Loyalist College

Loyalist College has chemical lab hood & fume arm ventilation addressed by O'Dell Associates.

O'Dell Value ...

O'Dell offered an uncompormising & economical solution to maintain a safe working environment for Loyalist College's new laboratory.  Student & professor safety was Paramount!  

The Call ...

Dordan Mechanical was doing the base building work for construction of a new wing at Loyalist College.  The classroom spaces were ear-marked to accommodate fully operational laboratories.  The labs would require ventilation of numerous laboratory hoods and point source extraction.

With our comprehensive ventilation offering, and HVAC system expertise, O'Dell was contacted to deliver a cost effective solution for the labs that would provide students with a safe working environment.  

The Solution ...

The lab hoods and the desktop ventilation requirements were addressed separately. 

Lab Hood Design

The lab hoods were installed in two main classrooms, Wet Lab 1 and Wet Lab 2, with six (6) and four (4) hoods respectively.  Each hood operated at two different exhaust levels depending on the sash height.  This required a variable exhaust airflow solution for each hood and classroom. 

From each hood, the airflow is controlled by a Krueger model RVE 316 stainless steel terminal unit complete with SS airflow sensor.  At the heart of the terminal unit is a Belimo VFP-600 airfow sensor, VRP-M controller & fast acting (2 sec. stroke) LMQ24-MFT actuator.  The complete Belimo package is easily commissioned & customized on site with a user friendly software package.   

Exhaust for the lab hoods was provided by a single dedicated PennBarry FH exhaust fan in each classroom.  The fan was complete with a bypass plenum to allow for variable exhaust airflow from the classroom while maintaining an acceptable discharge plume height.  The dampers on the bypass plenum are controlled by a Honeywell controller and Greystone static pressure sensor located in the main exhaust duct.

Desktop Ventilation

The complete desktop ventilation system was provided by Plymovent, and consisted of fume arms, pressure controls (similar to lab hoods) and VFD driven direct drive exhaust fans.  Four separate desktop ventilation systems were installed in four classrooms within the facility,  with six (6), thirteen (13), twelve (12) and four (4) fume arms respectively.   

Each user workstation was provided with a MINIMAN-75, 3" exhaust arm, complete with isolation damper.  When the system is in use, the student opens the damper to provide adequate ventilation over their experiment. 

As dampers throughout the system open & close, the static pressure in the main exhaust duct for the classroom changes.  Similary to the lab hood controls, this pressure is monitored and the exhaust airflow is modulated via a VFD to maintain a preset value.