Theatrical smoke and fog

}} Theatrical smoke and fog, also known as special effect smoke or haze, is used in the entertainment industry in motion picture and television productions, live theatre, concerts, at nightclubs, raves and even in some video arcades. They are used for creating special effects and to make lighting visible. When you are at any of these entertainment venues and you can see beams of light, that means smoke and fog are being used otherwise the light beams would not be visible.

These smokes and fogs are created by heating different glycol mixtures until they start creating a mist via the use of a fog machine. Another method is by atomizing mineral oil via a machine that works much like a spray pump breaking the oil into a fine mist. While it is commonly believed that these fogs are created by dry ice or liquid nitrogen, this is rarely what smoke and fog are made of. Dry ice and liquid nitrogen create a fog that only lies low to the ground and isn't so useful at concerts, live theatre or television or film production for this reason. Even the army uses smoke and fog to mask troop movements on the field.

Adverse Health Effects

Four studies{cite} have been published on health effects from exposure to theatrical smokes and fogs. Two of the studies focused on the effects on actors and performers on Broadway musicals and a remaining study looked at the use of fog in the commercial aviation industry for emergency training of staff to stimulate fire conditions. The most recent study, published in the American Journal of Industrial Medicine in May 2005, looked at adverse respiratory effects in crew members on a wide variety of sights ranging from live theatre, concert, television and film production and in a video arcade.

Exposure to smoke and fog was related to upper airway and voice symptoms. Additionally, shortterm exposure to glycol fog was associated with irritated mucous membrane symptoms such as dry throat/dry cough and irritated eye symptoms. Shortterm exposure to glycol fog was also associated with headaches, dizziness, drowsiness and tiredness. It is unlikely that these findings regarding glycol fog are psychosomatic as the exposed populations would not have been aware that they were exposed to glycol or mineral oil fogs at the time. Exposure to smoke and fog can cause both short-term and long-term respiratory health problems.

Ways to reduce exposure to Theatrical Smoke and Fog

On sets, the number of crew members should be limited to the smallest number necessary when using fog. Additionally, scenes requiring fog should be scheduled towards the end of the workday to allow the room to clear out without employees in the environment. Steam-based fogs or camera filters would be ideal compared with using glycol or mineral-oil based fogs. Warnings should be placed for those with preexisting respiratory conditions such as asthma that fog is being used in a certain venue such as live theatre. The use of digital effects in post production on film and television sets is a safer practise than using theatrical smoke and fog during filming.