Ammonia & Hydrogen Sulfide Dual Breakthrough Indicator for carbon scrubbers and filters

Filter Replacement Indicator

Item No. 192

Ammonia & Hydrogen Sulfide BTI

(3.5” x 1”, ¾” male NPT)

The Ammonia & hydrogen Sulfide Breakthrough indicator for Carbon Scrubbers and Filters is a colorimetric indicator that indicate the saturation and exhaustion of carbon scrubbers. The indicator is reliable and cost effect means for protection from exposure to toxic ammonia & hydrogen sulfide gases in the work place. The indicator change color from yellow to blue or black when carbon scrubbers are saturated with ammonia and/or hydrogen sulfide. Hence alerting the user to replace the exhausted carbon scrubber or filter. The indicator is easily connected to the ¾ inch female NPT outlet of the carbon scrubber or filter using the ¾ inch male NPT threading at the bottom of the indicator. It is highly sensitive to ammonia and hydrogen sulfide.

It operates at temperatures -20oC to 65oC (-4oF to 149oF) and humidities 5% RH to 95%RH. The indicator is 3.5 inch tall, 1 inch diameter and you can observe the bright vibrant color change from all directions. The unique design of the indicator prevents any color change due to exposure to contaminants in the surrounding environment and changes color only when carbon scrubber or filter is saturated. The indicator has extended service life of 2 years.

Product Specifications



28g (1.0oz)



89.9mm (3.5in), diameter 24.5mm (1.0in)


Inlet dimensions:



Operating temperature:

-20oC to 65oC (-4oF to 149oF)


Operating humidity:

5% RH to 95%RH


Minimum detectable limit:

10ppm•hr  for ammonia and or 1ppm•min for hydrogen sulfide at 30 cm/sec face velocity


Color change:

Light blue to purple or black


Storage temperature:

4oC to 25oC, (39oF to 77oF)


Shelf life:

2 years at 4oC to 25oC, (39oF to 77oF)


Service life:

2 years

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