Esco Ascent max, User And Service Manual

Page: 35 / 71

25
Ductless Fume Hoods
Chapter 6–Recertification & Calibration
Ductless fume hood generally require re ‐ certification, when:
•
The hood is re ‐ located
•
Hood’s performance is suspected
•
After filter or blower replacement
•
At least once a year
During recertification:
•
Cabinet airflow velocities and flow patterns are verified against the manufacturer’s specifications and
relevant international standards
•
Filters are scan ‐ tested to ensure they do not leak
•
Operator comfort tests may be performed
•
If airflow velocities are found to be off set point, adjustments are made as part of the certification
process before final values are recorded.
Airflow alarm calibration, when:
•
The cause of the airflow alarm cannot be determined
•
Re ‐ certification indicates the displayed airflow deviates by >0.02m/s (4fpm) from actual measured
velocities.
6.1 Certification Flowchart