(1) Calibration cycle: pre calibration before shipment. First calibration after 2 years of low density; Then perform abnormal calibration in the third and fourth years. Note: The product will continue to operate until its shelf life, but performance may not be ideal (e.g., accuracy or measurement range may be smaller - but the product will continue to operate)

(2) Calibration Process/Method: Three options are available:

2.1 - Customers can purchase new gas modules to replace existing modules that no longer meet accuracy or range requirements. The customer can replace it on site. Customer monitoring service will not be interrupted

2.2 - Customers can ship back existing defective modules; Polysense will recalibrate the cost; Customers will have a period of service interruption (4-6 weeks)

2.3 - The customer can recalibrate the defective module. But customers need to establish a recalibration environment and have the instruments - both can be expensive.

Most of our customers use #2.1 most often, and some also use # 2.3 (usually these customers have researchers present).