Film-Tech Forum ARCHIVE: Static Electricity in Booths

This is topic Static Electricity in Booths in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Gary Crawford (Member # 2038) on 03-23-2004, 01:33 PM:

In old booths static electricity is a problem during dry winter months. Our old theater doesn't have exotic new HVAC systems with humidity control. Sometimes the static is terrible. You can't touch anything without getting zapped.

A quick fix we used in a TV control room was when someone bought metal fondue skewers at a yard sale. Keep one in your hand and touch metal with that instead of you finger! Silly, but it works. A screwdriver will too.

A cheap fix can be simply a box of those sheets you use in the dryer. They somehow absorb static in the air (just like they do for clothing in the dryer) and smell nice too. Hang a couple around the booth. Looks dumb but it works.

Someone told me to place a pan of water on the radiator (told you we had an old heating system) but I'm not thrilled about an open pan of water around that equipment. A spill could be a disaster, especially with a big Christie K30 lamphouse within 30" of the radiator.

There isn't much room for a humidifier in there, even a small floor model.

Without resorting to expensive HVAC upgrades, anyone have anti-static tips for old booths?

Posted by Bill Enos (Member # 440) on 03-23-2004, 09:45 PM:

Put two or three ounces of liquid fabric softener in a quart of water and very lightly mist the floor, even if it's tile on the way out for the night. It will be dry in an hour, but whatever is in the stuff will be left and eliminates static.

Posted by Chris Medley (Member # 2145) on 03-24-2004, 01:38 AM:

I would suggest using a grounding strap when your building if you run a platter house because even with humdity controls I've had a few shocks. Also, before we installed our nice new HVAC systems we had lots of static...the main thing is to keep a clean booth or you will be fixing brainwraps all day (again if you are in a platter house). We tried the laundry sheets with little effect. I would go for one or two humidty monitors from your local radio shack or home depot and the if you do use a humidfier, don't get one that uses a water mist and you should be fine. You may try shutting off the booth units alltogther...yeah it will be cold, but with a couple of machines going you will be fine.

Posted by Jason Thode (Member # 1854) on 03-24-2004, 04:35 PM:

During the winter when static starts to affect us and the film, I would have my projectionists fill pickle buckets full of hot water and place them under our strong platters. The steam rising from the hot water would raise the humidity and placing them under the platters wasnt a danger because you couldnt knock them over without knocking over the platter system. It did the trick and kept the prints from static wrapping. [thumbsup]

Posted by John Pytlak (Member # 331) on 03-29-2004, 03:40 PM:

Evaporative humidification is the lowest cost and most effective method of increasing relative humidity in film-handling areas, hopefully to the recommended range of 50 to 60 percent RH.

Portable "console" type evaporative humidifiers blow air though a foam or paper wick soaked with water. Some units can put up to 10 gallons (about 40 liters) of water per day into the air.

Here are just a few:

http://www.shopping.com/xPP-Humidifiers--bemis

http://www.shopping.com/xPP-Humidifiers--bionaire

http://www.shopping.com/xPP-Humidifiers--aprilaire

Vaporizers ("cold mist" or ultrasonic units) that mist or spray water into the air are NOT recommended, as the minerals in the water will be deposited on equipment, and "raw" moisture could cause corrosion or rusting of equipment, or electrical problems. Steam vaporizers are very expensive to run, as use lots of electricity to boil the water. Putting pails of water around the booth is ineffective, as the evaporation rate from such a small surface area is minimal.

Non-conductive surfaces like carpets, fabrics or plastic surfaces can be treated with a conductive anti-stat like Static Guard, Staticide, or Neutrostat. Even anti-static fabric softener can be used. Electrically ground all film handling equipment, and treat non-conductive rollers with an anti-stat to provide a path to ground from the film.

Always use approved grounding methods (like a conductive wrist band connected to ground) to avoid charge buildups that can cause surprising shocks or damage sensitive circuit boards.