Mitigate Mercury Spill Risks at Your Facility

Mercury-containing devices can be found in almost every setting imaginable: factories, hospitals, office buildings even homes. Staff and contractors who come onto your property or facility to perform services, are at risk 24 hours a days a week. Cleaning companies that offer their services on a contract basis are prime examples of a potentially at-risk group. Cleaning services often customize their schedule and work tasks to meet their clients’ needs.  Services can include vacuuming, mopping, dusting and cleaning windows.  Most cleaning is done after business hours or a specified shift.


Contract cleaning companies can provide their own cleaning equipment, which may be dedicated to a client’s site or the cleaning company may use their equipment on multiple sites.  Some companies mandate the cleaning company use in-house owned equipment only. Equipment use may also be a combination of the above.

Unforeseen Mishap

Rader Environmental recently responded to a mercury spill at a pediatric care center.  The spill was caused by a leaking mercury-containing sphygmomanometer (blood pressure cuff).  In fact, it was somewhat of a fluke that the spill was ever realized by the pediatric care center.

Two contract cleaning personnel that had cleaned the pediatric care center after business hours just happened to be talking the next morning about a blood pressure cuff that was mounted on wheels leaked some “silver stuff” on the floor while they where moving it to vacuum.  Their manager happened to overhear the conversation and realized that they were more than likely talking about mercury.

The manager of the cleaning company immediately contacted the pediatric care center and told them what may have happened the night before during their routine nightly cleaning.  The pediatric care center contacted the local health department, which arranged for the air inside of the facility to be tested for mercury vapor.

Mercury vapor was found to be at levels unsafe for occupancy.  The pediatric care center was forced to close for business until mercury was abated to safe levels for re-occupancy. Pregnant women and toddlers – the main clientele at this facility – are the most sensitive population to mercury vapor exposure.

Further assessment of the facility indicated that mercury had been spread throughout the facility by the vacuum cleaner.

The Double Whammy

The same vacuum cleaner that was used at the pediatric care center was then taken to another local business and used to vacuum carpet.  Mercury vapor readings indicated mercury levels too high for occupancy at this business, forcing the business to close its doors until mercury cleanup was completed.

Fortunately, these were the only two offices that were cleaned by the contaminated vacuum. By chance, the cleaning company’s manager happened to overhear the two employees talk about the silver substance they saw while vacuuming.

Both offices were abated and re-opened for business.

Food for Thought

  1. There is always a potential for a mercury spill if a mercury-containing device is on your site.
  2. Dedicated cleaning equipment can eliminate the risk of contaminated equipment entering or leaving your business.
  3. Train all personnel (your employees and contract personnel) to recognize mercury and what to do in case of a mercury spill.
  4. Replace mercury-containing devices with non-mercury containing devices whenever possible.
  5. If you must utilize mercury-containing devices, train all personnel what to do in case of a mercury spill and the hazards of mercury.

The mercury spill in the pediatrics care center could have easily been overlooked exposing staff and patients to mercury levels that are hazardous to one’s health for an unknown amount of time.

Mercury Remediation

Rader has performed numerous mercury remediation projects ranging in size from thermometer spills to soil remediation in large industrial settings. The following is an example of a project Rader completed that required a diverse remediation plan.

Rader completed a major mercury abatement project for the Texas A&M University system on one of their Texas campuses. This was a 46,000 ft² science building constructed in the early 1960′s. It was used for research and teaching and became contaminated with mercury throughout the entire building.

Based significantly on our previous mercury abatement experiences, Rader was selected for a pilot program designed to develop procedures for abating the entire building. We worked closely with Texas A&M’s representatives and an oversight engineering firm. Based on our performance, the value we brought to the project and overall schedule requirements we also were awarded the subsequent contract for cleaning the entire building. Texas A&M realized a project savings of approximately 45% of the remediation budget.

Non budgeted saving were also realized by Texas A&M. Rader’s experience and knowledge was utilized to abate fixed furnishings, shelving, furniture, expensive laboratory equipment and valued documents.

Through the planning stages of the project, Texas A&M referenced a review by the National Academy of Sciences (NAS). The review supported the EPA’s Reference Dose (RfD) but used different cohorts (Pacific Islanders), effects (mild memory loss) and a 30x factor (for uncertainties). The Boston Naming Test was used to measure changes in recognition / recall (nominal dysphasia). In support of the review, Texas A&M adopted this 30x factor, and set the clean up criteria as an average of 1.3 ug/m ³ and an action level of 3.0 ug/m ³.

At the end of the abatement process clearance sampling was performed. Temperatures were elevated in the building to 95 ° F. Blowers were used to simulate normal building activity during the sampling process. Over 30 NIOSH sample points were placed on each floor. The Lumex was also used for “snapshots” during the sampling process. The final clearance sample results are as follows:

  NIOSH 6009 Lumex
Basement Not Available 0.68
ug/m ³
First Floor 0.81
ug/m ³
ug/m ³
Second Floor 0.65
ug/m ³
ug/m ³
Third Floor 0.86
ug/m ³
ug/m ³
Fourth Floor Not Available 0.12
ug/m ³

Included in the final results is a notable similarity between NIOSH sampling and Lumex field screening analysis.