FOG & HAZE

1. FOG & HAZE Looking into understanding fog and its various applications. Presenter: Thierry Pouliot

2. What is Fog? • Meteorological phenomenon • Water droplets • Fine ice crystals • Near-freezing air temperature • Water saturation

3. How does it happen? • 3 common types of fog • Advection fog • Radiation fog • Evaporation fog

4. Advection Fog • Vapor condensation around dust particles • Warm air blown across a cool surface, like wind from the ocean • Creates fog

5. Radiation Fog • Cool Ground • Warm air • Vapor condensation around dust particles • Creates fog

6. Evaporation Fog • Additional water vapor enters an already saturated air near maximum vapor pressure (Kpa) The air is cooled down to dew point • Creates fog

7. Comes mostly from water evaporation and stagnant particles Is affected by air temperature, barometric pressure, wind speed and water saturation. May come from pollution! Comes from various chemicals and processes Is affected by air temperature, barometric pressure, wind speed and water saturation. May cause pollution! Natural fog vs Artificial fog

8. Creating artificial fog Creating fog requires 3 key elements: A Method of production Some form of chemical compound Ambiant air support

9. Methods of production • Fog / Haze Generator • Fog / Haze Machine • « Cracker » • Others

10. Quiet! Constant output 100% duty cycle Gas used as: Non-flammable propellant Purge Fog dispersion Louder Pressure variation Sometimes needs a pause to reheat. No gas required Fog Generators vs Fog Machines

11. « Crackers » • Thermal cracking: petrochemical industry…

12. … or the nuclear

13. So, « Crackers »? • Cracking modifies chemicals at the molecular level • Cracking requires very high operating temperature and / or pressure

14. Artificial fog chemical compounds

15. Mineral oil-based fluid • MDG Neutral (suitable for standard MAX™ and ATM™ series). • Odourless and insipid. • Produces fine particles (0.5 ~ 0.7µm) • Long hang time (Brownian Motion) – low gravitational pull • Low coalescence, high dispersion.

16. Mineral oil? • Inert, non-reactive, non-irritant • Used as a medically-supervised laxative • Main ingredient in Baby oil / lotions • Cosmetic cold creams, make-up remover • Used as a machanical lubricant / coolant • Used as a preservative (lithium) and oxydation inhibitor (nihontō) • Aka - Paraffin, Petrol gelly

17. Glycol-Based fluid • MDG LOW FOG fluid (suitable for standard Ice-Fog™ series) and MDG DENSE or WB2 fluid (suitable for standard MM™ series). • Distinctive smell, acrid taste • Produces larger particles (2.5 ~ 20 µm) • Variable hang time • Higher coalescence, high dispersion.

18. Glycol? • 2 main types used in fog: Diethylene and Propylene Glygols • Hygroscopic compound • Fast heat dissipation

19. Other uses of Glycols • Industrial coolant • Automotive coolant • Anti-perspirant • Componant in the manufacturing of resins, polyesters, explosives, and vaccines • Used as a preservative to replace formaldehyde.

20. Safety Standards • Using your fog machine / cracker / generator • NEVER NEAR PEOPLE • Most fog machines operate either under pressure or at high temperatures. • Most fogs are still in a liquid state (Wet Fog) • Most fogs are hot near nozzle / exit port • ALL FOGS LEAVE RESIDUES

21. INERT GASES • Unlike Noble gases, Inert gases are not necessarily elemental. • Most are compounds • Complete valence electron (last orbit full) • Inert gases: Helium and Neon (elemental) Carbon Dioxide (CO2)and Nitrogen (N2)

22. Inert gases usage • Non-flammable • Readily available everywhere • Relatively cheap • Standard safety code throughout the EU

24. Fog applications: • First Response Training

25. Final tip of the day • LESS IS MORE