How to check the capacity of ventilation fans

Why measure fan capacity?

● If fan capacity is impaired, ventilation will be inadequate, and

   bird performance may be affected.

● Measuring air speed through the fan or measuring fan revolutions per

   minute (RPM) will determine whether or not fans are working correctly

   and are in line with manufacturers’ specifications.

Procedure for measuring fan capacity

● Step 1– Open all air inlets and doors fully.

● Step 2– If fan blades are plastic, a reflective sticker will need to be placed approximately 

   5 – 7 cm (2 – 3 in) from the tip of the blade.

● Step 3– Turn on the fan to be tested. All fans should be tested individually and at full    

   speed.

● Step 4– Holding the meter still 0.6 – 1.0 m (2 – 3 ft) away from the fan and at a slight

   angle, point the laser at the sticker or directly at one blade if the blades are reflective /

  metal, until the reading on the tachometer becomes constant. Note: If the fan has        

  reflective / metal blades, the recording on the tachometer must be divided by the number

  of blades the fan has. The RPM should be within the manufacturer’s guidelines or the

  guidelines set by an independent testing facility.

● Step 5– Compare fan RPM with manufacturers’ specifications.