Precautions in Haz-Mat Photography

Precautions in Haz-Mat Photography

The growth of hazardous-materials response units throughout the country necessitates procedures that will make for safe but efficient operations. In most cases, prolonged exposure to the haz mat can’t be allowed. Most operating procedures require that a command post be out of visual range of the incident. This allows for only short close-up observations of the scene.

Recently, while filming a post-incident analysis of a haz-mat incident, I overheard an officer say that his unit had an instant camera (one that provides on-the-spot processing of film) to take to the scene for snapshots of labels, materials, and conditions, which could then be taken to the command post for reference. This struck me as an excellent idea—-valuable for safety and study. No long-term exposure would be needed to record data, and the pictures could be studied away from the site. But as 1 thought about this, several possible hazards occurred to me.

Think about what happens every’ time the shutter is released on most of the instant cameras on the market: electricity’ is released to the shutter and to the motor, pulling the picture through the rollers and discharging it from the camera. Since these cameras are not airtight, the spark produced in thq motor presents a hazard. These sparks last for as long as it takes to move the print out. Although the current is relatively low, even a small spark in an explosive atmosphere could have deadly results.

There’s a higher source of electricity within the unit: the capacitor that fires the strobe or flash. During a recent test on a relatively small strobe powered by 4 AA batteries, the discharge was 400 volts at 300 milliamps —a potential source of ignition. What happens is this: The capacitor acts as a kind of well, storing up volts generated by the batteries. Release of the shutter shorts out the capacitor, emitting electricity seeking the easiest path of resistance. Hopefully’, this path won’t lead it to an explosive haz mat. The batteries themselves aren’t imposing, but the power they’ give off to the capacitor builds up to levels that could be dangerous in the haz-mat situation. Compare this action to that of a garden hose filling up a 10,000-gallon tank. Getting hit by water from the hose is painless enough — but the force of 10,000 gallons of wafer is another matter.

Another cause for concern is the flash tube. The bulb is a vacuum tube. That’s not dangerous in and of itself unless it breaks, which would be unlikely. However, the tube is located inside a plastic housing that’s not airtight. When the tube is fired, the surface temperature becomes extremely hot for just a moment. Several attempts were made to measure the surface temperature of a flash tube, but the duration of the flash was too short. A simple test, just to get an idea of the amount of heat emitted, is to place your hand over the strobe and fire it. You may be very surprised.

The electronic strobe, flashcubes, bulbs, and flash bars are sources of heat for ignition. When dealing with materials that have low ignition points or wide explosive ranges, the simple camera flash could mean trouble.

Another potential risk associated with instant cameras is the way that the print is processed. Each print contains a chemical pouch. After the picture is taken, the print is pulled through rollers that squeeze the chemicals out of the pouch and apply them to the print. With most newer films, the chemicals are applied under a plastic cover, so that they’re not directly exposed to the touch. However, these covers aren’t guaranteed to be airtight. The film-processing chemicals which lay underneath them are basically alkalis. How might they react with a hazardous chemical? The user should be cautious. The odds of the film-processing chemicals coming into contact with the atmosphere are unlikely, but not altogether impossible.

During the post-incident analysis discussion, one of the haz-mat unit commanders remarked that they were using a video camera to record haz-mat incidents. The dangers in using video cameras are basically the same as those of instant cameras. Video cameras have motors that run the entire time the unit is in the record and pause modes. This is necessary to keep the heads spinning for instant recording, but increases the chances of sparking. Most video camera flood lights have an output rate of several hundred watts. There’s considerable heat output to go with it.

Although there are potential risks associated with instant cameras and video cameras, there are, nevertheless, ways to diminish them.

When the instant camera first came out, it had manual shutters, and prints were drawn out of the camera by hand. A meter (relying on an extremely low level of electricity) was used to set the exposure. With the exception of the meter, the camera operated by strictly mechanical means. As time went on, these simple cameras became cheaper, lighter, and easier to use. Film for these is still available. There’s one older-model instant camera on the market that is still pretty popular with some fire marshal offices. I have some of these older cameras and they still work fine—and they don’t produce electrical sparks.

There isn’t a whole lot that can be done about strobes. A faster film should be used to reduce the need for light, and a bright handlight could provide sufficient light for small areas.

If a video camera is chosen for recording haz-mat incidents, use a onepiece camcorder with an adaptable airtight underwater housing unit. These housings are available in dive shops.

The development of the CCD chip in video camera technology opened the door for faster recording speed and high-speed shutters. These new cameras have a low LUX rating (the amount of light necessary for the electronic, magnetic, and taping functions of the video camera to produce a highquality recording, measured in candlepower), which means better recording in low light. This may reduce the need for lighting altogether. If not, once again, a sealed handlight could provide enough light for filming. When considering a video camera purchase, remember that most sales are consumer-oriented. Be specific about the needs of your unit. Some video cameras have removable lenses which could be replaced by standard camera lenses. A high-power zoom lens or scope could be used when line-of-sight recording is possible. I believe the airtight housing is the best way to go.

If you choose to go with still photos, keep in mind that one-hour labs are numerous. This is not instant, but may fulfill your needs. The local lab may process film for the fire service before other customers during emergencies.

With line-of-sight shots, the variety of lenses and fast film is almost endless. There’s a portable processor on the market that allows for on-site development of slide film. The process takes 30 to 40 minutes. It’s 35mm film that’s compatible with any 35mm camera lens. Airtight housings can also be purchased for these cameras. If you have to use a flash, go with electronic. These have the most lighting power for the weight and can be placed inside airtight housings.

Simple, everyday tools and products can become potential dangers in the shadow of a haz-mat incident. Careful choice of the tools—including those used to record the incident —will be a great benefit to the safety and performance of your unit.

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