November 2, 2009 — Before firing up a laser on University of Virginia Grounds, talk to Stephen Adams.
He's U.Va.'s laser safety officer.
Based at U.Va.'s Office of Environmental Health and Safety, Adams is the safety consultant for the 120 research and 22 surgical lasers at the University and Medical Center.
A laser emits light electromagnetic radiation through a stimulated emission process. Lasers are used in research and have many applications in medicine.
They can also be used in cleaning. Adams, 27, was called in this summer when architectural conservators from Milner + Carr Conservation LLC of Philadelphia used lasers to clean accumulated grime from the capitals on Pavilion II.
"That was one of the most interesting applications," Adams said. "And there was a lot of interest in it."
There was interest because it was very public. While most laser use is conducted in a lab and has a limited audience, the conservators were working on the Lawn.
Adams' job was to keep the public and the workers safe. He erected barricades to keep the public at a safe distance. He also worked with conservators Leigh Hassler, a 2000 U.Va. Architecture graduate, and colleague Roy J. Ingraffia to make sure they were protected while using their small, hand-held lasers to clean the stone columns.
"We were using the laser right in the center of Grounds with hundreds of students passing by, so it was very important we follow all safety precautions," Hassler said. "Stephen came to meet with us before we started and was very thorough. The main concern is keeping people at a safe distance and that laser operators wear eye protection."
Hassler and Ingraffia used lasers to vaporize the soot on the Carrera marble ionic capitals without harming the stone and with no falling debris. The treatment restored the original bright white color of the capitals, which had been severely discolored through the years.
John Carr, a principal in Milner + Carr, said that without the lasers, chemicals or abrasives would have been used.
"Chemicals have runoff, which would have been deleterious to the columns underneath and the vegetation on the ground," he said.
Lasers have been used in industry for cleaning pipelines and sanitizing milk tanks, but have only recently moved into architectural conservation, Carr said.
Adams, who has a physics degree from U.Va. (and then went on to get a master's in statistics because he is fascinated with math), received training on national safety standards for lasers from the Laser Institute of America. As part of his work, Adams talks with students, researchers and medical practitioners who use lasers, as well as inspecting the areas where lasers are in use.
"I look at the big picture of the laboratory or operating room," he said. "The biggest hazard is a direct hit to the eye, or from a reflection. It's a matter of keeping people out of the way when the laser is operating."
He said eye exposure will not usually cause blindness, but may cause retinal damage and vision loss. There is also damager of burns on the skin, possible fumes or electrical problems.
Adams worries about patient safety as well. In the Medical Center, lasers are used in treatments such as eye surgery and plastic surgery, he said.
Laser use has expanded on Grounds, Adams said.
"There are five or six new laser labs," he said. "They are used a lot in research, in physics, chemistry and bio-chemistry. They are all over engineering and nanotechnology. The medical side has expanded, as lasers are used for more invasive surgery and new procedures."
"Vast leaps in technology" have reduced the size and increased the availability of lasers, he said.
"You can buy them on E-Bay," he said. "The Chinese make inexpensive lasers. Some are made for specific purposes, such as a laser welder that can cut steel."
Lasers should have stickers listing their maximum power, measured in Watts or Joules, he said, though they are usually operated below those peaks.
While Adams ensures safety guidelines are in place for powerful laboratory and medical lasers, he is not involved with less powerful laser pointers or similar applications. Heavy-duty laser safety isn't the only task Adams handles either. He also monitors fume hoods, indoor air quality, hearing loss issues and occupational noise.
In developing best practices for safety in all these undertakings, "I look at the worst-case scenario," Adams said. This method is working well. To date, there has been only been one laser accident in Adams' time at U.Va., with no serious injuries resulting.