G7c Overview


G7c is the world’s first 3G-connected gas detector with integrated lone worker monitoring and evacuation management tools, connecting workers to live monitoring personnel in real-time. Work-anywhere 3G connectivity is complemented by an industrial two-way speakerphone, text messaging and location tracking.

Devices automatically watch over workers and call for help, even when the employee can’t. G7c delivers comprehensive gas coverage with an exclusive modular design, tailoring gas detection to every industry, application and scenario. Should a gas leak, fall or a no-motion incident be detected, assisted-GPS capability guides responders directly to the effected worker’s location.

G7c provides critical insights and situational awareness for optimized emergency responses, enabling teams to react with all the information necessary for rescues in complex, hazardous environments. Devices communicate all gas detection and safety incidents to live monitoring teams who can mobilize responders to an employee’s exact location or trigger evacuations in real-time when required.

If you are using G7c for gas detection, you can review your device’s bump test and calibration certificates here.


How long will my battery last?

G7c has a battery life of 18 hours continuous operation at 20°C (68°F).

How long does calibration or bump test take?

Calibrations take about four minutes, while bump tests take around 30 seconds. The exact time may differ depending on the gas being used.

Can I make calls with G7?

G7 can receive calls from monitoring personnel, but cannot make them. If you need to request help, please pull the red latch.

What is the difference between standard, single an quad-gas cartridges?

Standard cartridges do not support gas detection, single-gas cartridges support the detection of your choice of one gas and quad-gas cartridges support the detection of your choice of four gases.

What is the difference between yellow pending alarm, yellow warning alarm and red alerts?

Yellow pending and warning alarms are between you and G7, and are not communicated to monitoring personnel. Yellow pending alarms can escalate into red alerts if they are not cancelled within the configured time period, whereas warning alarms will never escalate. Red alerts are immediately communicated to the Blackline Live portal and monitoring personnel, and can only be silenced– not cancelled.

How do I change which gas(es) G7 detects?

G7’s cartridge can be changed by removing the two screws on either side of the cartridge and pulling upward. To add a new cartridge, slide the cartridge onto G7 and replace the screws. If you wish to order new gas cartridges, please contact Blackline’s Customer Care team.

I can't silence my alarm, what should I do?

Look at G7’s screen to ensure that you are performing the correct action. If you are pressing on the up and down arrows, ensure that you are applying constant pressure.

When G7 goes into alert or alarm, I'm not sure what is wrong. How do I know?

If you are not sure why G7 is making noise, the LCD screen will inform you of the reason and provide further instructions.

Does G7c have latching alarms?

Blackline provides a more advanced method of latching than traditional gas detectors. The device itself does not “latch” – it shows the current status of the gas reading so that the user has the best and most accurate information available to them.

However, high gas alerts are latched in our portal. These alerts are persistent even when the gas clears. Monitoring personnel will follow the company’s custom protocol before resolving the alert.

If I have a G7 with a single gas Oxygen (O2) cartridge, can I bump and calibrate with my breath?

Yes, the G7 supports bumping and calibrating with your breath. Here’s an explanation of how it works:

During an instrument calibration, the output of each gas sensor must be measured at two points. Those two points are called “zero point” and “span point”. Zero point represents the output of the sensor in the absence of gas and span point represents the output of the sensor at a higher, known concentration of gas.

The ambient environment does not contain the target gas for most gas sensors so ambient air can used to measure the zero point during calibration. Then a known concentration of the target gas is applied to the sensor to measure the span point. After these two points have been measured and confirmed to be within the acceptable limits, the calibration can be applied to the instrument.

Oxygen sensors are an exception to what is described above. The ambient air contains 20.9% of the target gas, oxygen, so it cannot be used to measure the zero point . For oxygen sensors the zero point is assumed to be when the sensor has zero output. Ambient air is used to measure the span point at 20.9%. Using those two points the calibration is calculated but it is not immediately applied to the instrument. The sensor has not yet been tested to ensure that it responds when the concentration of oxygen changes. To confirm the operation of the sensor a gas that has a concentration of lower than 19.5% must be applied. If the sensor responds appropriately to the drop in oxygen then the previously calculated calibration is applied to the instrument.

Bottled calibration gas for oxygen sensors will typically contain 18% oxygen. This gas is used during the calibration process to test the that the oxygen sensor responds appropriately but is not actually used in the determination of a zero or span point. Because exhaled breath only contains about 15% oxygen, an oxygen calibration can be completed by breathing on the sensor.

How do I bump and calibrate a chlorine gas sensor?

Chlorine is unique in that it is a sticky gas — it adheres to surfaces it has contact with, causing it to release slower than other gases. When bump testing or calibrating chlorine keep the following tips in mind:

  1. Use our stainless steel 1.0L fixed flow regulator (ACC-REG-1L) instead of our regular 0.5L regulator. ONLY use the 1.0L regulator with chlorine gas.
  2. Use teflon-lined tubing. Our chlorine sensors are shipped with special tubing (Versilon SE200).

G7 dock does NOT support chlorine gas. DO NOT use dock to bump test or calibrate chlorine sensors.

Support Materials


G7 the Future of Connected Safety and Gas Detection

How to bump test G7 with a balloon adapter

Resource Library

G7c Datasheet