1. What is Ventilation?
There is often confusion about what ventilation actually means. Ventilation is the introduction of fresh outside air to a room and the removal of contaminated air to the outside. It should not be confused with air conditioning, air filtration or air cleaning.

Ventilation is required for all occupied spaces. Although air conditioning, air cleaners and filtration systems can be used in conjunction with ventilation plant, they do not generally contribute to the Air Change (ACH) rate per hour. Here are some basic examples:

Ventilation

• Air Handling Units, Heat Exchangers, etc
• Brings in fresh outside air and extracts stale air
• They also dilute and remove gases including carbon monoxide and other hazardous substances

Air Cleaning/Filtration

• Usually a cassette unit on the wall or ceiling
• Removes particles from the air
• They can sometimes remove some gases through carbon filter

Air Conditioning

• Simply heats, cools and or humidifies the air. Some systems also supply a small amount of fresh air
• Recirculates air already in the room and does not usually provide fresh air (although in some systems 15-20% fresh air)

2. Are there different types of Ventilation?
Yes, there are three main types. These being:

• Natural Ventilation (e.g. windows, vents in walls/roof spaces),
• Mechanical Ventilation Air is supplied and extracted from the space using fans
• Mixed Mode Ventilation (combination of natural and mechanical ventilation to suit building’s needs).

3. How much will it cost?
Cost depends on type of ventilation, amount of ductwork (if any), and degree of difficulty of installation.

4. What size of unit will I need?
Various sizes (flow rates) are available. The right size unit depends on the number of occupants and the cubic capacity of the area to be ventilated.

5. Does it reduce odours?
Yes. The continuous flow of fresh air and the removal of contaminated air dilute gases and reduce the concentration of particles in the space.

6. How long will installation take?
This is entirely dependant on the size and degree of the job.

8. How often should a ventilation system be maintained?
Sigma recommends that your ventilation system should be maintained at least once a year. Filter change etc. is dependant on contamination level, intensity of use etc.

9. What are the health benefits?
100% fresh filtered air is brought into the venue while the volatile organic compounds (VOCs) are removed, reducing the risk of respiratory illnesses.

10. Is it possible to heat the air?
Yes. Incoming air can be warmed naturally using Sigma’s patented Heat Recovery Core. Alternatively an electrical Heater Battery can be fitted in the unit.

11. Where can they be fitted?
Our flexible manufacturing systems allow us to custom make the unit to suit your venue. Units are easily fitted into new builds or retrofitted in existing premises (even Listed Buildings). It is recommended that we carry out a survey in order to put forward a fully costed proposal.

12. Who fits the system?
Sigma or a preferred installer.