what are two types of smoke curtain -Horizontal type

There are two types of smoke curtain: Vertical smoke curtain and Horizontal smoke curtain.

Horizontal smoke curtains 

The Horizontal smoke curtain are suitable for a building which has an atrium, loft or very high ceilings, to install smoke curtains can help prevent smoke from rising upward in the building, spreading to other areas above.  Smoke and heat rise, so a fire that breaks out on a lower floor will have smoke that begins to rise long before the flames do.

A horizontal smoke curtain seals off upper floors and areas that smoke would flow to . This type of curtain also make smoke ventilation system easier to work ,because it can help direct smoke to vents or exhausts instead of letting it spread freely.