CONTRACTOR INGENUITY

Ideas

That Work,

Portable Isolation Enclosure

Reported by David Bolton for Jerry Strieter

Reprinted with permission of Outlook, March, 1989

The job description was demanding. The contractors learned that the company expected the abatement to be completed at night and on weekends, so its federal tenant, the General Services Administration (GSA), would experience no work cessation. Clearing the air for analysis would be the biggest challenge; arriving at the final air readings could take twice as much time as the removal itself.

Enter Jerry Strieter, President of Southern Insulation, Inc., a Hyattsville, Maryland, firm specializing in asbestos abatement. Strieter submitted two bids: one for total enclosure and another that employed a portable isolation enclosure-at one-third the cost of containment. Strieter was confident that this type of enclosure unit (which he invented thanks to his ingenuity) would work. Intrigued, the company contacted Strieter and asked him to test his invention, Strieter put together the portable isolation enclosure, a cubicle with an extendible shroud that fit on top. A HEPA filtration system drew air down from the ceiling. Inside the enclosure was a suited man; opposite was a trapped door with a bag attached. Strieter's idea was for the worker to remove the tile, clean off the grid, and deposit everything in the bag after opening the trap door. Suction would pull the trap door shut. Within the enclosure was a shower attachment, used for washing the closed bag and self-cleaning.

This asbestos abatement contractor did some initial analysis in-house with an industrial hygienist, who is an expert on airflows. Then in a vacant space in one of the company's buildings, Strieter perfected his method. Searching for the ideal CFM (cubic feet per minute) available through air filtration units, Strieter experimented with different airflows, using smoke tests to see if there was enough of a draw. Said Strieter: "Once we had the unit against the ceiling, we got good suction. The difficulty came when we started opening up ceiling tiles or a plaster ceiling to create bigger space. We were suddenly bringing in a lot more volume of air."

By measuring the pressure differential inside and outside the enclosure, Strieter determined he needed a larger air-moving machine, capable of moving 1800 to 2000 CFM to ensure that dust would not go backwards, and that contaminated debris would not penetrate the exterior because of any additional air movement in the enclosure.

Strieter's idea was a rousing success. Southern Insulation performed the abatement without disturbing the tenants. After completion of the project, the company contracted Southern Insulation for additional work. Since 1987, Southern Insulation has abated over 300,000 square feet of ceiling tile for the companies.

It would be only the beginning of the applications of this enclosure invention. Southern Insulation used its invention at the EPA headquarters in Washington, D.C., for spot removal on a plaster ceiling coated with asbestos. "Over the years the ceiling had become friable," said Strieter. "The problem was that the ceiling was 23 feet high. We had to set the units on top of scaffolding. Using the enclosures, we scraped off and patched up a couple of thousand spots-by far the quickest and safest way to do it. People came in Monday morning and said the place was cleaner than before. With five units working, we completed the job in two weekends."

At the Pentagon the portable isolation enclosure cut in half the time required to cut access doors in their plaster ceilings containing asbestos. Added Strieter: "We tried using a glove bag method with a duct jack. A crazy type of arrangement that worked, but it was slow. We got twice the production out of the enclosure, what we call the 'mousetrap'."

One of the advantages of the 'mousetrap' is its capacity to be moved with ease from location to location. The shroud, extendible up to 12 feet, can be removed. It weighs from 40 to 60 pounds (the heavier shroud extends out from the enclosure so it can be used over desks, file cabinets, etc.). Made mostly of aluminum, the enclosure itself, along with a negative air machine and HEPA filtration unit, weighs less than 200 pounds and rolls without difficulty through doorways.

The mousetrap's portability makes it ideal for maintenance. For example, a ceiling could be contaminated from above. If in the contaminated area there's a leak or a valve that requires adjustment, the maintenance person could "pop" the ceiling from within the enclosure without fear of endangering his own health or dropping the debris on the floor. "The only other safe alternative would be to seal off the entire room," said Strieter. "This alone would take half a day. With the mousetrap, we can roll the thing in and be ready to go in five minutes."

Armed with a patent, Strieter has begun to market his invention nationwide through distributors. Schools have expressed interest because of the advantages it offers with maintenance.

Strieter recently received a call from a manufacturer in England, who said he had made something similar, but it was not nearly as effective. This British businessman expressed an interest in purchasing the rights so he could manufacture the mousetrap and distribute it in Europe.

For many contractors, asbestos abatement has been a "grow-as-you-learn" industry. Evolving regulations have challenged contractors to be inventive on the job, to come up with new abatement procedures, which are not only safe but also cost-and-time-effective. Jerry Strieter's invention of the portable isolation enclosure reflects this creative process. Such new ideas help raise the competency of the entire industry.

SOUTHERN CONCEPTS, INC.

5218 Monroe Place

Hyattsville, MD 20781