Cal Check, LLC
11600 Black Horse Run, Raleigh, NC 27613
p: 919.847.1898    f: 919.847.8005    e:
smoke stack testing

Cal Check Advantages:

  • Meets new PS1 Requirements (ASTM D6216-03)
  • Helps comply with regulations
  • Isolates the monitor from stack
  • On-stack testing using filters
  • Unparalleled customer support and service


   • Test Filters
   • Cal Check 101Z
   • Cal Check 101
   • Cal Check 301
   • Cal Check 401
   • Cal Check 402
   • Cal Check 501
   • Cal Check 701

Cal Check Products and Services

Cal Check offers top quality opacity monitor test equipment for a single opacity monitor or an entire CEM network. We are your single source to fill all your on-stack or off-stack opacity testing needs. We also offer on-site training, NIST Traceable certification and inspection, prompt notification of problems, and annual reminders. Click below for more information about our products.

Test Filter Certification Services

The accuracy of opacity monitor testing is limited by the accuracy of the filters used for testing. Since opacity filters can change over time, we recommend annual testing to ensure correct results. All of our test results are traceable to the National Institute of Standards and Technology (NIST) reference materials. All certifications are performed in our laboratory with state of the art analysis equipment. We also certify smoke generator and diesel emission meter filters.

Cal Check Test Filters:

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view test filter details

Opacity Monitor Test Equipment:

Cal Check 101Z Cal Check 101 Cal Check 301 Cal Check 401
Cal Check 101Z
(LSI RM41/4200 & Land 4500 Mark I)
Cal Check 101 Cal Check 301
(Durag/Enviroplan 280/281)
Cal Check 401
(LSI/Dynatron 1100 & 1100M)

Cal Check 402

Cal Check 501

Cal Check 701
Cal Check 402
(Monitor Labs ML541)
Cal Check 501
(United Sciences 500C & TECO M400)
Cal Check 701
(SICK Maihak OMD41)