It's the kind of situation that develops more frequently than lead control professionals would like to see: Possible lead contamination in a building. In this case, it was a private day-care center connected to a private elementary school in the Midwest. The center served 98 students, from infants to pre-kindergarten. The potential lead exposure to the children was the end result of a chain of events similar to many exposure incidents. The day-care center is housed in a former high school. Initially constructed in 1930, its approximate 30,000 square feet is separated into two floors. The second floor gym and six classrooms on the first floor had hardwood floors serviced by a radiator steam heat system. Funds had been raised to renovate the building and an ambitious plan was in place to replace all of the large exterior windows, complete needed repairs on the boiler and piping systems, renovate the bathrooms with new fixtures and tile and repair damaged walls, and repaint the entire interior of the brick structure.

Troubles begin

Troubles began when windows arrived for installation two months earlier than anticipated. Neither the day-care center nor the contractor had any place to store the massive units. A mild winter rolled into an early spring so the authorities decided to begin the renovation project before school got out for the summer rather than during it, as was originally planned. Although the state, OSHA and EPA regulations require the contractor to be aware of lead hazards in construction activities, the state did not require any lead inspections of daycare centers or elementary schools prior to construction activities. Ironically, at the time of this incident, legislation was pending before both the state house and senate which would have required training and certification for lead and the use of licensed contractors for any remediation activities.

Discovering contamination

Construction began at the day-care center the week before spring break. Work on window replacement was to begin on the upper floors and move down. Wooden frame windows were removed from the building by pulling the exterior trim and pulling the windows out as complete units. The work generated some debris and paint chips inside which were not contained by a drop cloth or other engineering controls by the window contractor. During the week of spring break, all the second floor windows and some of the first floor classroom windows were replaced. When the students returned from their break, some staff members raised concerns about the possibility of lead in the wall paint or contamination of the building and hazard to the children. Unfortunately, the administrator responsible for responding to such concerns was on vacation at the time so no immediate corrective action was undertaken.

Conducting tests

One Thursday afternoon, representatives from the County Health Department and local news media showed up at the day-care center. They introduced themselves to the staff and accepted an invitation by one of the care providers to enter the building to begin sampling. Initial XRF (X-ray fluorescence) results revealed lead in both the wall paint and construction debris. Then the health department officials and the reporter opened the stairwell door to the second floor gym and found a painting contractor scraping and sanding portions of the wall. A thick cloud of dust was hanging in the air. They asked the painter to stop work. The investigators found the gymnasium floor covered with dust and initial examination with the XRF instrument indicated that the dust contained lead.

After the initial assessment, the inspector collected a number of wipe samples to confirm his assessment of lead contamination throughout the facility. When the lab reports were received the next day, the County Health Department issued a 'cease and desist' order. At this point, the facility operator contacted Wonder Makers Environmental, a general industrial hygiene consulting firm that specializes in asbestos, lead and indoor air quality to assist them in investigating and developing appropriate remediation efforts.

Taking control

After an initial visual inspection of the facility and collecting wipe samples, the environmental specialist from Wonder Makers Environmental compared a color change on the LeadCheck Swabs to the EPA recommended action level of 100 micrograms per square foot on a flat surface. By using this technique, known as the Pinto Protocol,( for additional information on the Pinto Protocol, contact the author) the specialist showed the building authorities a number of areas with contamination at levels above the HUD ( Housing and Urban Development) guidelines.

While waiting for lab reports, the contractor installed the remaining windows so the cleaning efforts would not be jeopardized by subsequent construction activities. The decision to allow the contractor to move forward with installing additional windows was based primarily on the LeadCheck Swab sampling which indicated that most of the lead dust contamination was the result of the sanding and wall preparation that went on in the upper floor, not the disturbance that was created by the replacement of the windows. This was later confirmed by both the County Health Department and Wonder Makers Environmental. It was further supported by the fact that the window trim was varnished hardwood, which tested negative for lead using both the lead check swabs and the county Health Department's XRF instruments. A test was conducted for the third time and the LeadCheck Swabs and XRF showed that the lead was found over layers of paint which were now covered by non-leaded materials.

Lab sample results: A hypothesis is developed

Lead contamination levels range from 53 micrograms per square foot to 10,000 micrograms per square foot. These concentrations were found on the gymnasium and stairwell where a surface preparation for painting had taken place. The classroom areas on the first floor had proven to have much lower levels of lead than the dust.

A couple of days later, the building's administrators met with the representatives of the County Health Department and Wonder Makers consultants to develop a comprehensive plan to clean and test the building. The plan incorporated the use of a trained hazardous materials contractor to clean the interior of the building thoroughly. The LeadCheck Swabs used in components with the Pinto Protocol would be used throughout the cleaning process to give feedback to the crew regarding the effectiveness of the efforts (i.e., an area 3/8th of an inch wide by 14.39 inches long would be wiped with an activated LeadCheck Swab using a template to keep the tip from mushrooming. If this wipe produced a discoloration to pink within one hour, it would be considered as evidence of contamination above 100 micrograms per square foot). The Pinto Protocol was also to be used prior to final clearance sampling as a last check to identify the effectiveness of the cleaning.

Along with cleanup of the day-care center, Wonder Makers Environmental set up an investigation of the nearby elementary school in order to allay any concern that the contamination may have spread. Once again, LeadCheck Swabs were used to provide immediate feedback and correlate 100 percent with the subsequent lead sample results. Everyone involved in the project was relieved when first the LeadCheck Swabs and then the wipe samples showed no contamination above the 100 micrograms per square foot.

The day-care center was the primary focus of the cleanup efforts. A detailed work plan required cleaning from the floors up to the ceilings in all areas of the building. HEPA (High Efficiency Particulate Air) vacuums and wet wipes/mops using a commercial deleading cleaner were the primary cleaning procedures used in the building. LeadCheck Swabs, a key component of the entire cleaning process, confirmed the effectiveness of the cleaning. In one case, the chemical spot test was used eight times before the floor in one area of the building was clean enough to pass a final clearance sample test. In that particular case, the chemical spot test was useful not only from a qualitative standpoint but from a semi-quantitative state as well. The reaction time and state of the color evidence by the swab were both used as indicators to show the crew that efforts were bearing positive results, but were not leaving the floor surface clean enough to move on to the next area.

Moving forward

In the case of emergency response to potential lead contamination, providing timely and credible information is important for proper management of the situation. The wipe samples analyzed by a certified lab are an important factor in protecting the health of building occupants in such situations. The use of chemical spot tests to assist with the initial assessment of the site, to gauge the effectiveness of ongoing cleanup, and to reduce the possibility of lost time through failed clearance samples, is an important 'fix advancement.'

Using such technology will assist the lead control professionals in making decisions that are data-driven rather than based strictly on professional judgments and past experience. This improved decision-making can help eliminate the fear and confusion which inevitably accompanies such emergency situations.

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