Opera 6000 Series Operation Manual page 9

at 3 to 5 feet (1 to 1.5 meters) from the floor as per the
requirements of the Canada building codes and the nitrogen
dioxide monitors should be installed at 50% of the ceiling
height and above the vehicle height. If the exhaust pipes
of diesel vehicles are below the vehicles, then the nitrogen
dioxide monitors should be installed at 3 to 5 feet (1 to 1.5
meters) from the floor. In all cases the monitors must be
installed above obstructions blocking circulation of air in
front of the monitors; example, maintenance garages in
automobile dealerships where tool chests, work tables and
storage racks typically line all walls.
3. Heavier than air and will concentrate near the floor; - HFCs,
HCFCs, propane, chlorine, most organic vapors (consult
Opera). Install 1-2 feet (30cm to 50cm) from floor.
For all types of monitors avoid drafts, obstacles, aerosols, silicones.
Place sensors in the center of its coverage area as much as
possible.
3.0 Installation