In large roofs, ventilation can be improved with ridge ventilators.
Heating is effected by means of hot-water pipes below the beds, and against the side ventilators.
A genial moist atmosphere must be kept up in the hottest houses during the growing season, with a free circulation of air admitted very cautiously by well-guarded ventilators.
Replacement windows should be fitted with trickle ventilators, or an equivalent background ventilation opening should be provided in the same room.
With most other gas driven ventilators, the volume of driving gas required is equal to the patient's minute volume 7 & 8.