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Estimation of Service Life by Breakthrough Curve

Service life of cartridge varies depending on the gas concentration in the environment.
Breakthrough curve represents the relationship between the gas concentration level in the environment and estimated service life.

How to Read
Measure the gas concentration level in the environment and plot it on the Y-axis on the breakthrough curve. Draw an extension line from that point, parallel to the X-axis towards the breakthrough curve. The estimated service life is the value on the X-axis where the extension line meets the curve. For example, with the cyclohexane concentration of 300ppm, the estimated service life of KGC-1M(C) cartridge is 200 minutes (under temperature of 20 and relative humidity of 50%). With the cyclohexane concentration of 500ppm, the estimated service life is 95 minutes (under temperature of 30 and relative humidity of 70%). If the cartridge is repeatedly used, and used for a short period of time in each occasion and the gas concentration level in the environment remains constant, record the used time in the “Record of used time” column on the user instruction of the cartridge and replace the cartridge with a new one when the accumulation of the used time reaches to the estimated service life.


>Estimation of service life using the breakthrough curve is just for reference purpose only. Service life varies depending on various factors.

>Decontamination performance of the cartridge may remarkably decrease unless used under normal temperature and/or normal humidity.

>Residual service life of organic vapor cartridge, if used for more than half of its estimated service life and stored for 5 days or more, may become remarkably short. Replace the cartridge well in advance under this condition.

Estimation of service life other than by breakthrough curve
Estimation of service life by smell
It is dangerous to judge only by smell. Smell can be used as a tool to judge for replacement if it can be sensed below the permissible exposure limit of the gas. Sense of smell can vary between individuals, and it can get paralyzed if the gas leaks gradually.

Estimation of service life by inhalation resistance
Replace the cartridge with a new one when the inhalation resistance increases (when the wearer feels difficulty in breathing), regardless of decontamination capability remaining.
  Estimation of service life by particulate-removing performance
(applicable when the cartridge with a particulate-removing
feature is used).
Replace the cartridge with a new one when:
*the particulate filtering efficiency gets decreased; and/or
*the filtering material gets damaged or distorted.
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