VPE 511: Environment and Environmental Hygiene (2+1)

STANDARDS OF VENTILATION

• The standards of ventilation have been based on the efficiency of ventilation in removing odour and obnoxious gases. The gases generated are mainly CO₂ , NH₃, H₂S, methane, CO and fumigation gases like HCHO, etc. The threshold limit value for animals is lower than that for man and deserves utmost attention. Three standards are considered for ventilation.
  • Cubic space: The air of the animal house would appear fresh as long as the amount of carbon dioxide produced during respiration does not exceed more than two parts in 10,000 parts of air. This would depend on the type, age, and number of livestock housed therein.
  • Air change: It is more important than the cubic space requirement because the cooling effect power of the air is to be maintained satisfactorily. The number of air changes per hour is calculated by dividing the total hourly air supply to the house by the cubic capacity of the house.
  • Floor space: the floor space per animal is more important than the cubic space. Height in excess of 3 meters is ineffective from the point of view of ventilation as the products of respiration tend to accumulate at the lower levels.