Special effects equipment is essential for creating atmosphere at stage performances, celebrations, weddings, and other events. As common special effects equipment, smoke machines, mist machines, and dry ice machines have similarities, but also unique principles and application scenarios.
Working Principle
Fog/Smoke machine
Fog machines and smoke machines operate on a similar principle: both use a specialized fluid—typically a mixture of purified water, ethanol, and glycerin—that vaporizes when heated, producing a dense white smoke or a fine mist. The words "smoke" and "fog" are often used interchangeably, with smoke machines/fog machines producing thicker smoke and being more suitable for creating a strong visual impact.
The density of the output depends on the oil concentration in the fluid—higher oil content produces thicker smoke. That said, larger fog particles tend to condense more easily on surfaces, including lighting equipment and stages. This can be especially problematic in enclosed spaces like KTV rooms, where oily residue builds up inside the machine and on cooling fans, making cleaning more difficult.
Despite these maintenance considerations, fog machines are widely valued for their ability to create dramatic, highly visible effects—even from a distance—making them a popular choice for evoking atmospheres like haunted castles, alien planets, or mysterious nights.
Haze machine
Haze machines (sometimes called mist machines) work by heating haze oil and then blowing it through a fan. This creates a thin layer of fog that fills the space, providing an ideal backdrop for projected images and diffused light in television productions.
This fine mist also helps create more realistic stage sets while maintaining focus on intricate details without obscuring the entire stage. Haze machines are popular for those who want to create depth and add dimension to lighting without obstructing the view. They are also well-suited for laser light shows.
Dry ice machine
Dry ice machines work differently. They use solid carbon dioxide—dry ice—which quickly evaporates into gaseous carbon dioxide when it comes into contact with hot water. Because carbon dioxide is denser than air, the smoke from a dry ice machine settles to lower levels, typically rising only to below the knees. This makes it ideal for creating a blanket of smoke.
The downside is that dry ice is difficult to store and is not suitable for, and therefore dangerous to, freezers. Because the dry ice is much cooler than the temperature inside the freezer, it releases heat, and a freezer is a sealed space.
Low fog machine
Low fog machines are a subtype of fog machines. They heat the smoke, which then passes through a low-temperature ice-water mixture and is released. Due to the low temperature, the smoke doesn't rise, but instead stays on the ground.
Low fog machines use heavy smoke oil, but they produce the same ground-hugging smoke effect as dry ice machines.
The difference
The differences between fog machines, smoke machines and dry ice machines are:
1, Odour: Fog and smoke machines will have some odour, The smell of smoke from a haze machine is lighter than that from a fog machine, dry ice machines consume dry ice, so dry ice machines have no odour at all.
2, Dissipation Time: The effects produced by fog and smoke machines last significantly longer than those from dry ice machines. Dry ice machines use solid CO₂ as a consumable, which causes the smoke to dissipate much more quickly. In comparison, the smoke generated by haze machines dissipates the fastest among all.
3,Consumables: Fog machines and smoke machines both use fog oil; low fog machines use heavy smoke oil; haze machines use water-based haze liquid, and one upward-spraying haze machine uses oil-based haze liquid; dry ice fog machines use dry ice.
The difference between water-based and oil-based liquids is that water-based liquids require heating, while oil-based liquids do not.
Usage Scenarios
Fog machine
Fog machines/Smoke machines are a popular choice for intensifying the atmosphere at concerts, parties, and music events, where they produce a dense, immersive fog effect. That said, this same
thickness can significantly reduce on-stage visibility, making them less ideal for occasions such as weddings where clear sightlines are essential.
When it comes to spray direction, fog and smoke machines generally fall into three categories: sideways, upward, and downward spraying models. Sideways-spraying units are the most common and affordable, with prices typically ranging from $20 to $38 each.
Upward-spraying machines tend to be more powerful and are better suited for large events such as concerts and theatrical productions. Downward-spraying models, often mounted on ceilings, are frequently used in nightclubs, bars, and karaoke venues. While refilling these ceiling-mounted machines can require more effort, the visual impact of 20 to 30 units releasing fog simultaneously is undeniably powerful—dramatically elevating the energy and ambiance of the space.
Dry ice machine
Dry ice machines are better suited for large-scale productions—such as theater, television, and theatrical performances—where a heavy, long-lasting ground-hugging effect is desired to quickly cover extensive stage areas.
Haze machine
Haze machines, on the other hand, are ideal for nightclubs and entertainment venues. They work particularly well with laser lighting effects. According to sales data from Grace Stage Lighting, they are also a popular choice among wedding planners due to their ability to enhance ambiance without obstructing views.
Consumables: Options and Costs
Fog, smoke, haze, and dry ice machines each require specific consumables: oil-based fog fluid, water-based fog fluid, haze fluid, and dry ice.
Among these, dry ice machines are considered the most eco-friendly. In contrast, oil-based fog fluids can sometimes interfere with the quality and output of stage lighting. It’s worth noting that some fog machines—particularly frost fog models—operate without a preheating period, they use water-based haze liquid.
In terms of cost, oil-based fog fluid is the most affordable, with prices starting as low as $3/bottle(In china). Dry ice, although non-toxic and better for the environment, tends to be more expensive. It also comes with practical challenges: storing and transporting dry ice for events can be difficult due to its temperature sensitivity and limited shelf life.
Safety Considerations
When using any of these effects machines, safety should always be a priority.
The fluids used in fog and smoke machines contain minimal chemical additives and are generally considered non-toxic. They are safe for inhalation and skin contact under normal use, though adequate ventilation is still recommended.
Dry ice machines produce a very low-temperature vapor that is completely odorless and non-toxic. However, direct contact with dry ice can cause frostbite, so handling requires caution.
In terms of consumable safety:
● Oil-based fog fluids may cause slight irritation in sensitive individuals.
● Water-based fluids are typically less irritating.
● Dry ice vapor is non-irritating and the safest option in that regard.