air or other gases may blow out from the gas exhausting outlet. Never inhale
the air or gases.
 High-concentration (more than LEL) gases may blow out. Never use fire near the gas monitor.

7

2-2. Warning cases
WARNING
Sampling point pressure The gas monitor is designed to draw gases around it under the atmospheric pressure. If
excessive pressure is applied to the gas inlet and outlet (GAS IN, GAS OUT) of the gas monitor,
detected gases may be leaked from its inside, thus leading to dangers. Be sure that excessive
pressure is not applied to the gas monitor while used.
 Do not connect the gas sampling hose directly to a location with a pressure higher than theatmospheric pressure. The internal piping system may be damaged.
Handling of sensor
Do not disassemble the electrochemical type sensor or galvanic cell type sensor because they
contain electrolyte. Electrolyte may cause severe skin burns if it contacts skin, while it may cause
blindness if it contacts eyes.
If electrolyte is adhered on your clothes, that part on your clothes is discolored or its material isdecomposed. If contact occurs, rinse the area immediately with a large quantity of water.
Fresh air adjustment in atmosphere
When the fresh air adjustment is performed in the atmosphere, check the atmosphere for freshness
before beginning the adjustment. If other gases exist, the adjustment cannot be performed properly,
thus leading to dangers when the gas leaks.
Response to gas alarm
Issuance of a gas alarm indicates that there are extreme dangers. Take proper actions based onyour judgment.
Battery level check Before use, check that there remains sufficient battery power. When the gas monitor is used forthe first time or is not used for a long period, the batteries may be exhausted. Either fullyrecharge the batteries or replace them with new ones before use.
 If a low battery voltage alarm occurs, gas detection cannot be conducted. If the alarm occurs
during use, turn off the power and promptly recharge the batteries in a non-hazardous area.
Others Do not throw the gas monitor into fire.
 Do not wash the gas monitor in a washing machine or ultrasonic cleaner.
 Do not block the buzzer sound opening. No alarm sound can be heard.
 Do not remove the battery unit while the power is ON.

82-3. Precautions
CAUTION
Do not use the gas monitor where it is exposed to oil, chemicals, etc. Do not submerge the gas
monitor under water on purpose.
 Do not use in a place where the gas monitor is exposed to liquids such as oil and chemicals.
 The gas monitor, being compliant to IP67, is not water-pressure-resistant. Do not use the gas
monitor where a high water pressure is applied to it (under a faucet, shower, etc.) or submerge it
under water for a long time. The gas monitor is water-proof only in fresh water and runningwater, and not in hot water, salt water, detergent, chemicals, human sweat, etc.
 The gas inlet and outlet are not water-proof. Be careful not to let water such as rainwater get into
these parts. Because this may cause trouble and gas cannot be detected.
 Do not use the gas monitor where water or dirt gets accumulated. The gas monitor placed atsuch a location may malfunction due to water or dirt that gets into the buzzer opening, gas inlet,etc.
 Note that drawing in dirty water, dust, metallic powder, etc. will significantly deteriorate thesensor sensitivities. Be careful when the gas monitor is used in an environment where theseelements exist.
Do not use the gas monitor in a place where the temperature drops below -20 °C or rises over 50 °C.
 The operating temperature of the gas monitor is -20 °C to +50 °C. Do not use the gas monitor at
higher temperatures, humidities, and pressures or at lower temperatures than the operating
range.
 Avoid long-term use of the gas monitor in a place where it is exposed to direct sunlight.
 Do not store the gas monitor in a sun-heated car.
Observe the operating restrictions to prevent condensation inside the gas monitor or gas sampling
hose.
Condensation formed inside the gas monitor or gas sampling hose causes clogging or gas
adsorption, which may disturb accurate gas detection. Thus, condensation must be avoided. In
addition to the operating environment, carefully monitor the temperature/humidity of the sampling
point to prevent condensation inside the gas monitor or gas sampling hose. Please observe theoperating restrictions.
Do not use a transceiver near the gas monitor.
 Radio wave from a transceiver near the gas monitor may disturb readings. If a transceiver isused, it must be used in a place where it disturbs nothing.
 Do not use the gas monitor near a device that emits strong electromagnetic waves(high-frequency or high-voltage devices).
Verify that the pump driving indicator is rotating before using the gas monitor.
If the pump driving indicator is not rotating, gas detection cannot be performed properly. Check
whether the flow rate is lost.
Do not forget to perform a regular maintenance.
Since this is a safety unit, a regular maintenance must be performed to ensure safety. Continuing to
use the gas monitor without performing a maintenance will compromise the sensitivity of the sensor,
thus resulting in inaccurate gas detection.

9

CAUTION
Others Pressing buttons unnecessarily may change the settings, preventing alarms from activatingcorrectly. Operate the gas monitor using only the procedures described in this operating manual.
 Do not drop or give shock to the gas monitor. The water-proof and explosion-proof properties
and accuracy may be deteriorated.
 Do not use the gas monitor while recharging it.
 Whereas the gas monitor can detect oxygen, combustible gases, carbon monoxide, andhydrogen sulfide, the operating environment may include gases that have harmful effects on thesensors of this unit. (Different gases can be defected depending on the type.)
The gas monitor cannot be used in the presence of the following gases:(1) Sulfides (such as H2S and SO2) continuously existing in high concentrations(2) Halogen gases (such as chloride compounds and chlorofluorocarbons)(3) Silicone (Si compounds)
Do not use the gas monitor in the presence of the above gases (such as high-concentration
sulfides, halogen gases, and silicone), which may shorten the sensor life significantly or cause
malfunctions such as inaccurate readings.
In case the gas monitor is used for detection in the presence of silicone, etc., be sure to checkthe gas sensitivities before using it again.

10

2-4. Safety information
The Portable Gas Monitor Model GX-8000 is a gas monitor designed to provide continuous exposure
monitoring of combustible gas, oxygen (O2), toxic gas such as carbon monoxide (CO) and hydrogen sulfide(H2S) in hazardous environments. The gas sample is sucked in by build-in micro pump.
The battery can be selected either Li-ion battery or alkaline dry battery.
Li-ion battery unit is called BUL-8000,BUL-8000(G),BUL-8000(G1) and alkaline dry battery unit is called
BUD-8000(G),BUD-8000(G1).
The battery unit can be changed even by the end users.

Specification for safety
・Ex ia ⅡC T4 Ga (without NC-6215) ・Ex ia ⅡB T4 Ga (with NC-6215)
・・Ⅱ 1 G Ex ia ⅡC T4 Ga (without NC-6215)
Ⅱ 1 G Ex ia ⅡB T4 Ga (with NC-6215)

・Ambient temperature range for use : -20 °C to +50 °C
・Ambient temperature range during battery charging : 0 °C to +40 °C

Electrical data

・Power supply of Li-ion battery unit : BUL-8000(G),BUL-8000(G1)
Two parallel connected Li-ion cells used in battery pack BP-8000,BP-8000(1) are from type Maxell
INR18650PB1. Um = 250 V.
・Power supply of alkaline battery unit : BUD-8000(G),BUD-8000(G1)Powered by three series connected Alkaline AA batteries, type LR6 manufactured by Toshiba.
・Backup battery type CR1220 manufactured by Maxell.

Certificate numbers
・IECEx Certificate number : IECEx KEM 10.0038
・ATEX Certificate number : KEMA 10ATEX 0085

List of standards
・IEC 60079-0: 2017
・IEC 60079-11: 2011

・EN IEC 60079-0:2018
・EN60079-11:2012

WARNING・Do not charge in hazardous location.
・Do not charge it expect by genuine charger.
・Do not replace battery unit in hazardous location.
・Do not replace dry batteries in hazardous location.
・Do not attempt to disassemble or alter the instrument.
・Use only battery unit type BUD-8000(G),BUD-8000(G1) with three series connected Alkaline
AA batteries, type LR6 manufactured by Toshiba, or use chargeable battery unit
type BUL-8000(G),BUL-8000(G1).

INST. No. 0 0 0 0 0 0 0 0 0 0 0
AB C
DE
A: Manufacturing year (0-9)
B: Manufacturing month (1-9,XYZ for Oct.-Dec.)
C: Manufacturing lot
D: Serial number
E: Code of factory

Additional information

The performance of the Portable Gas Monitor GX-8000, as a safety device, is not covered bythis certificate.
2-7-6 Azusawa, Itabashi-ku, Tokyo, 174-8744, JapanPhone: +81-3-3966-1113
Fax: +81-3-3558-9110 GIII
E-mail: intdept@rikenkeiki.co.jp
Web site: https://www.rikenkeiki.co.jp

11

3

Product Components
3-1. Main unit and standard accessories
After opening the package, check the main unit and accessories.
If anything in the following list is not included, contact RIKEN KEIKI.
<Main Unit>
GX-8000
main unit<Standard Accessories> AC powered charger: 1
 Gas sampling probe
and gas sampling hose: 1
 Shoulder strap: 1

Li-ion battery unit

 Operating manual Product warranty

DANGER
About explosion-proof of main unit Do not modify or change the circuit or structure, etc.
 When measuring the oxygen concentration, do not measure anything but a mixture of air andcombustible gases or vapors and toxic gases.
 When using this gas monitor in a hazardous area, take the following countermeasures forpreventing dangers resulting from electrostatic charges.
(1) Wear anti-static clothes and conductive shoes (anti-static work shoes).
(2) For indoor use, use the gas monitor while standing on a conductive work floor (with aleakage resistance of 10 MΩ or less).
 The battery unit that can be connected vary according to Explosion-proof approval No. of mainunit.

Model/Explosion-proof approval No.
of main unit

Model/Explosion-proof approval No.
of battery unit that can be connected

GX-8000 / TC19439

BUL-8000(G) / TC19437
BUD-8000(G) / TC19438

GX-8000 / TC21222

BUL-8000(G1) / TC21223
BUD-8000(G1) / TC21224

12

DANGER The specifications of main units are as follows:
Pump circuit:
Allowable voltage of 4.95 V, allowable current of 1.12 A, andallowable power of 1138 mW
Combustible gas sensor circuit: Allowable voltage of 4.95 V, allowable current of 0.834 A, andallowable power of 853 mW
Buzzer circuit:
Allowable voltage of 4.95 V, allowable current of 0.431 A, andallowable power of 441 mW
Main circuit:
Allowable voltage of 4.95 V, allowable current of 0.717 A, andallowable power of 733 mW
Backup circuit:
3.0 VDC, 10 µA
Ambient temperature:-20 °C to +50 °C
 Explosion-proof grade of main units are Ex ia ⅡC T4 X.
About explosion-proof of battery unit Do not modify or change the circuit or structure, etc.
 When using this gas monitor in a hazardous area, take the following countermeasures forpreventing dangers resulting from electrostatic charges.
(1) Wear anti-static clothes and conductive shoes (anti-static work shoes).
(2) For indoor use, use the gas monitor while standing on a conductive work floor (with aleakage resistance of 10 MΩ or less).
 The main unit that can be connected vary according to Explosion-proof approval No. of battery
unit.

Model/Explosion-proof approval No.
of battery unit

Model/Explosion-proof approval No.
of main unit that can be connected

BUL-8000(G) / TC19437
BUD-8000(G) / TC19438

GX-8000 / TC19439

BUL-8000(G1) / TC21223
BUD-8000(G1) / TC21224

GX-8000 / TC21222

 The specifications of lithium ion battery units are as follows:
Pump circuit:
Maximum voltage of 4.25 V, maximum current of 1.12 A, andmaximum power of 901 mW
Combustible gas sensor circuit: Maximum voltage of 4.25 V, maximum current of 0.768 A, andmaximum power of 618 mW
Buzzer circuit:
Maximum voltage of 4.25 V, maximum current of 0.410 A, andmaximum power of 330 mW
Main circuit:
Maximum voltage of 4.25 V, maximum current of 0.653 A, andmaximum power of 526 mW
Battery charging contact:
Allowable current of 250 VAC 50/60 Hz
Ambient temperature:-20 °C to +50 °C
 Explosion-proof grade of lithium ion battery units are Ex ia ⅡC T4.

 The specifications of dry battery units are as follows:
Pump circuit:

Maximum voltage of 4.95 V, maximum current of 1.12 A, andmaximum power of 1138 mW
Combustible gas sensor circuit: Maximum voltage of 4.95 V, maximum current of 0.834 A, andmaximum power of 853 mW
Buzzer circuit:
Maximum voltage of 4.95 V, maximum current of 0.431 A, andmaximum power of 441 mW
Main circuit:
Maximum voltage of 4.95 V, maximum current of 0.717 A, andmaximum power of 733 mW
Power supply:
4.5 VDC, 250 mA (Type LR6 manufactured by Toshiba, 3 pcs)
Ambient temperature:-20 °C to +50 °C
 Explosion-proof grade of dry battery units are Ex ia ⅡC T4.
13

DANGER
About combination
Make sure that the product model on the nameplate, and combination of main unit and battery unit
is correct.
Inappropriate combinations of models deviate from the range of explosion-proof certification.
 IP protection class: IP20



NOTE

Check the model of the battery unit with the nameplateaffixed to the unit.
A nameplate indicating a compatible model is affixed
to the battery unit to avoid using the gas monitor in
combination with a wrong unit.
Check this information and use a correct combination.
(Top view of battery unit)

Nameplate(Side view of battery unit)14

3-2. Names and functions for each part
<Outline Drawing>

15

(1)
(2)
(3)
(4)

LCD display
Buzzer sound opening
Alarm LED arrays
Infrared communication port(5) ▲/AIR switch(6) ▼/RESET switch(7) DISPLAY switch(8) POWER/ENTER switch(9) Gas inlet(10) Gas outlet(11) Recharging jack cover(12) Recharging indicator lamp(13) Sensor cover(14) Activated carbon filter knob

(15) Battery unit screws

Displays gas concentrations, alarms, etc.
Emits a buzzer sound at an alarm. (Do not block it.)
The lamp blinks in response to an alarm.
Used to carry out data communications with a PC in data logger
mode.
Keep this switch pressed to perform fresh air adjustment.
When an alarm occurs, press this switch to reset the alarm.
Press this switch to change between display modes.
Turns on and off the power.
Connect a sampling hose to this port.
Exhausts the gas drawn into the gas monitor. (Do not block it.)
Remove this cover to connect an AC powered charger and recharge
the batteries.
Lights up in red during recharging and goes off when recharging iscompleted.
There are sensors inside. May be opened only when the sensor is tobe replaced.
Turn this knob to detach and replace the activated carbon filter. No
activated carbon filter is used on a type that does not measure carbon
monoxide. Keep this knob tightened at all times.
Turn these screws to detach and replace the battery unit.

CAUTION Do not jab the buzzer opening with a sharp-pointed item. The unit may malfunction or getdamaged, allowing water or foreign substance, etc. to get inside.
 Do not remove the panel sheet on the display. The water-proof and dust-proof performances will
be deteriorated.
 Do not affix a label on the infrared port. Infrared communications can no longer be conducted.

16

<LCD Display>(1) Pilot indicator(5) Pump driving
indicator(2) Combustible gas
concentration digitaland bar display(6) Oxygen
concentration digitaland bar display(3) Carbon monoxide
concentration digitaland bar display(7) Hydrogen sulfide
concentration digitaland bar display(4) Battery level icon

(8) Clock display

(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)

Pilot indicator
Combustible gas
concentration
digital and bar display
Carbon monoxide
concentration
digital and bar display
Battery level display
Pump driving indicator
Oxygen concentration
digital and bar display
Hydrogen sulfide
concentration
digital and bar display
Clock display

Displays the operating status in the detection mode. Normal: Blinking
Displays the gas concentration as a numeric value and a level in the bar
graph.
Displays the gas concentration as a numeric value and a level in the bar
graph.
Displays the battery level. See the information below for the meanings ofbattery level icons.
Displays the suction status in the detection mode. Normal: Rotating
Displays the gas concentration as a numeric value and a level in the bar
graph.
Displays the gas concentration as a numeric value and a level in the bar
graph.
Displays the current time.

NOTE
The meanings of battery level icons are as follows:: Sufficient /: Low /: Needs recharging
If the battery level is lower than the above, the inside of the battery icon starts to blink (

17

).

4

How to Use
4-1. Before using the gas monitor
Not only the first-time users but also the users who have already used the product must follow the operating
precautions.
Ignoring the precautions may damage the gas monitor, resulting in inaccurate gas detection.

4-2. Preparation for start-up
Before starting gas detection, read and understand the following precautions. Ignoring these precautions
may prevent correct gas detection.
Check that the battery level is sufficient.
Check that there is no bend or hole in the gas sampling hose.
Check that the filter in the gas sampling probe is free of dust or clogging.
Check that the gas monitor, gas sampling probe, and gas sampling hose are connected properly.

<Recharging of Batteries>
When the gas monitor is used for the first time, or when the battery level is low, be sure to use theaccessory AC powered charger to recharge the batteries.






CAUTION

Use the dedicated AC powered charger.
Recharge the batteries in a non-hazardous area.
Recharge the batteries at ambient temperatures between 0 °C to 40 °C.
Do not use the gas monitor while recharging it. Correct measurements cannot be obtained.
Furthermore, the batteries get deteriorated more quickly and may have a shorter life.
 The AC powered charger is not water-proof or dust-proof. Do not recharge the batteries while thegas monitor is wet.
 The AC powered charger is not explosion-proof.

18

(1) Open the recharging jack cover of the gas monitor.

CAUTION
Do not pull the recharging jack cover too hard.
It may get damaged.

(2) Put the plug of the AC powered charger into the recharging jack of
the gas monitor.
(3) Connect the AC powered charger to the wall electric outlet.
When recharging is started, the recharging indicator lamp lights up(red).
(Recharging time: Three hours at the maximum until the batteries are fully recharged)(4) When recharging is completed, the recharging indicator lamp goes off.
(5) When recharging is completed, disconnect the AC powered charger from the wall electric outlet.
(6) Pull out the AC powered charger plug from the power jack of the gas monitor and reattach therecharging jack cover. Put the recharging jack cover as far as it will go.

CAUTION Do not use the gas monitor with the recharging jack cover detached. Dust or water may get into
the gas monitor, causing it to malfunction. Replace the recharging jack cover if it is damaged.
 If the recharging jack cover is not completely closed, water may get in from the power jack. The
same thing occurs if a minute foreign substance is caught beneath the cover.
 Disconnect the AC powered charger from the wall electric outlet while it is not in use.

NOTE

 During recharging, the battery pack may get hot, but this is not abnormal.
 The temperature of the gas monitor is high immediately after recharging is completed. Let it leave for10 minutes or more before using it. Otherwise, correct measurements may not be obtained.
 When fully recharged batteries are recharged again, the recharging indicator lamp does not go on.

19

<Attaching Batteries>(when the optional unit BUD-8000(G) ,BUD-8000(G1) are used)
When the gas monitor is used for the first time, or when the battery level is low, attach new AA alkaline
batteries.

CAUTION<Replacement> Turn off the power of the gas monitor before replacing the batteries.
 Replace the batteries in a non-hazardous area.
 Replace all of the three batteries with new ones at one time.
 Pay attention to the polarities of the batteries.
 If the battery cover fixing screw is not completely tightened, the dry batteries may drop off orwater may get in through the clearance. Water may also get in if a minute foreign substance iscaught beneath the battery unit.
<Batteries> Use AA alkaline batteries.
Rechargeable batteries cannot be used.
(1) Using a flathead screwdriver or coin, turn the battery
cover fixing screw counterclockwise to open thebattery cover.
(2) Paying attention to the polarities of batteries, replace
all the three batteries with new ones.
(3) Close the battery cover and tighten the battery coverfixing screw.

20

<Detaching Battery Unit>(1) Loosen the two battery unit screws.
(They need not be completely detached.)(2) Detach the battery unit.
(3) Attach a new battery unit.

NOTE
Make sure that the battery unit is installed incorrect orientation by checking the locations of theconnection terminal and projection portions.
(4) Securely tighten the two battery unit screws.

CAUTION Turn off the power of the gas monitor before
replacing the battery unit.
 Detach and reattach the battery unit in a
non-hazardous area.
 If the battery unit screw is not completely
tightened, the battery unit may drop off orwater may get in through the clearance.
Water may also get in if a minute foreign
substance is caught beneath the batteryunit.
 Do not damage the rubber seal.
 To maintain the water-proof and dust-proof
performances, it is recommended to replace
the rubber seal every two years, whether or
not it has an abnormality.
Bottom view21<Connection of Gas Sampling Probe and Gas Sampling Hose> Attach the gas sampling probe to the end of the gas sampling hose.
 Connect the sampling hose securely to the gas inlet (GAS IN) of the gas monitor.

Insert the sampling hose to the gas inlet (GAS IN) until it clicks into
place to ensure connection.

CAUTION Use only a gas sampling hose specified by RIKEN KEIKI.
 Use the gas monitor with the gas sampling probe connected so that no foreign substance isdrawn into it.
 Connect a gas sampling probe and a gas sampling hose by fastening them manually without
using any tool. If they are fastened too tightly using a tool, the plastic part of the gas samplingprobe may be broken.

224-3. Basic operating procedures
Normally, the detection mode is used for normal operations. (The detection mode is activated after the
power is turned on.)<<Detection Mode>>
RESET

AIR (long pressing)<<Gas Alarm Status>>(Self-latching <Reset after
Recovery to Normal Status>)<<Air Calibration Mode>>

DISPLAY<<Fault Alarm Status>><<Display and Setting Mode>>(Self-latching)23

4-4. How to start the gas monitor<<Start-up Procedure>>(About 30 seconds)
Keep the POWER switch pressed for three seconds or more.

↓
LCD
Alarm lamp lights up.
Buzzer sounds once. (Beep)

All LCDs light up.

↓
Date/Time Display↓
Battery Voltage Display↓
Gas Name Display↓
Full Scale Display↓
First Alarm Setpoint Display↓
Second Alarm Setpoint Display

24

↓
STEL Alarm Setpoint Display↓
TWA Alarm Setpoint Display↓
ID Display↓
Buzzer sounds twice. (Beep, beep)

Detection Mode

CAUTION
After start-up, perform air calibration before performing gas detection (air calibration mode).

NOTE A sensor abnormality alarm is issued before the detection mode is entered if there is any abnormality
in the sensor. Press the RESET switch. This will reset the sensor abnormality alarm temporarily, set
the gas concentration display that was abnormal on the sensor to ---, and start gas detection. However,notify the abnormality to RIKEN KEIKI promptly. Gas for which there was an abnormality in the sensor
cannot be detected. However, the alarm cannot be reset if there is an abnormality in all the sensors.
 If there is an abnormality in the built-in clock, a fault alarm [FAIL CLOCK] may be issued. Press the
RESET switch. The fault alarm is temporarily reset, and measurement is started with incorrect clock
time.

25

4-5. How to detect
In the detection mode, put the gas sampling probe close to the detection area and take the reading on thedisplay.
Display example<- Display example
CH4 concentration:
O2 concentration:
CO concentration:
H2S concentration:
Time:
Battery level:

0 %LEL
20.9 %
0 ppm
0 ppm
9:30
Sufficient

DANGER While conducting measurement in a manhole or confined space, do not lean over or look into the
manhole or closed space. It may lead to dangers because oxygen-deficient air or other gases
may blow out.
 Oxygen-deficient air or other gases may blow out from the gas exhausting outlet. Never inhale
the air or gases.
 High-concentration (more than LEL) gases may blow out. Never use fire near the gas monitor.

WARNING The gas monitor is designed to draw gases around it under the atmospheric pressure. If
excessive pressure is applied to the gas inlet and outlet (GAS IN, GAS OUT) of the gas monitor,
detected gases may be leaked from its inside, thus leading to dangers. Be sure that excessive
pressure is not applied to the gas monitor while used.
 Do not connect the sampling hose directly to a location with a pressure higher than theatmospheric pressure. The internal piping system may be damaged.
 When the fresh air adjustment is performed in the atmosphere, check the atmosphere forfreshness before beginning the adjustment. If other gases exist, the adjustment cannot be
performed properly, thus leading to dangers when the gas leaks.
 Issuance of a gas alarm indicates that there are extreme dangers. Take proper actions based onyour judgment.
 Before use, check that there remains sufficient battery power. When the gas monitor is used forthe first time or is not used for a long period, the batteries may be exhausted. Either fullyrecharge the batteries or replace them with new ones before use.
 If a low battery alarm occurs, gas detection cannot be conducted. If the alarm occurs during use,turn off the power and promptly recharge the batteries in a non-hazardous area.
 Do not block the buzzer sound opening. No alarm sound can be heard.

26

CAUTION

 Before performing gas detection, attach the gas sampling probe provided with the gas monitor toprevent disturbances by air dust.
 When you measure concentrations of oxygen in inert gases for a long time, the carbon dioxide
concentration in the air must be 15 % or less. When you use the gas monitor in the air with acarbon dioxide concentration of 15 % or higher, perform measurement in as short time as
possible. Using the gas monitor under high concentrations for a long time may shorten the life of
the oxygen sensor.
 An oxygen concentration higher than a certain level is required for the combustible gas %LEL
sensor of the gas monitor to correctly detect gases and display concentrations.
 During combustible gas detection (%LEL range), long-time detection of a high-concentration
combustible gas may adversely influence the sensor.
 Use the gas monitor with the LCD display facing upward. The gas monitor, when used with the
LCD display in a tilted or flat status, may not display correct values.

NOTE If the combustible gas reading exceeds 100 %LEL, the CO reading rises temporarily but this is notabnormal.
 In a low-temperature environment, the operating time is shortened due to the battery performance
property.
 At a low temperature, the response of the LCD display may get slow down.
 If a combustible gas with a higher concentration than %LEL is drawn, some gas may remain in the gas
sampling hose due to adsorption in the hose, gas sampling probe, etc. After drawing ahigh-concentration combustible gas, clean the gas monitor to remove the adsorbed gas (draw fresh air
and check that the reading becomes zero).
Performing fresh air adjustment before cleaning it completely will result in inaccurate adjustment,
giving adverse influence on measurement. In such a case, remove the gas sampling hose before
performing fresh air adjustment to avoid inaccurate adjustment.
 Perform gas detection in the vol% range (Type-A and E only) in a place where the presence of ahigh-concentration combustible gas is known.

NOTE<Influence of Coexisting Gases on High-Concentration Combustible Gas Sensor> (TYPE-A and E Only)
A thermal-conductivity sensor that detects high-concentration combustible gases, based on the principleof detection using a difference in thermal conductivities of gases, may display a reading that is disturbed
by a considerable change in the concentration of gases other than the combustible gases that coexist in
the atmosphere.
However, the influence of oxygen on readings can be automatically corrected by the sensor, which
detects oxygen at the same time, by feeding back a change in the oxygen concentration to the detection
result of high-concentration combustible gases.
If coexisting gases other than oxygen undergo a high concentration change, the influence from thechange cannot be automatically corrected. This sensor is adjusted to be able to detect high-concentration
combustible gases in the air as well as in an nitrogen atmosphere. If the composition of the atmosphereother than nitrogen is known in advance, adjusting the sensor in accordance with the atmosphere canalleviate influences on readings. For information on the adjustment procedure, see the separate'Maintenance Manual.'27

<Manual Memory>
Any instantaneous value during measurement can be recorded.
Up to 256 points of data can be recorded. When the number of recorded data points reaches the maximum,
recorded data will be overwritten, starting from the oldest data.
(1) In the detection mode, keep the ▼/RESET switch pressed and press the ▲/AIR switch to prepare forrecording (about one second). The following screens are displayed in turn on the gas monitor.

NOTE
The screen displays the memory number, date, and instantaneous value in turn. Go to the next step toexecute recording. No value is recorded at this point yet. If you do not want to record a value, press the
DISPLAY switch to return to the detection mode.
(2) Press the ENTER switch. The date and the instantaneous value at the time when the ENTER switch ispressed are recorded.
(3) When [END] is displayed, the recording is completed.

Returns to the detection mode.

28

<Auto Range Switching Point> (TYPE-A and E Only)
If Auto Range is set on a type with the vol% range for combustible gases, the display is automaticallyswitched to the vol% range when the concentration of a detected combustible gas exceeds 100 %LEL.
When the concentration drops, the display returns to the %LEL range again. The following shows anexample of switching timing.
Diagram of gas concentrations and range switching timing under Auto Range setting
CH4concentration

5 vol%(100 %LEL)
3 vol%(60 %LEL)%LEL range

vol% range

Switching point%LEL range

Switching point

CAUTION
An oxygen concentration higher than a certain level is required for the combustible gas %LEL
sensor of the gas monitor to correctly detect gases and display concentrations. For the sake of moreaccurate gas detection and concentration display, therefore, this gas sensor may perform detection
using the vol% sensor if the built-in oxygen sensor of this unit detects an oxygen concentration
lower than a certain level in the atmosphere.
In other words, the display changes at the timing shown above when the oxygen concentration isequal to or higher than a certain level. If it is lower than a certain level, however, the vol% sensor isused for detection even if the combustible gas concentration is lower than the switching point.

29

4-6. Modes
Details on each mode are provided as follows. (* Operations are slightly different depending on the type.)
Mode
Item
LCD display
Details
Detection―
Concentration display
Normal state
Mode

Air Calibration
Mode―[AIR CAL]

Perform the zero adjustment.

Display andSetting Mode

Combustible
Gas
Measurement
Range Setting[HC RANGE]

Used to select a combustible gas
measurement range manually.
(TYPE-A and E only)

Peak Display[PEAK]

Display the maximum concentration (orminimum concentration for oxygen)detected during measurement frompower-on to the present.

STEL Value
Display[STEL]

Display the STEL value after power-on.
(TYPE-A, B, C, and D only)

TWA Value
Display[TWA]

Display the TWA value after power-on.
(TYPE-A, B, C, and D only)

Alarm Setpoint [ALARM-P]
Display
Alarm Test

Display the full scale and alarm setpointvalues and check the alarm operations forthe settings displayed.

Pump
ON/OFF
Setting[PUMP OFF]

Used to turn on/off the pump operations.

ID Setting[ID SELECT]

Display an ID if it has been set in advance.
Also used to change or set an ID.

Log Data
Display[REC.DATA]

Display data recorded to the manual
memory.

30

4-7. Air calibration mode
Press the AIR switch.

Keep pressing the AIR switch.
Changes the display to [Adj
HOLD AIR].

When [RELEASE] isdisplayed, release the AIR
switch.
A 30-second countdown isstarted on the LCD.
(TYPES-A and E only)

When the zero adjustment is
successfully completed, [END]
is displayed, and you return tothe detection mode.

WARNING
When air calibration is performed in the atmosphere, check the atmosphere for freshness before
beginning the calibration. If other gases exist, the adjustment cannot be performed properly, thus
leading to dangers when the gas leaks.

CAUTION Perform air calibration under pressure and temperature/humidity conditions close to those in theoperating environment and in fresh air.
 Perform air calibration after the reading is stabilized.
 If there is a sudden temperature change of 15 C or more between the storage and operation
locations, turn on the power of the gas monitor, let it leave for about 10 minutes in a similar
environment to the operation location, and perform air calibration in fresh air before using it.

31

NOTE

 Air calibration can be performed even when there is a gas alarm.
 If the air calibration fails, it displays [FAIL AIR CAL] and which sensor has
become faulty. Press the RESET swtich to reset the fault alarm (calibration
failure). When the alarm is reset, the value before calibration is displayed.
If CH4 sensor is faulty

32

4-8. Display/setting modeThis mode allows you to change various displays and settings.
Every time the DISPLAY switch is pressed, various screens are displayed in turn.
(* Operations are slightly different depending on the type.)
LCD
Detection Mode

Display and Setting Mode
Combustible Gas Measurement
ENTER Range Setting P35

Combustible Gas Measurement
Range Setting
Used to select a combustible gas
measurement range manually.
(TYPE-A and E only)

PEAK Value Display
Display the maximum
concentration (or minimum
concentration for oxygen)detected during measurementfrom power-on to the present.
STEL
Display the STEL value after
power-on.
(TYPE-A, B, C, and D only)

TWA
Display the TWA value after
power-on.
(TYPE-A, B, C, and D only)

Full Scale Display/Alarm Setpoint
ENTER Display/Alarm Test
 P37

Full Scale Display/Alarm
Setpoint Display/Alarm Test
Display the full scale and alarm
setpoint values and check thealarm operations for the settings
displayed.

33

Pump ON/OFF Setting
Used to turn on/off the pump
operations.

ID Display/Selection
Display an ID if it has beenregistered in advance. Also used
to select an ID.

Log Data Display
Display concentration data
recorded to the manual memory.

ENTER

Pump ON/OFF Setting
 P38

ENTER

ID Display/Selection
 P39

ENTER

Log Data Display
 P40

To Detection Mode

NOTE
The gas monitor automatically returns to the detection mode in about 20 seconds if the gas monitor is left
unoperated.
However, the gas monitor does not automatically return to the detection mode if the pump operation is set
to OFF.

34

<Combustible Gas Measurement Range Setting [HC RANGE]> (TYPE-A and E Only)
The models that can display combustible gas levels in two ways, "%LEL range" and "vol% range,"
automatically switch between these two displays according to the gas concentration or oxygen
concentration, from "%LEL range" to "vol% range" and vice versa. They also support manual selection of
measurement range.
(1) Press the DISPLAY switch and select the combustible gas measurement range setting from thedisplay/setting mode menu.
The following screens are displayed in turn on the gas monitor.

(2) Press the ENTER switch.

NOTE
If you do not want to make a change, press the DISPLAY switch to return to the display/setting modemenu.
(3) Every time the ▲ or ▼ switch is pressed, the measurement range menus, [AUTO RANGE] (automatic
switching), [ONLY VOL] (fixed to the vol% range), and [ONLY LEL] (fixed to the %LEL range), aredisplayed in turn.
Press the ▲ or ▼ switch to select a measurement range and press the ENTER switch.

(4) When [END] is displayed, the setting is completed.

The display/setting mode menu is displayed again.
(5) After completion, press the DISPLAY switch several times until it returns to the detection mode.

35

CAUTION

 No gas alarm is triggered in the combustible gas vol% range-only setting.
In the vol% range-only setting, the screen displays [No ALARM] because no alarm is triggered.
 Be careful because the %LEL range-only setting screen does not appear different from the auto
range setting screen.
Even if the concentration exceeds the full scale, the screen does not automatically switch to the
vol% range.
[No ALARM] display

vol% range only

NOTE
During vol% range-only measurement, [vol%] and [No ALARM] displays blink.

36%LEL range only<Full Scale Display/Alarm Setpoint Display/Alarm Test [ALARM-P]>
Display the full scale or alarm setpoint values and check the alarm operations for the settings displayed.
(1) Press the DISPLAY switch and select the "full scale display/alarm setpoint display/alarm test" from thedisplay/setting mode menu. The following screens are displayed in turn on the gas monitor.

(2) Press the ENTER switch to enter the alarm setpoint or other display.

NOTE
If you do not want to enter any display, press the DISPLAY switch to return to the display/setting modemenu.
(3) Every time the ▲ or ▼ switch is pressed, the full scale and alarm setpoint menus, i.e., full scale display,first alarm setpoint display, second alarm setpoint display, STEL alarm setpoint display, and TWA
alarm setpoint display, are displayed in turn.
Press either the ▲ or ▼ switch to select a setting that you want to check.
Select one of the following screens:

Full Scale Display

First Alarm Setpoint Display([WARNING])

Second Alarm Setpoint Display([ALARM])

STEL Alarm Setpoint Display (*)

TWA Alarm Setpoint Display(*)* TYPE-A, B, C, and D only

(4) Press the ENTER switch to perform alarm test. The alarm operation on this screen can be checked.
Press any switch to stop the alarm operation.
(5) Press the DISPLAY switch to exit the alarm setpoint display or alarm test. The display/setting modemenu is displayed again.
(6) After completion, press the DISPLAY switch several times until it returns to the detection mode.

37

<Pump ON/OFF Setting [PUMP OFF]>
Used to turn on/off the pump operations.

CAUTION While the pump operation is set to OFF, no gas detection is performed because no gas is drawn.
 The gas monitor does not automatically return to the detection mode if the pump operation is set
to OFF.
(1) Press the DISPLAY switch and select the pump ON/OFF setting from the display/setting mode menu.
The following screens are displayed in turn on the gas monitor.

(2) Press the ENTER switch to set the pump operation to ON or OFF.

NOTE
If you do not want to set the pump operation or ON or OFF, press the DISPLAY switch to return to thedisplay/setting mode menu.
(3) Every time the ENTER switch is pressed, the pump operation is turned ON or OFF.

Pump ON

Pump OFF

NOTE
While the pump operation is set to OFF, only the ENTER switch is enabled.
(4) To return to the detection mode, press the ENTER switch to set the pump operation to ON.
(5) After completion, press the DISPLAY switch several times until it returns to the detection mode.

38

<ID Display/Selection [ID SELECT]>
Display an ID if it has been registered in advance. Also used to select an ID.
(1) Press the DISPLAY switch and select the ID display/selection from the display/setting mode menu.
The following screens are displayed in turn on the gas monitor.

(2) Press the ENTER switch to set or select an ID.

NOTE

 If you do not want to set or select an ID, press the DISPLAY switch to return to the display/setting
mode menu.
 On this gas monitor, either of the IDs from ST-ID000 to ST-ID255 has been registered, unlessotherwise specified.
 The data logger management program (option) is required to register or change an ID. Please contact
RIKEN KEIKI.
(3) Press either the ▲ or ▼ switch to select an ID.
Every time the ▲ or ▼ switch is pressed, the ID number increases or decreases (000 - 255).

(4) Press the ENTER switch.
(5) When [END] is displayed, the setting is completed.

The display/setting mode menu is displayed again.
(5) After completion, press the DISPLAY switch several times until it returns to the detection mode.

39

<Log Data Display [REC.DATA]>
Display concentration data recorded to the manual memory.
(1) Press the DISPLAY switch and select the log data display from the display/setting mode menu.
The following screens are displayed in turn on the gas monitor.

(2) Press the ENTER switch to display the log data.

NOTE
If you do not want to display the log data, press the DISPLAY switch to return to the display/setting modemenu.
(3) Every time the ▲ or ▼ switch is pressed, the log data menus are displayed in turn.
Press either the ▲ or ▼ switch to select log data that you want to check. The log data menu displays
the year, month, day, time, and memory number.

(4) Press the ENTER switch to display the selected log data.

(5) If you want to display other log data, press the ENTER switch to return to the log data menu. Repeat
the steps (3) - (5).
(6) After completion, press the DISPLAY switch to return to the detection mode.

4-9. How to exit
Make the gas monitor draw in fresh air. After the display returns to zero (or 20.9 % for oxygen), keep the
POWER/ENTER switch pressed until the power is turned off.

NOTE
If the display is not zero (or 20.9 % for oxygen) when the power is turned off, apurge operation may be performed for 30 seconds at the maximum to clean theinside of the gas monitor.

40

5Operations and Functions
5-1. Gas alarm activation
Gas alarm:

Triggered when the concentration of detected gas reaches or exceeds the alarm setpointvalue. <<Self-latching>>
Alarm display: Notified by blinking of a gas concentration value display, sounding of the buzzer, and lightingof the lamp.
Alarm types: First alarm (WARNING), second alarm (ALARM), OVER alarm, TWA alarm, and STEL alarm<List of Gas Alarms>
Alarm type
OxygenCombustible
gas
HydrogensulfideCarbonmonoxide
BuzzerAlarm lamp

LCD display

First alarm
18.0 % (Japan
specification)
19.5 % (Export
specification)
10 %LEL

Second alarm
25.0 % (Japan
specification)
23.5 % (Export
specification)
50 %LELOVER alarm
40.0 %TWA alarm

STEL alarm

100 %LEL

5.0 ppm

30.0 ppm

100.0 ppm

10.0 ppm

15.0 ppm

25 ppm50 ppm

500 ppm

25 ppm200 ppm

Repeatedlysounds strong
and weakbeeps at about
one second
intervals:
Beep, beep
Repeatedly
blinks at about
one second
intervals.
Gas
concentration
and[WARNING]
display blink.

Repeatedlysounds strong
and weakbeeps at about
0.5 second
intervals:
Blip, blip
Repeatedly
blinks at about
0.5 second
intervals.
Gas
concentration
and[ALARM]
display blink.

Repeatedlysounds strong
and weak beeps
at about 0.5
second intervals:
Blip, blip

Repeatedlysounds strong
and weak beeps
at about one
secondintervals:
Beep, beep
Repeatedly blinks Repeatedly
at about 0.5
blinks at about
second intervals. one second
intervals.
Gas
Gas
concentration and concentration[OVER] display
andblink.
[TWA] display
blink.

41

Repeatedlysounds strong
and weak beeps
at about one
secondintervals:
Beep, beep
Repeatedly
blinks at about
one second
intervals.
Gas
concentration
and[STEL] display
blink.

<Display Operation>
Gas Concentration Display
In a gas alarm, the gas concentration display and the alarm typedisplay blink.
In case of over the detection range (Over Scale), [∩∩∩] is displayedon the LCD.

Display example
Alarm Lamp
The alarm consists of two steps. Each of them is triggered when the respective alarm setpoint value isreached to or exceeded.
Buzzer
The alarm consists of two steps. Each of them sounds when the respective alarm setpoint value isreached to or exceeded.
"Alarm Pattern (H-HH)"

1 second interval
0.5 second interval

RESET

RESET

Concentration

Second alarm
setpoint
First alarm
setpoint

Concentration"Alarm Pattern (L-H)"(* oxygen deficiency alarm)Time

1 second interval
0.5 second interval
RESET
Second alarm
setpoint
First alarm
setpoint

Time

Alarm lamp
BuzzerAlarm lamp
BuzzerWARNING
Issuance of a gas alarm indicates that there are extreme dangers. Take proper actions based onyour judgment.

42

5-2. Fault alarm activation
Fault alarm:
Triggered when an abnormality is detected in the gas monitor. <<Self-latching>>
Alarm display: Notified by display of error messages, sounding of the buzzer, and lighting of the lamp.
Alarm types: Low flow rate, sensor abnormality, battery voltage low, system abnormality, and calibration
failureDetermine the causes and take appropriate actions.
If the gas monitor has problems and is repeatedly malfunctioning, contact RIKEN KEIKI immediately.

<Display Operation>
LCD display

Displays an error message.

Alarm lamp

Repeatedly blinks at about one second intervals.

BuzzerRepeatedly sounds intermittent beeps at about
one second intervals : Blip, beep, blip, beep
Display example

CAUTION To reset a low flow rate alarm ([FAIL LOW FLOW]), remove the cause of the low flow rate, andthen press the RESET switch.
 When the low flow alarm has occurred, the instrument will stop the operation of pump forprotection of inside.
In that case, once, turn off the power to the instrument.
After surely treating the cause of the low flow alarm, press the RESET switch.
After the instrument sucked water, do not press the RESET switch without the treatment forwater.
Even if the low flow alarm is released without the treatment for water etc., the pump will
temporarily start working again.
In this way, the sucked water enters inside the instrument, it may cause a malfunction.

NOTE For information on malfunctions (error messages), see '8. Troubleshooting'.

5-3. Other functions<Calibration History/Various Trend/Event History Functions>
The gas monitor has history and trend functions. To use these functions, contact RIKEN KEIKI.

NOTE
The data logger management program (option) is required to use the history and trend functions. Pleasecontact RIKEN KEIKI.

43

6

MaintenanceThis is an important instrument for the purpose of safety.
To maintain the performance of the gas monitor and improve the reliability of safety, perform a regular
maintenance.

6-1. Maintenance intervals and items
 Daily maintenance: Perform maintenance before beginning to work.
 Monthly maintenance: Perform alarm test once a month.
 Regular maintenance: Please do it more frequently once a year (recommended: more than once every
six months).
Maintenance item
Battery Level
Check
Concentration
Display Check

Flow Rate Check
Filter Check
Alarm Test
Span Adjustment
Gas Alarm Check

Maintenance content
Check that the battery level is sufficient.
Make the gas monitor draw in fresh air and check thatthe concentration display value is zero (or 20.9 vol%on the oxygen deficiency meter). When the reading isincorrect, perform the zero adjustment (fresh air
adjustment) after ensuring that no other gases exist
around it.
See the flow rate indicator to check for abnormalities.
Check the dust filter for dust or clogging.
Check the alarm lamp and buzzer for normal
operation using the alarm test function.
Perform the span adjustment by using the calibration
gas.
Check the gas alarm by using the calibration gas.

44

Daily
maintenance

Monthly
maintenanceRegularmaintenance




























<About Maintenance Services> We provide services on regular maintenance including span adjustment, other adjustments andmaintenance.
To make the calibration gas, dedicated tools, such as a gas cylinder of the specified concentration andgas sampling bag must be used.
Our qualified service engineers have expertise and knowledge on the dedicated tools used for services,along with other products. To maintain the safety operation of the gas monitor, please use ourmaintenance service.
 The followings are typical maintenance services. For more information, please contact RIKEN KEIKI.
Main Services
Battery Level
Check
Concentration
Display Check
Flow Rate Check
Filter Check
Alarm Test
Span Adjustment
Gas Alarm Check: Checks the battery level.
: Verifies that the concentration display value is zero (or 20.9 vol% on the oxygen deficiency
meter) by using the zero gas.
Performs the zero adjustment (fresh air adjustment) if the reading is incorrect.
: Checks the flow rate indicator to find abnormalities.
Checks the flow rate by using an external flow meter to verify the correctness of the flow rate
indicator on the gas monitor. If the flow rate is incorrect, performs the flow rate adjustment.
: Checks the dust filter for dust or clogging.
Replaces a dirty or clogged dust filter.
: Checks the alarm lamp and buzzer for normal operation using the alarm test function.
: Performs the span adjustment by using the calibration gas.
: Checks the gas alarm by using the calibration gas.
 Checks the alarm. (Checks the alarm activation when the alarm setpoint is reached.) Checks the delay time. (Checks time to delay until the alarm is triggered.) Checks the buzzer, lamp, and concentration display. (Check each activation of ALM1 and
ALM2.): Checks dust or damage on surface of the gas monitor, clean and repair such parts of the gas
monitor.
Replaces parts which are cracked or damaged.

Cleaning andRepair of Gas
Monitor(visual diagnosis)
Gas Monitor: Uses the keys to check the operation of functions and parameters.
Operation Check
Replacement of: Replaces consumable parts, such as a sensor, filter and pump.
Consumable Parts

6-2. Gas calibration method
The span adjustment requires dedicated equipment and a calibration gas. Request RIKEN KEIKI for it.
If you perform the span adjustment for yourself, prepare these tools in advance and perform the adjustment
in accordance with the 'Maintenance Manual.'

CAUTION
Do not use a lighter gas to check the sensitivity of the gas monitor. A constituent of the lighter gas
may deteriorate the sensor performances.

45

6-3. How to clean
Clean the gas monitor if it becomes extremely dirty. The gas monitor must be turned off while cleaning it.
Use a waste cloth to remove dust. Do not use water or organic solvent for cleaning because they may cause
malfunctions.
Because an extremely large amount of dust inside the gas sampling hose may disturb the gas detection, it
must be cleaned with dry AIR, etc.

CAUTION
When cleaning the gas monitor, do not splash water over it or use organic solvents such as alcoholand benzene on it. The surface of the gas monitor may be discolored or damaged.

NOTE
When the gas monitor gets wet, water may remain in the buzzer sound opening or clearances. Drain
water as follows:(1) Wipe away moisture on the gas monitor thoroughly using a dry towel, cloth, etc.
(2) While holding the gas monitor firmly, shake it about ten times with the buzzer sound opening facing
downward.
(3) Wipe away moisture coming out from the inside thoroughly using a towel, cloth, etc.
(4) Place the gas monitor on a dry towel, cloth, etc. and let it stand at normal temperatures.

6-4. Parts replacement<Replacement of Consumables>
Sensor Replacement
The built-in sensors of the gas monitor have a validity period and must be replaced regularly.
The sensor life has expired if, for example, the sensors cannot be calibrated in span adjustment, thereadings do not come back after fresh air adjustment, or the readings fluctuate. Contact RIKEN KEIKI. The
warranty period is one year for all the sensors.
Dust Filter Replacement Procedure
Because the dust filter may gradually get dirty or clogged over the time, it must be replaced regarding theoperating conditions. Check the dust filter, and then replace it as necessary.
The gas monitor has various built-in filters.
Gas sampling probe
Because the dust filter may gradually get dirty or clogged over time, it must be replaced regularly according
to the operating conditions.
It must be replaced especially when it shows a sign of water absorption, low flow rate or contamination①

Rotate the end of the probe
counterclockwise and remove it.
A round dust filter is contained here.
Check it for contamination or clogging.
Replace the dust filter if it is contaminatedheavily or clogged.

②③

Take out the filter and replace it with newone.
Reattach the filter case.

NOTE Use only the filters specified by RIKEN KEIKI.

46

How to replace the activated carbon filter

CAUTION Turn off the power of the gas monitor before replacing the activated carbon filter.
 Do not remove the activated carbon filter knob unless the activated carbon filter is to be
replaced. If the activated carbon filter knob is loose (not sufficiently tightened), accurate
measurement may not be possible due to leaks, or water may get inside.
 No activated carbon filter is used on a type that does not measure carbon monoxide. Keep thisknob tightened at all times.
 Use only an activated carbon filter dedicated to the gas monitor (GX-8000). Using a similar
product may have harmful effects on the gas detection performance.

(1) Using a coin, etc., turn the activated carbon filter knob
counterclockwise (in a direction indicated as OPEN in this figure) toremove it.

(2) Pull out to remove the filter case from the activated carbon knob.

(3) Replace the two activated carbon filters in the filter case with new ones.

(4) Attach the filter case to the activated carbon filter knob and put it as far as
it will go.

(5) Attach the activated carbon filter knob to the main unit in an opposite
procedure to Step (1). Tighten it firmly using a coin, etc.

CAUTION
If the knob is not completely tightened, accurate gas measurement may not be possible due toleaks, or water may get inside. The same thing occurs if a minute foreign substance is caught
beneath the knob.

47

<Replacement of Regular Replacement Parts>
List of recommended regular replacement parts
No.
1
2
3
4

Item
Rubber seal
Tube
Pump unit (RP-11)
Li-ion battery pack(BP-8000,BP-8000(1))

Maintenanceintervals
6 months
6 months

Replacement
intervals
2 years
3 - 8 years
1 - 2 years

Quantity(pieces per unit)
1 set
1 set
1
1

Remarks

About 500
cycles ofcharging anddischarging

NOTE
The above replacement intervals are recommendation only. The intervals may change depending on theoperating conditions. These intervals do not mean the warranty periods either. The result of the regular
maintenance may determine when to replace the parts.
The operation of most of the periodical replacement parts must be checked after replacement by a qualified
service engineer.
For the stable operation of the gas monitor and safety, ask a qualified service engineer to take care of
replacement of the parts whose operation must be checked. Please contact RIKEN KEIKI.

48

7

Storage and Disposal
7-1. Procedures to store the gas monitor or leave it fora long time
The gas monitor must be stored under the following environmental conditions.
 In a dark place under the normal temperature and humidity away from direct sunlight In a place where gases, solvents or vapors are not present
Store the gas monitor in a shipping carton, if any, in which the product was delivered.
Store the gas monitor away from dust, etc. if the shipping carton is not available.

CAUTION
If the gas monitor is not used for a long time, turn on the power at least once every six months andcheck that the pump draws in air (about three minutes). The gas monitor, when not activated for along time, may cease to work because of hardening of the grease in the pump motor.

NOTE If the gas monitor with a Li-ion battery unit is not used for a long time, it is recommended to store it
after discharging the batteries until the battery level icon shows one battery mark or so. If the gas
monitor is stored with the batteries fully recharged, the batteries get deteriorated more quickly and may
have shorter life.
 If the gas monitor with a dry battery unit is not used for a long time, store it after removing the batteries.
Battery leaks may result in fire or injury. If the gas monitor is not used for a short time, store it without
removing the batteries. While the power of the gas monitor is OFF, the sensor is energized at all times.
Therefore, it is necessary to store the gas monitor with the batteries in it.

7-2. Procedures to use the gas monitor again
CAUTION
When you use a stopped/stored gas monitor again, do not forget to perform a gas calibration. For
information on readjustment including gas calibration, please contact RIKEN KEIKI.

49

7-3. Disposal of products When the gas detector is disposed of, it must be treated properly as an industrial waste in accordancewith the local regulations.

WARNING Do not disassemble the electrochemical type sensor or galvanic cell type sensor because they
contain electrolyte. Electrolyte may cause severe skin burns if it contacts skin, while it may cause
blindness if it contacts eyes.
If electrolyte is adhered on you clothes, that part on your clothes is discolored or its material isdecomposed. If contact occurs, rinse the area immediately with a large quantity of water.
 Dispose of the batteries in accordance with procedure specified by the local authority.
 When disposing of the gas detector in EU member states, sort the batteries as specified. Handle theremoved batteries according to the classified refuse collection system and recycling system based on
the regulations of EU member states.
Contact RIKEN KEIKI for disposal.
Removing batteries
See '4-2. Preparation for start-up' and take out the batteries.
For BUL-8000(G), BUL-8000(G1)Model
BUL-8000(G)BUL-8000(G1)Type
Lithium ion battery

NOTE




BUL-8000(G), BUL-8000(G1) contains batteries.
Crossed-out recycle dustbin markThis symbol mark is indicated on the products which contain the batteries which fall under EU Battery
Directive 2006/66/EC. Such batteries need to be disposed of as specified by the latest Directive.
This symbol mark indicates that the batteries need to be separated from the ordinary waste and disposed ofappropriately.

50

8Troubleshooting
The troubleshooting does not explain the causes of all the malfunctions which occur on the gas monitor.
This simply helps to find the causes of malfunctions which frequently occur. If the gas monitor shows asymptom which is not explained in this manual, or still has malfunctions even though remedial actions aretaken, please contact RIKEN KEIKI.

<Abnormalities on Unit>
Symptoms
The power cannot
be turned on.

CausesThe battery level is too
low.

Actions
Li-ion battery unit: Recharge the batteries in a
non-hazardous area.
Dry battery unit: Replace all the three dry batteries withnew ones in a non-hazardous area.

The power switch was
For power-on, keep the POWER switch pressed until a
not pressed long enough. beep is heard (about two seconds).
Improper installation ofbattery unit

Check whether battery unit is properly attached to themain unit.

Abnormaloperations

Disturbances by sudden
surge noise, etc.

Turn off and restart the gas monitor.

Key operations are
disabled.

Disturbances by sudden
surge noise, etc.

Systemabnormalities[FAIL SYSTEM]
Systemabnormalities[FAIL SYSTEM]
Error No.000

A circuit abnormality
occurred.

In a non-hazardous area, remove the battery unit once,and reinstall the battery unit, and turn on the power toperform operations.
Request RIKEN KEIKI for repair.

Abnormalities of internal
ROM
Abnormalities of internal
Error No.010
RAM
Abnormalities of internal
Error No.021
FRAM
Abnormalities of internal
Error No.031
FLASH
SensorA sensor has failed.
abnormalities[FAIL SENSOR]
A low battery
voltage alarm isdisplayed.
[FAIL BATTERY]

The battery level is low.

Request RIKEN KEIKI for repair.

Request RIKEN KEIKI to replace the sensor.
(Only at power-on, press the RESET switch to continue
the operation using only the normal sensors to detect
other gases.)
Li-ion battery unit: Turn off the power and recharge it in a
non-hazardous area.
Dry battery unit: Turn off the power and replace the drybatteries with new ones in a non-hazardous area.
51

Symptoms
A low flow rate
alarm is displayed.
[FAIL LOW FLOW]

CausesWater or oil, etc. wasdrawn in.

Actions
Check the gas sampling hose for any damage or mark ofdrawn water or oil, etc.

The gas sampling hose
is clogged.

Check the gas sampling hose for connections, clogging,twisting, etc.

The pump hasdeteriorated.

Request RIKEN KEIKI to replace the pump.

Fresh airadjustment cannot
be performed.
[FAIL AIR CAL]
Clock
abnormalities[FAIL CLOCK]

Fresh air is not suppliedaround the gas monitor.

Supply fresh air.

Abnormalities of theinternal clock

The batteries
cannot berecharged.
(Li-ion battery unit
only)

The charger is notconnected properly.

Make a setting of Date/Time.
If such a symptom is observed repeatedly, the built-in
clock is seemingly malfunctioning. Thus, it must be
replaced. Please contact RIKEN KEIKI.
Connect the AC powered charger to the wall electric
outlet and jack properly.

A recharging circuit
abnormality occurred.
The batteries have been
fully charged.

Request RIKEN KEIKI for repair.
When fully recharged batteries are recharged again, therecharging indicator lamp does not go on.

<Abnormalities of Readings>
Symptoms
The reading rises(drops) and it
remains so.

CausesDrifting of sensor output
Presence of interferencegas

Slow leakEnvironmental changes

A gas alarm istriggered despiteof no gas leak andno otherabnormalities atthe detection
point.
Slow response

Span adjustment
impossible

Presence of interferencegas

Disturbance by noise

Clogged dust filter
Bended or clogged
suction tube or exhausttube
Condensation is formed
inside the suction tube.
Deteriorated sensor
sensitivity
Improper calibration gas
concentration
Deteriorated sensor
sensitivity

Actions
Perform the zero adjustment (fresh air adjustment).
Disturbances by interference gases, such as solvents,
cannot be eliminated completely. For information on
actions, such as removal filter, please contact RIKEN
KEIKI.
A very small amount of the gas to be detected may beleaking (slow leak). Because ignoring it may cause
dangers, take a remedial measure, i.e., taking actions
the same as those for the gas alarm.
Perform the zero adjustment (fresh air adjustment).
In particular, the galvanic cell type is affected by the airpressure.
Disturbances by interference gases, such as solvents,
cannot be eliminated completely. For information on
actions, such as removal filter, please contact RIKEN
KEIKI.
Turn off and restart the gas monitor.
If such a symptom is observed frequently, takeappropriate measures to eliminate the noise.
Replace the dust filter.
Fix the defective parts.

Fix the defective parts.
Replace the sensor unit with a new one.
Use the proper calibration gas.
Replace the sensor unit with a new one.

52

9

Product Specifications
9-1. List of specifications<Japan Ex specification>
Model
Detection principle
Detectable gas

Less than ±1 vol%ＧＸ－８０００
New ceramic catalytic(NC)/Electrochemical (ES)
Thermal conductivity(TE)Combustible gas
Hydrogen sulfide(HC/CH4/H2/C2H2) *1(H2S)
0 - 100 %LEL
0 - 30 ppm/Up to 100 vol%<Up to 100 ppm>
1%LEL/1 vol%0.5 ppm
5 ppm (1st)
10 %LEL (1st)
30 ppm (2nd)
50 %LEL (2nd)
10 ppm (TWA)
100 %LEL (OVER)
15 ppm (STEL)
100 ppm (OVER)
Less than ±5 %LEL (NC)/ Less than ±1.5 ppm
Less than ±5 vol% (TE)Less than 30 sec (T90)
Less than 30 sec(T90)
Less than ±25 %Less than ±3 ppm

Less than 5 sec

Less than 30 sec

Galvanic cell (OS)Measuring range<Service range>
Resolution
Alarm preset point

Oxygen(O2)
0 - 25 vol%<Up to 40 vol%>0.1 vol%
18 vol%(L)25 vol%(H)40 vol%(OVER)

Indicate accuracyLess than ±0.7 vol%(under an identical condition)

Response timeLess than 20 sec (T90)(under an identical condition)

Alarm accuracy

Electrochemical (ES)
Carbon monoxide(CO)0 - 150 ppm<Up to 500 ppm>
1 ppm
25 ppm (1st)
50 ppm (2nd)
25 ppm (TWA)
200 ppm (STEL)
500 ppm (OVER)
Less than ±15 ppm
Less than 30 sec (T90)
Less than ±30 %(under an identical condition)

Alarm-delay timeLess than 15 sec

Less than 30 sec(under an identical condition)

Gas concentration display
Detection method
Suction flow
Various indications
Alarm soundGas alarm indication
Gas alarm action
Trouble alarm・self diagnosis
Trouble alarm indication
Trouble alarm action
Specification of transmission
Various functions
Power supply

LCD (digital)
Pump suction method
Above 0.75 L/min (open flow)
Clock/Battery condition/Pilot indicator/Flow indicator
Above 95 dB (A)(30 cm)
Lamp blinking/Intermittent buzzer/Gas concentration display blinking
Latched
System failure/Sensor failure/Low battery/Calibration failure/Flow failure
Lamp lighting/Intermittent buzzer/Content display
LatchedIrDA
LCD backlight/Data logger/Peak hold/Logged data display/Pump stop
Lithium ion battery unit 【BUL-8000(G), BUL-8000(G1)*2】(Dedicated dry battery unit<three AA batteries>【BUD-8000(G), BUD-8000(G1)*3】 is available.)
Continuous operation time
BUL-8000(G), BUL-8000(G1): Approx. 12 hours (25 °C・Non alarm operation・After full charge)
BUD-8000(G), BUD-8000(G1): Approx. 6 hours (25 °C・Non alarm operation)
Operating temperature-20 °C to +50 °C
Operating humidity
Less than 95 %RH (non-condensing)Operating pressure
Atmospheric pressure (80 kPa to 110 kPa)
Structure
Dust and Water-proof Structure (IP67)
Explosion-proof structure
Intrinsically safe structure
Ex ia ⅡC T4 X
Explosion-proof grade
Outer dimension
Approx. 154 (W)  81 (H)  127 (D) mm (projection excluding)
WeightApprox. 1.1 kg (BUL-8000(G), BUL-8000(G1) when in use)
Approx. 1.0 kg (BUD-8000(G), BUD-8000(G1) when in use)
*1 For JG (Japanese Government) type approval, the factory default setting is either CH4 or HC (specified in the order).
*2 JG (Japanese Government) type approval is only available for the rechargeable battery type (BUL).
*3 In order to meet requirement about explosion-proof, use dedicated dry cell battery when using dry battery unit.

53

<ATEX/IECEx specification>
Model
Detection principle
Detectable gas

Galvanic cell (OS)Measuring range<Service range>
Resolution
Alarm preset point

Oxygen(O2)
0 - 25 vol%<Up to 40 vol%>0.1 vol%
19.5 vol% (L)23.5 vol% (H)
40 vol% (OVER)

Indicate accuracyLess than ±0.7 vol%(under an identical condition)

Response timeLess than 20 sec (T90)

ＧＸ－８０００
New ceramic catalytic(NC)/Electrochemical (ES)
Thermal conductivity(TE)Combustible gas
Hydrogen sulfide(HC/CH4/H2/C2H2)(H2S)
0 - 100 %LEL
0 - 30 ppm/Up to 100 vol%<Up to 100 ppm>
1 %LEL/1 vol%0.5 ppm
5 ppm (1st)
10 %LEL (1st)
30 ppm (2nd)
50 %LEL (2nd)
10 ppm (TWA)
100 %LEL (OVER)
15 ppm (STEL)
100 ppm (OVER)
Less than ±5 %LEL (NC)/ Less than ±1.5 ppm
Less than ±5 vol% (TE)Less than 30 sec (T90)
Less than 30 sec (T90)Electrochemical (ES)
Carbon monoxide(CO)0 - 150 ppm<Up to 500 ppm>
1 ppm
25 ppm (1st)
50 ppm (2nd)
25 ppm (TWA)
200 ppm (STEL)
500 ppm (OVER)
Less than ±15 ppm
Less than 30 sec (T90)(under an identical condition)

Gas concentration display
Detection method
Suction flow
Various indications
Alarm soundGas alarm indication
Gas alarm action
Trouble alarm・self diagnosis
Trouble alarm indication
Trouble alarm action
Specification of transmission
Various functions
Power supply
Continuous operation time
Operating temperature
Operating humidity
Operating pressure
Structure
Explosion-proof structure
Explosion-proof grade

Outer dimension
WeightLCD (digital)
Pump suction method
Above 0.75 L/min(open flow)
Clock/Battery condition/Pilot indicator/Flow indicator
Above 95 dB (A)(30 cm)
Lamp blinking/Intermittent buzzer/Gas concentration display blinking
Latched
System failure/Sensor failure/Low battery/Calibration failure/Flow failure
Lamp lighting/Intermittent buzzer/Content display
LatchedIrDA
LCD backlight/Data logger/Peak hold/Logged data display/Pump stop
Lithium ion battery unit 【BUL-8000(G), BUL-8000(G1)】(Dedicated dry battery unit<three AA batteries>【BUD-8000(G), BUD-8000(G1)】 is available.)
BUL-8000(G) BUL-8000(G1): Approx. 12 hours (25 °C・Non alarm operation・After full charge)
BUD-8000(G) BUD-8000(G1): Approx. 6 hours (25 °C・Non alarm operation)-20 °C to +50 °C
Less than 95 %RH (non-condensing)
Atmospheric pressure (80 kPa to 110 kPa)
Dust and Water-proof Structure (IP67)
Intrinsically safe structure
ATEX
Ⅱ 1 G Ex ia ⅡC T4 Ga (without NC-6215) / Ⅱ 1 G Ex ia ⅡB T4 Ga (with NC-6215)
IECEx
Ex ia ⅡC T4 Ga (without NC-6215) / Ex ia ⅡB T4 Ga (with NC-6215)
Approx. 154 (W)  81 (H)  127 (D) mm (projection excluding)Approx. 1.1 kg (BUL-8000(G), BUL-8000(G1) when in use)
Approx. 1.0 kg (BUD-8000(G), BUD-8000(G1) when in use)

<Combinations of Detected Gases by Type>
TypeA

Oxygen (O2)

Combustible (HC and CH4) *Hydrogen sulfide (H2S)

Carbon monoxide (CO)TypeB

Oxygen (O2)

Combustible (HC and CH4)

Hydrogen sulfide (H2S)

Carbon monoxide (CO)TypeC

Oxygen (O2)

Combustible (HC, CH4 and C2H2)

Hydrogen sulfide (H2S)

TypeD

Oxygen (O2)

Combustible (HC and CH4)

TypeE

Oxygen (O2)

Combustible (HC, CH4 and H2) *TypeF

Oxygen (O2)

Combustible (HC, CH4, and C2H2)

Carbon monoxide (CO)TypeG
Oxygen (O2)
Combustible (H2)
* Range: 0 - 100 %LEL (NC)/- 100 vol% (TE) specifications. Only 0 - 100 %LEL (NC) for other combustible gases.

54

9-2. List of accessories
Standard
accessories







Li-ion battery unit (BUL-8000 (G), BUL-8000 (G1))
AC powered charger
Shoulder strap
Gas sampling hose (1 m spiral)
Gas sampling probe

Optional
accessories




















Dry battery unit (BUD-8000 (G), BUD-8000 (G1))
AA alkaline battery  3
Waist strap
Waist strap fixing tool
Carrying case (leather)
Aluminum trunk case
Shipboard storage box (metal)
Sampling probe holder
Gas sampling hose (with float probe, 8m)
Gas sampling hose 30 m with plummet
Filter tube (CF-8385)
Filter tube fixing belt
Water trap
Relay tube
Set of gas bags (LEL/VOL)
Span cans (CALGAS 4 component mixed gas)
Demand flow valve
Data logger management program

CAUTION
In case of using gas sampling hose 30m with plummet (option), use CF-8385 type filter always.
（※CF-8385 type filter is to waterproof and dust removal applications. Relay tube and the filter fixing
belt will be required together too.)
In case of sucking water without CF-8385 type filter, the water enters to inside instrument, it may
cause a malfunction.

55

10

Definition of Terms
vol%
ppm
%LEL

TWA

STEL

Gas concentration indicated in the unit of one-hundredth of the volume
Gas concentration indicated in the unit of one-millionth of the volume
An abbreviation for "Lower Explosion Limit."
LEL refers to the lowest concentration of a combustible gas in air capable ofcausing explosion when ignited.
An abbreviation for "Threshold Limit Value Time Weighted Average Limit." TWA
refers to a concentration limit of toxic substances as a time weighted average towhich repetitious exposure of almost all the workers in 8-hour work shift or a
40-hour work week does not have harmful effects on their health.
An abbreviation for "Threshold Limit Value Short Term Exposure Limit." STEL
refers to a concentration limit of toxic substances to which everyday exposure ofworkers for 15 continuous minutes lower than TWA does not have harmful
effects on their health.

56