MRK-D-0034 V2.0
Aeroqual AQM 65 User Guide
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4.5 Factory calibration of Particle Monitor and Particle Profiler
Dust and other debris can settle upon the internal optics of the optical engine which can lead to
inaccurate readings. The laser and detector may also need to be replaced.
The Particle Monitor optical module (nephelometer) requires a factory service and calibration every
two years.
The Particle Profiler optical module (optical particle counter) requires a factory service and calibration
every year.
Contact
for information about factory service and calibration of the Particle
Monitor and Particle Profiler.
4.6 Service frequency guidelines
The frequency of some of the service activities described above can depend upon environmental
conditions and also upon data quality objectives. Some service activities are required at fixed
frequencies (
scheduled maintenance
), and some are performed only as required (
unscheduled
maintenance).
Service intervals will vary depending on site conditions. For instance, particulate matter levels will
impact the frequency of filter changes
– high PM levels = more frequent filter changes
It is important to change the filter when it gets dirty. Once the local site conditions are understood, a
filter change schedule can be developed for that site.
Figure 4-38 Filters should be changed before they get too dirty. The frequency of filter changes will
depend upon local site conditions.
Data quality objectives will also influence the service frequencies for some operations. In monitoring
situations where data quality objectives are high, for example where monitoring is performed for
compliance or where a high amount of scrutiny will be placed on the data, service frequencies may be
higher.
It is recommended that the instrument engineer, over time, develops an appropriate servicing
schedule for a particular site.
Table 4.1 provides guidelines for service frequencies for the service activities documented in this user
guide.