Carbon Dioxide Scrubber Systems for Tunneling

Strata carbon dioxide scrubbers, are active, stand-alone systems designed to remove CO2 and maintain safe breathable air in enclosed areas.
Powerless carbon-dioxide scrubber

Strata scrubbers have built-in fan systems that actively draw air into the scrubber and push it out through soda lime cartridges to scrub the CO2, Over time, the cartridges need to be exchanged and a schedule, based on the number of occupants, for this change-out, is provided in the chamber. Strata scrubbers maintain CO2 levels below 10,000 ppm (1%).

  • Single scrubber suitable for 0-30 persons
  • Multiple scrubbers required for more than 30 persons


SodaSorb™ Cartridges

Strata SodaSorb™ Cartridges are specifically designed to eliminate spillage and airborne dust particles from the soda lime. They are easy to store and easy to handle with compact packaging that prevents “channeling” of the chemicals.

  • Weight: 37lb (17kg) per cartridge
  • Dimensions: 16” x 12” x 6.5”
Strata Emergency Refuge Chamber Interior
Strata ActiveAir™ Powered Scrubber


The Strata ActiveAir™ scrubber is connected to the chambers main power source. Either mine power or the chamber battery back-up. Standard battery life is 48 hours (scalable). There is also an optional stand-alone power station with dedicated batteries for the scrubber.


Low pressure oxygen cylinders equipped with individual flow-rate meters regulate the release of oxygen into the environment. These are set according to the number of occupants and provide up to 5.5 LPM distribution per oxygen cylinder. It is imperative to maintain oxygen levels between 19 and 22.5%.


Atmospheric Monitoring

Incorporated into the design of the ActiveAir scrubber are Trolex Sentro 1 gas monitors which continuously monitor CO2 and O2 levels. If gas levels rise or fall to dangerous levels, the sensors emit audible and visual alarms to alert the occupants.


Change-out Timer

A built-in timer, set according to the number of occupants, is included to alert occupants when cartridge change-outs are recommended.


gas detection in refuge chamber