RKI Instruments SC-04 User manual

www.rkiinstruments.com
SC-04
Operator’s Manual
Part Number: 71-0548
Revision: P6
Released: 12/23/21

2 • SC-04
WARNING
Read and understand this instruction manual before operating instrument. Improper use of the
gas monitor could result in bodily harm or death.
Maintenance of the gas monitor is essential for proper operation and correct readings.
Bump test the instrument before each day’s use with a known concentration of the target gas.
A bump test can be done in User Mode’s BUMP item or by applying gas in Measuring Mode.
The instrument does not need to be calibrated unless it does not pass the User Mode bump test
or does not respond appropriately, as defined by the user, in Measuring Mode. For more
information about bump test and calibration requirements, see IEC 60079-29-2.

SC-04 • 3
Table of Contents
Chapter 1: Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
About the SC-04 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
About this Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Chapter 2: Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Instrument Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Case . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
LCD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Control Buttons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Alarm LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Buzzer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Vibrator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Infrared Communications Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Batteries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Standard Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Alligator Clip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Optional Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Watch Band . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Calibration Cup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
IrDA/USB Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Chapter 3: Measuring Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Start Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Turning On the SC-04 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Performing a Demand Zero . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Turning Off the SC-04 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Measuring Mode Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Monitoring an Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Alarm Indications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Responding to Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Data Logging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Chapter 4: Display Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Tips for Using Display Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Peak Screen (PEAK). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
STEL Screen (STEL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
TWA Screen (TWA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

4 • SC-04
User ID Screen (USER ID). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Station ID Screen (STN ID) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Last Successful Calibration Date (CAL.DATA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Last Successful Bump Test Screen (BP.DATA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Date/Time Screen (DATE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Temperature Screen (TEMP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Alarm Points Screen (ALARM--P) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Adjusting the Buzzer Volume (BUZZ.VOL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Chapter 5: User Mode and Calibration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Entering User Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Tips for Using User Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Performing a Bump Test (BUMP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Performing a Calibration (GAS CAL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Setting Calibration Parameters (CAL SET) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Setting Bump Test Parameters (BUMP.SET) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Alarm Settings (ALARM--P) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Updating the Lunch Break Setting (LUNCH) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Setting the Confirmation Beep and Non-Compliance Indicator (BEEP) . . . . . . . . . . . . . 57
Updating the Backlight Time (BL TIME). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Turning the Key Tone On/Off (KEY.TONE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Display Mode Items (DISP.SET) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Zero Suppression (ZERO.SUP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Zero Follower (ZERO.FLW) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Turning Easy Calibration On/Off (E-CAL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Setting the Date/Time (DATE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Turning the Password On/Off (PASS-W) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Viewing the ROM/SUM (ROM/SUM). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Entering Measuring Mode (START) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Chapter 6: Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Replacing the Batteries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Replacing the Sensor Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Replacing the Hydrophobic Filter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Replacing the Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Chapter 7: General Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
Appendix A: Maintenance Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Entering Maintenance Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Tips for Using Maintenance Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Performing a Calibration (GAS CAL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
Performing a Gas Test (GAS.TEST). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
Sensor/Battery Replacement Date (SEN.DATE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

SC-04 • 5
Performing a Bump Test (BUMP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Setting Alarms to Latching or Self-Resetting (LATCH) . . . . . . . . . . . . . . . . . . . . . . . . . 80
Turning the Demand Zero Function On/Off (D.ZERO) . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Turning the Auto Zero Function On/Off (A.ZERO). . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Turning the ID Display Function On/Off (ID DISP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Turning the Zero Suppression On/Off (ZERO.SUP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
Turning the Zero Follower On/Off (ZERO.FLW) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
User Mode Zero Suppression (ZSUP.DSP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
User Mode Zero Follower (ZFLW.DSP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
Cylinder Setting (CYL.DISP). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
Setting the Date/Time (DATE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Turning the Password On/Off (PASS-W) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Viewing the ROM/SUM (ROM/SUM). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Performing a Default (M.DEF). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Entering Measuring Mode (START) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
Appendix B: Gas Select Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
Entering Gas Select Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
Tips for Using Gas Select Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
Saving the Alarm Points (SAVE-AP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
Turning the Calibration Max Span On/Off (MAX.SPAN) . . . . . . . . . . . . . . . . . . . . . . . . 88
Stealth and Vibrator Settings (STEALTH) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
Exiting Gas Select Mode (START). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
Appendix C: Interference Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
ESR-A13D-HCN, HCN Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
ESR-A13D-NO2, NO2Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
ESR-A13D-PH3, PH3Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
ESR-A13D-SO2, SO2Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
ESR-B134-NH3, NH3Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
WARNING: Understand manual before operating. This is an intrinsically safe product.
Substitution of components may impair intrinsic safety. To prevent ignition
of a hazardous atmosphere, batteries must only be changed or charged in
an area known to be nonhazardous. Not tested in oxygen enriched
atmospheres (above 21%).
AVERTISSEMENT:Comprendre le manuel avant de l'utiliser. Ceci est un produit
intrinsèquement sûr. La substitution de composants peut nuire à la sécurité
intrinsèque. Pour éviter l'inflammation d'une atmosphère dangereuse, les
batteries ne doivent être remplacées ou chargées que dans une zone non
dangereuse. Non testé dans des atmosphères enrichies en oxygène (plus de
21%).

6 • Chapter 1: Introduction SC-04
Chapter 1: Introduction
Overview
This chapter briefly describes the SC-04 gas monitor. This chapter also describes the
SC-04 Operator’s Manual (this document). Table 2 at the end of this chapter lists the
specifications for the SC-04.
About the SC-04
Using an advanced detection system, the SC-04 personal gas monitor detects the presence of
super toxic gases like HCN, PH3, and SO2. The SC-04’s compact size and easy-to-use design
make it ideally suited for a wide range of applications, including sewage treatment plants,
utility manholes, tunnels, hazardous waste sites, power stations, petrochemical refineries,
mines, paper mills, drilling rigs, and fire fighting stations. The SC-04 offers a full range of
features, including:
• Liquid crystal display (LCD) for complete and understandable information at a glance
• Ultrabright alarm LED
• Distinctive audible/vibrating alarms for dangerous gas conditions and audible alarms for
unit malfunction
• Microprocessor control for reliability, ease of use, and advanced capabilities
• Data logging functions
• Alarm trend data
• STEL, TWA, and over range alarms
• Peak reading
• Built-in time function
• Lunch break feature
• QPS “C/US” classification for Class I, Division I, Groups A, B, C, and D hazardous
atmospheres
WARNING: The SC-04 detects elevated levels of super toxic gases which can be
dangerous or life threatening. When using the SC-04, you must follow the
instructions and warnings in this manual to assure proper and safe
operation of the unit and to minimize the risk of personal injury. Be sure to
maintain and periodically calibrate the SC-04 as described in this manual.
AVERTISSEMENT:Le SC-04 détecte les niveaux élevés de gaz super toxiques qui peuvent
être dangereux ou mettre la vie en danger. Lorsque vous utilisez le SC-04,
vous devez suivre les instructions et les avertissements de ce manuel pour
assurer un fonctionnement correct et en toute sécurité de l'appareil et pour
réduire les risques de blessures. Assurez-vous de maintenir et d’étalonner
périodiquement le SC-04 comme décrit dans ce manuel.

SC-04 Chapter 1: Introduction • 7
Specifications
Table 1: Standard Sensor Specifications/Alarm Points
Table 2: SC-04 Specifications
Ammonia
(NH3)
Chlorine
(Cl2)
Hydrogen
Cyanide
(HCN)
Nitrogen
Dioxide
(NO2)
Phosphine
(PH3)
Sulfur
Dioxide
(SO2)
Detection Range 0 - 400.0 ppm 0 - 20.00
ppm
0 - 30.0
ppm
0 - 20.00
ppm
0 - 20.00
ppm
0 - 100.00
ppm
Lowest Detectable
Limit (LDL)
4.0 ppm 0.10 ppm 1.0 ppm 0.30 ppm 0.02 ppm 0.20 ppm
Reading Increment 0.5 ppm 0.05 ppm 0.1 ppm 0.05 ppm 0.01 ppm 0.05 ppm
Warning Setpoint 25 ppm 1.00 ppm 5.0 ppm 2.00 ppm 0.30 ppm 2.00 ppm
Alarm Setpoint 35 ppm 2.00 ppm 10.0 ppm 4.00 ppm 0.60 ppm 5.00 ppm
Alarm H Setpoint 300 ppm 10.00 ppm 30.0 ppm 20.00 ppm 0.60 ppm 100.00 ppm
STEL Setpoint 35 ppm 1 ppm 10.0 ppm 1.00 ppm 1.00 ppm 5.00 ppm
TWA Setpoint 25 ppm 0.5 ppm 4.7 ppm 0.50 ppm 0.30 ppm 2.00 ppm
Sampling
Method
Diffusion
Response Time T90 Within 10 Seconds
Display Graphics LCD Display
Operating
Temperature
& Humidity
Continuous environment: -20°C to 50°C/10 to 90% RH
Temporary environment (up to 15 minutes): -40°C to 60°C/0 to 95% RH
Indication
Accuracy
± 10% of reading or ± 5% of full scale (whichever is greater)
Safety/
Regulatory
• ATEX: Certificate Number DEKRA 19ATEX0097
II 1G Ex ia IIC T4 Ga (with alkaline batteries)
II 1G Ex ia IIC T3, Ga (with Ni-MH batteries)
• IECEx: Certificate Number IECEx DEK 19.0059
Ex ia IIC T4 Ga (with alkaline batteries)
Ex ia IIC T3 Ga (with Ni-MH batteries)
• QPS classified, “C/US”, as Intrinsically Safe. Exia. Class I, Groups A, B, C, & D.
Instrument
Power
Information
• Operating Voltage: 3.0V
• Operating Current: 1.0 mA
• Operating Power: 3.0 mW
Power Supply 2 AAA alkaline batteries; 1.5V, 1.175 AH (Duracell MN2400 or PC2400)
OR
2 AAA Ni-MH batteries; 1.2V, 800 mAH (Panasonic Eneloop BK-4MCC)

8 • Chapter 1: Introduction SC-04
About this Manual
The SC-04 Operator’s Manual uses the following conventions for notes, cautions, and
warnings.
NOTE: Describes additional or critical information.
CAUTION: Describes potential damage to equipment.
WARNING: Describes potential danger that can result in injury or death.
Continuous
Operating
Hours
@ 25 °C
Alkaline Batteries: 3,000 hours in Measuring Mode (Non Alarm Operation, Fully Charged)
Ni-MH Batteries: 2,000 hours in Measuring Mode (Non Alarm Operation, Fully Charged)
Case High-impact Plastic, RF Shielded, Dust and Weather Proof (IP67)
Standard
Accessories
• Alligator clip
• Rubber boot
Optional
Accessories
• Belt clip
• Calibration cup
• Datalogging and Setup Programs (Windows®7, 8, and 10), available at
www.rkiinstruments.com/04series
• IrDA/USB Cable for connecting to a computer when using the Datalogging and Setup
Programs (not needed if computer has an infrared port)
Dimensions
and Weight
Approximately 67(H) x 54(W) x 24(D) mm (2.6”H x 2.1”W x 0.9”D)
Approximately 93 g (3.3 oz.)

SC-04 Chapter 2: Description • 9
Chapter 2: Description
Overview
This chapter describes the SC-04 instrument and its accessories.
Instrument Description
Case
The SC-04’s sturdy, high-impact plastic case is radio frequency (RF) resistant and is suitable
for use in many environmental conditions, indoors and out. The case is dust proof and water
resistant. A clear plastic window is located on the front of the case for viewing the LCD. The
sensor retainer is located on the right side of the case and allows access to the filters and
sensor. A feature in the lower left corner of the rear case is used to install the optional wrist
strap.
LCD
A digital LCD (liquid crystal display) is visible through a clear plastic window in the top case.
The LCD shows the gas reading. The LCD also shows information for each of the SC-04’s
operating modes.
Battery Cover Screw
Battery Cover
AIR
SO2
LCD
Buzzer Opening
IrDA Port
Control Buttons Wrist Strap
Connection
POWER
MODE
Diffusion Port
Alarm LED
Figure 1: Component Location

10 • Chapter 2: Description SC-04
Control Buttons
Two control buttons, AIR and POWER MODE, are located below the LCD.
Alarm LED
The alarm LED above the sensor and buzzer openings alerts you to gas, low battery, and
failure alarms.
Buzzer
One solid-state electronic buzzer is located inside the case. Sound exits the case through a
hole in the upper left corner of the front case. The buzzer sounds for gas alarms, malfunctions,
and low battery voltage. It also provides feedback for button presses and while in Display,
User, Maintenance, or Gas Select Mode.
Vibrator
A vibrating motor inside the SC-04 case vibrates for gas alarms and unit malfunctions.
NOTE: If STEALTH is set to ON, the vibrator only functions when VIB in the STEALTH
Gas Select Mode item is set to ON (see pg.89).
Sensor
The sensor is an electrochemical cell that consists of two precious metal electrodes in a dilute
acid electrolyte. A gas permeable membrane covers the sensor face and allows gas to diffuse
into the electrolyte. The gas reacts in the sensor and produces a current proportional to the
concentration of the target gas. The SC-04’s circuitry amplifies the current, converts the
current to a gas concentration, and displays the concentration on the LCD.
Each target gas has its own sensor.
Table 3: SC-04 Control Button Functions
Button Function(s)
AIR • turns on LCD backlight
• resets alarm condition if LATCH is set to ON in Maintenance Mode
• enters User Mode, Maintenance Mode, and Gas Select Mode when used
with POWER MODE
• activates the demand zero function (adjusts the SC-04’s fresh air reading)
• changes the value of a parameter available for adjustment
• scrolls through parameter options
POWER MODE • turns the SC-04 on and off
• turns on LCD backlight
• enters and scrolls through Display Mode
• enters instructions into the SC-04’s microprocessor
• resets alarm condition if LATCH is set to ON in Maintenance Mode
• enters User Mode, Maintenance Mode, and Gas Select Mode when used
with AIR

SC-04 Chapter 2: Description • 11
Filters
NO2and SO2Sensors’ H2S Removal Filter Disk (Tan)
An H2S removal filter disk is placed into a recess in the sensor gasket over the NO2or SO2
sensor. The filter disk prolongs the life of the sensors by preventing H2S in the ambient air
from reaching the sensor. The filter should be replaced every 6 months.
HCN Sensor H2S Removal Filter Disk (Dark Gray)
An H2S removal filter disk is placed into a recess in the sensor gasket over the HCN sensor.
The filter disk prolongs the life of the sensors by preventing H2S in the ambient air from
reaching the sensor. The filter should be replaced every 6 months.
PH3Sensor Humidity Filter (White)
A white humidity filter is placed into a recess in the sensor gasket over the PH3sensor. The
filter absorbs humidity in the sampling environment to prevent unstable readings around 0
ppm. The filter should be replaced every 6 months.
NH3Sensor’s Humidity Filter (White)
A white humidity filter is placed into a recess in the filter gasket over the NH3sensor. The
filter absorbs humidity in the sampling environment to prevent unstable readings around 0
ppm. The filter should be replaced every 6 months.
Hydrophobic Filter
The white, circular hydrophobic filter fits into a recessed area in the front case and is held in
place by the sensor gasket. It prevents water and particulates from entering the instrument.
Infrared Communications Port
An infrared (IR) communications port is located at the top of the instrument, near the LED.
Logged data transmits through the port in standard IrDA protocol. A computer’s infrared port
or an IrDA/USB cable connected to a USB port can be used to download data to the 04 Series
Datalogging Program. See the 04 Series Datalogging Program operator’s manual for data
logging and downloading instructions.
Batteries
2 AAA batteries (alkaline or Ni-MH) power the SC-04. At 25°C alkaline batteries will last at
least 3,000 hours (125 days) and Ni-MH batteries will last at least 2,000 hours (83 days). The
battery icon in the upper right of the LCD shows remaining battery life.
A low battery warning activates when the SC-04 detects a low battery voltage. The SC-04
sounds a dead battery alarm when battery voltage is too low for Measuring Mode.
WARNING: Use only Duracell MN2400 or PC2400 or Eneloop BK-4MCC batteries to
maintain the QPS classification of the SC-04. Use of other batteries will
void the QPS classification and may void the warranty. Do not mix old/new
or different types of batteries.
AVERTISSEMENT:Utiliser uniquement des piles Duracell MN 2400 ou PC 2400 ou
Eneloop BK-4MCC de maintenir la classification QPS de la SC-04.
L’utilisation d’autres piles annule la classification QPS et peut annuler la
garantie. Ne mélangez pas les anciennes/nouvelles ou différents types de
piles.

12 • Chapter 2: Description SC-04
WARNING: To prevent ignition of a hazardous atmosphere, the batteries must only be
changed in an area known to be nonhazardous.
AVERTISSEMENT:Pour éviter l'inflammation d'une atmosphère dangereuse, la batterie
ne doit être remplacée que dans une zone non dangereuse.
Standard Accessories
Alligator Clip
An alligator clip installs to 2 spring bars on the rear case. Use the alligator clip to attach the
SC-04 to clothing or a belt. Teeth in the alligator clip’s jaws prevent slipping. The alligator
clip can be rotated to change the instrument’s orientation.
Protective Rubber Boot
A protective rubber boot is installed over the SC-04.
Open
Alligator Clip
Closed
Figure 2: Alligator Clip
Side Front
Figure 3: Rubber Boot

SC-04 Chapter 2: Description • 13
Optional Accessories
Belt Clip
The belt clip installs to 2 spring bars on the rear case and is used to easily clip the SC-04 onto
a belt.
Wrist Strap
The wrist strap connects to a feature on the back case.
Calibration Cup
The calibration cup installs over the sensor. You must use the calibration cup when performing
a bump test, calibration, or gas test.
IrDA/USB Cable
Unless your computer has a built-in IrDA port, a IrDA/USB cable is needed to establish
communication between the SC-04 and the Datalogging Program or the Setup Program.
Belt Clip
Figure 4: Belt Clip
Figure 5: Calibration Cup

14 • Chapter 3: Measuring Mode SC-04
Chapter 3: Measuring Mode
Overview
This chapter explains how to use the SC-04 to perform confined space entry monitoring or
general area monitoring in Measuring Mode.
Start Up
This section explains how to start up the SC-04, get it ready for operation, and turn it off.
Turning On the SC-04
To illustrate certain functions, the following description of the SC-04 start up sequence
assumes that the following items in User Mode are turned on: LUNCH, CAL.RMDR, and
BP.RMDR in User Mode, and ID DISP and A.ZERO in Maintenance Mode. If any of these
items are turned off, then the corresponding screens do not appear.
1. Press and briefly hold down POWER MODE. Release the button when you hear a beep.
2. If LUNCH is set to ON (factory setting if OFF, see pg.56), the Lunch Break Screen
appears. The unit counts down from 5 seconds.
a. Continue Accumulating: To continue accumulating peak and time-weighted average
(TWA) readings from the last time the SC-04 was used, press and release POWER
MODE or allow the countdown to reach 0. The short-term exposure limit (STEL)
reading is reset each time the SC-04 is turned on.
b. Reset Accumulation: To reset the accumulation of peak and time-weighted average
(TWA) readings, press and release AIR before the countdown reaches 0.
3. If CAL.RMDR is set to ON (factory setting) and a calibration is due, the screen that
appears next depends on how CAL.EXPD is set in User Mode (see pg.50). The three
possible screens are described below. If a calibration is not due, the instrument displays
the number of days left until a calibration is due.
5
SEC
RESUME
5
SEC
YES .MODE
5
SEC
NO .AIR

SC-04 Chapter 3: Measuring Mode • 15
4. If BP.RMDR is set to ON (factory setting is OFF) and a bump test is due, the screen that
appears next depends on how BP.EXPD is set in User Mode (see pg.54). The three
possible screens are described below. If a bump test is not due, the instrument displays the
number of days left until a bump test is due.
CAL.EXPD set to
CONFIRM (factory setting)
CAL.EXPD set to
CANT.USE
CAL.EXPD set to
NONE
LCD
Sound Buzzer sounds double pulsing
tone
Buzzer sounds double pulsing
tone
None
Action • Option A, Perform calibration:
Press and release POWER
MODE to enter User Mode
and perform a calibration. The
instrument takes you straight
to the calibration start screen
in User Mode’s GAS CAL\A-
CAL(E-CAL) item (if
Password Protection is set to
On using the 04 Series Setup
Program, you must enter a
password first). See pg.41 for
calibration instructions.
If the calibration is success-
ful, the screen above will not
appear again until the unit is
due for calibration. If the cali-
bration is not successful, the
screen above will again appear
in the startup sequence.
• Option B, Bypass message: To
continue without performing a
calibration, press and release
AIR.
The SC-04 cannot be used until a
successful calibration is per-
formed. Press and release
POWER MODE to enter User
Mode and perform a calibration.
The instrument takes you straight
to the calibration start screen in
User Mode’s GAS CAL/A-CAL
(E-CAL) item (if Password Pro-
tection is set to On using the 04
Series Setup Program, you must
enter a password first). If you
don’t press POWER MODE, the
instrument automatically goes to
the calibration start screen after 6
seconds (if Password Protec-
tion is set to On using the 04
Series Setup Program, you must
enter a password first). See pg.41
for calibration instructions.
If the calibration is successful,
the screen above will not appear
again until the unit is due for cali-
bration. If the calibration is not
successful, the screen above will
again appear in the startup
sequence.
• Option A, Perform calibration:
If you want to enter User
Mode and perform a
calibration, press and release
POWER MODE. The
instrument takes you straight
to the calibration start screen
in User Mode’s GAS CAL/A-
CAL (E-CAL) item (if
Password Protection is set to
On using the 04 Series Setup
Program, you must enter a
password first).
• Option B, Bypass message:
To continue without
performing a calibration, wait
a few seconds for the
instrument to continue with its
startup sequence.
CAL
CAL - LMT
FAIL
CAL - LMT
0
d
NEXT .CAL

16 • Chapter 3: Measuring Mode SC-04
5. The Date/Time Screen appears for a few seconds.
BP.EXPD set to
CONFIRM (factory setting)
BP.EXPD set to
CANT.USE
BP.EXPD set to
NONE
LCD
Sound Buzzer sounds double pulsing
tone
Buzzer sounds double pulsing
tone
None
Action • Option A, Perform bump test:
Press and release POWER
MODE to enter User Mode
and perform a bump test. The
instrument takes you straight
to the bump test start screen in
User Mode’s BUMP item (if
Password Protection is set to
On using the 04 Series Setup
Program, you must enter a
password first). See pg.37 for
bump test instructions.
If the bump test is successful,
the screen above will not
appear again until the unit is
due for bump testing. If the
bump test is not successful,
the screen above will again
appear in the startup sequence.
• Option B, Bypass message: To
continue without performing a
bump test, press and release
AIR.
The SC-04 cannot be used until a
successful bump test is per-
formed. Press and release
POWER MODE to enter User
Mode and perform a bump test.
The instrument takes you
straight to the bump test start
screen in User Mode’s BUMP
item (if Password Protection is
set to On using the 04 Series
Setup Program, you must enter a
password first). If you don’t
press POWER MODE, the
instrument automatically goes to
the bump test start screen after 6
seconds (if Password Protec-
tion is set to On using the 04
Series Setup Program, you must
enter a password first). See
pg.37 for bump test instructions.
If the bump test is successful, the
screen above will not appear
again until the unit is due for
bump testing. If the bump test is
not successful, the screen above
will again appear in the startup
sequence.
• Option A, Perform bump test:
If you want to enter User
Mode and perform a bump
test, press and release
POWER MODE. The
instrument takes you straight
to the bump test start screen in
User Mode’s BUMP item (if
Password Protection is set to
On using the 04 Series Setup
Program, you must enter a
password first).
• Option B, Bypass message:
To continue without
performing a bump test, wait
a few seconds for the
instrument to continue with its
startup sequence.
CAL
BP - LMT
FAIL
BP - LMT
0
d
NEXT .BP
2020
4.21
10:40

SC-04 Chapter 3: Measuring Mode • 17
6. The Battery Voltage Screen appears for a few seconds. An “AL-L” at the bottom of the
screen indicates that the alarms are set to latching. An “AL-A” at the bottom of the screen
indicates that the alarms are set to auto reset. See pg.80 for a description of how to change
this parameter.
7. The following screens display for 1 second each: Gas Name, Full Scale, Warning Setpoint,
Alarm Setpoint, Alarm H Setpoint, STEL Setpoint, and TWA Setpoint.
8. If ID DISP is set to ON (factory setting is OFF, see pg.81), the User ID Screen appears
for a few seconds, followed by the Station ID Screen.
9. If the SC-04 experiences a sensor failure during start up, a screen indicating that the sensor
failed appears and the buzzer sounds a double pulsing tone once per second.
You cannot acknowledge the failure and continue to Measuring Mode. Replace the failed
sensor as soon as possible.
batt
2.8
AL -L
v
SO2
100.00
F . S .
ppm
CO
2.00
WARNING
ppm
SO2
ppm
CO
5.00
ALARM
ppm
CO
100.00
ALARM H
ppm
CO
5.00
STEL
ppm
CO
2.00
TWA
ppm
USER
ID
U_ID_001
STN
ID
S_ID_001
SO2
FAIL
SENSOR
ppm

18 • Chapter 3: Measuring Mode SC-04
10. If A.ZERO is set to ON (factory setting is OFF, see pg.81), the instrument prompts you to
do an auto zero. An auto zero operation sets the reading to 0 ppm.
WARNING: Make sure that the instrument is in a known fresh air environment (an
environment free of combustible or toxic gases and of normal oxygen
content, 20.9%) before performing an auto zero operation. If you perform
an auto zero operation in an area with gases present, the adjustment will
not be accurate.
You must press and release the POWER MODE button to perform an auto zero function.
If you do not press any key, after 15 seconds, the instrument enters Measuring Mode
without performing an auto zero.
If Password Protection is turned On (factory setting is Off) using the 04 Series Setup
Program, a user-set password is required to perform an auto zero. When the password
screen appears, adjust each digit with the AIR button and press and release the POWER
MODE button to move on to the next digit. Once the password is entered, the instrument
performs the auto zero.
11. The SC-04 is now monitoring for gas in Measuring Mode. The Measuring Mode Screen
displays the current gas reading.
Performing a Demand Zero
Perform a demand zero before using the SC-04. This sets the reading to 0 ppm.
1. Find a fresh-air environment. This is an environment free of toxic or combustible gases
and of normal oxygen content (20.9%).
2. Turn on the unit as described above in “Turning On the SC-04”.
3. Press and hold AIR. The buzzer pulses and the LCD prompts you to continue holding AIR
(if KEY.TONE is set to ON in User Mode).
4. Continue to hold AIR until the LCD prompts you to release it. The SC-04 sets the fresh air
reading. Start up is complete and the unit is now ready for monitoring.
A .ZERO YES .MODE NO .AIR
0000
PASS-W
SO2
0
ppm

SC-04 Chapter 3: Measuring Mode • 19
5. If Password Protection is turned On (factory setting is Off) using the 04 Series Setup
Program, a user-set password is required to perform a demand zero. When the password
screen appears, adjust each digit with the AIR button and press and release the POWER
MODE button to move on to the next digit. Once the password is entered, the instrument
sets the fresh air reading.
Turning Off the SC-04
1. Press and hold POWER MODE.
2. OFF appears on the display and the buzzer pulses for about five seconds (if KEY.TONE
is set to ON in User Mode).
3. Release the button when OFF disappears from the display.
4. If Password Protection is turned On (factory setting is Off) using the 04 Series Setup
Program, a user-set password is required to turn off the SC-04. When the password screen
appears, adjust each digit with the AIR button and press and release the POWER MODE
button to move on to the next digit. Once the password is entered, the instrument shuts off.
Measuring Mode Operation
When the SC-04 completes its startup sequence, it is in Measuring Mode. In Measuring Mode
the SC-04 continuously monitors the sampled atmosphere and displays the gas concentration.
The SC-04 is in Normal Operation if there are no alarm indications.
Heart Symbol: The heart symbol in the top right corner of the LCD indicates the operation
status and flashes when normal. A microprocessor error causes the heart symbol to stop
flashing or to disappear.
Check Mark: If BP.RMDR is set to ON and if a bump test is not due, a check mark appears in
the lower left corner of the LCD.
“S”: If the instrument is operating in Stealth Mode, an “S.” appears at the bottom of the LCD.
Backlight: In a low-light environment, press and release either button to turn on the display
backlight. See pg.58 to program backlight duration.
Confirmation/Non-Compliance Indicator: If the BEEP item in User Mode is set to anything
other than OFF, the SC-04 gives periodic indications to confirm that it’s operating or to
indicate a non-compliance (see pg.57).
0000
PASS-W
0000
PASS-W
SO2
0.00
S.
ppm

20 • Chapter 3: Measuring Mode SC-04
Monitoring an Area
1. Start up the SC-04 as described above in “Start Up” on page 14. It is now in Measuring
Mode.
2. The instrument displays the gas reading.
3. Take the SC-04 to the monitoring area.
4. Wait at least 15 seconds.
5. If a reading is observed, allow the reading to stabilize to determine the gas concentration
present.
6. If a gas alarm occurs, take appropriate action. See pg.22.
Interference Information
Some gases interfere with the super toxic sensors. For a complete list of these gases, see
pg.90.
Alarms
This section covers alarm indications in Measuring Mode. It also describes how to reset the
SC-04 after an alarm occurs and how to respond to an alarm condition.
NOTE: False alarms may be caused by radio frequency (RF) or electromagnetic (EMI)
interference. Keep the SC-04 away from RF and EMI sources such as radio
transmitters or large motors.
Alarm Indications
The SC-04 buzzer sounds an alarm, the LED flashes, and the vibrator pulses when any sort of
alarm condition or failure occurs. If the SC-04 is operating in Stealth Mode, the buzzer does
not sound and the vibrator’s operation depends on the VIB setting in Gas Select Mode’s
STEALTH item. See pg.89 for more information.
NOTE: If an alarm condition occurs while you are in Display Mode, the SC-04
automatically returns to the Measuring Mode screen.
The table below summarizes the types of alarms produced by the SC-04 and their indications.
Table 4: Alarm Types and Indications
Alarm Type Visual Indications Other Indications
Warning
Concentration of gas rises above the
Warning setting.
• Gas reading flashes
•WARNING appears at the bottom of
the LCD
• Alarm LED flashes once per second
• Backlight turns on
• High-low tone sounds
once per second
• Vibrator pulses once per
second
SO2
0.00
ppm