American Research and Testing Inc.: Case Studies
American Research and Testing Inc. specializes in industrial forensics -- that is, investigative chemical analysis and chemical problem solving. If you have a product defect or failure that is related to chemical composition or chemical contaminants, we can perform a good vs. bad analysis to determine the cause of the failure or defect. Here are some short descriptions of interesting problems we have solved..
Characterization of Floor Effluent
- The problem: A building for medical device manufacturing was in the process of being built, over a remediated site. The new epoxy/aggregate floor coating of the building had many areas on it where a stream of yellow liquid would propell out of it when passers-by walked on it.
- Our client: The architectural/construction firm that was building the site
- The questions: What is the yellow liquid, does it come from incomplete remediation, and is the epoxy/aggregate floor coating defective?
- Description: The yellow liquid consisted of highly alkaline water, calcium carbonate, epoxy, and an ethylene glycol derivative. None of these components was part of the remediation target compounds. Further investigation revealed that parts of the remediated area were open pits which had been filled with a cementitious slurry. These slurry areas corresponded with the locations of the epoxy/aggregate floor which had deteriorated. Core sampling showed that there was a considerable amount of standing water beneath the construction site. Water that leached through the slurry was highly alkaline, but water that leached through only the concrete slab was not alkaline. The alkaline water had hydrolyzed the free epoxide in the epoxy floor, resulting in the ethylene glycol derivative. Bench-scale experiments and a literature search showed that this decomposition was a normal characteristic of the epoxy product. Further investigation revealed that the epoxy aggregate was not marketed as a water-resistant product, and was not guaranteed to withstand moisture conditions. In fact, the installation literature recommended that the epoxy product be applied only to slabs that had been installed over a water-proof membrane. Inspection of the architectural plans showed that no water-proof membrane had been specified by the building designers.
- Conclusion: The alkaline conditions of the water that had wicked up through the slurry caused the epoxy flooring to degrade. This was a design and specification defect, rather than a materials defect or incomplete remediation.
- Outcome: The floor and concrete slab had to be removed, and replaced over a water-proof membrane.
- The problem: A two-component epoxy paint system had been applied to the interior concrete walls of a dairy processing plant, where typical humidities were quite high. Within weeks, the paint began to yellow and blister, and the dairy refused to pay the painter until it was fixed. The painter refused to pay the paint company, asserting that the paint was defective. Cross-complaints ensued.
- Our client: The law firm representing the dairy processing plant
- The question: Why did the paint fail?
- Description: Most epoxy systems contain two components: a) the epoxy, and b) the curing agent. In order for the system to cure properly (and achieve the desired physical properties such as adhesion and chemical resistance) the epoxy and curing agent must be mixed in specific proportions. Empirical physical tests showed that subtle misproportioning of the coating system greatly affected its resistance to high humidity. That is, misproportioned coating applied to concrete and cured under highly humid conditions blistered and turned yellow. The same conditions did not cause a properly proportioned coating to blister and discolor.
- Conclusion: The cause of the problem was in the use and application of the product. The product was not defective.
- Outcome: The dairy and the coating company withdrew their lawsuits against each other after deposition. The coating company hired us to be their expert, and the case was settled out of court.
- The problem: An adhesive used to install countertop laminates was believed to be defective -- either inappropriate for the intended use or mis-formulated, based on a laboratory's identification of the adhesive. The family of the deceased countertop installer was suing the adhesive manufacturer for damages, asserting that the defective adhesive was the cause of the delamination of the countertops, the failure of the business, and ultimately the stress that caused the demise of the installer.
- Our Client: the law firm representing the adhesive manufacturer
- The questions: Was the adhesive chemically defective? That is, were there any components missing from or added to the lot in question? What was the cause of delamination?
- Description: A laboratory batch of adhesive was prepared from the manufacturer's recipe and raw materials. The resulting adhesive was chemically characterized, and compared to the dis-bonded adhesive on the countertop. No chemical differences were found. Close inspection of the delaminated countertop in comparison with the application directions showed that not enough adhesive had been used in the installation. Further investigation showed that the plaintiff's laboratory had mis-identified the adhesive as an acrylate (it was a styrene-butadiene adhesive) and had made some conclusions regarding its appropriate use based on the mis-identification. During the discovery process, it was learned that a previous lab the plaintiffs originally had gone to had also determined that there was not enough adhesive on the disbonded countertops, and that there was no discernible chemical difference between the exemplar and disbonded adhesive.
- Conclusions: The second testing laboratory made a mistake, giving the plaintiffs erroneous information upon which they based their lawsuit.
- The outcome: This case was settled out of court a day before jury trial began.
- The problem: A white-colored haze had appeared on the surface of the plastic component to an automotive interior.
- Our client: The OEM component producer
- The question: What is the surface contaminant?
- Description: This is actually a question that has been asked many times by many manufacturers of plastics. Sometimes the contaminant is the mold release agent. In a particular case, the molders were unknowingly (and intermittently) using a grade of plastic that had glycerol monostearate added to it for use as an internal lubricant. In another case, the contaminant was aluminum oxide powder which had deposited on the wet paint of the plastic. In many cases, where a paint is involved, the solvents in the paint leach out the stabilizers in the plastic, leaving a residue on the surface when the paint dries.
- The outcome: Identifying the contaminant helps identify the cause of contamination. Once the cause is identified, precautions and procedures can be put into place to prevent a reoccurrence.
Adhesive Bond Failure and Characterization of a Malodorous Ooze
- The problem: The granite pavers at a commercial building plaza had disbonded shortly after construction. Epoxy adhesive was injected under the granite pavers in an attempt to rebond with the cement setting bed. Within weeks, many of the pavers had disbonded again, a sticky substance was oozing up between the paver joints, and a strong odor permeated the plaza.
- Our client: The law firm representing the plaintiff property owner
- The questions: What is the ooze, what is the odor, and what is the probable cause of the failed rebonding attempt?
- Description:Most epoxy systems contain two components: a) the epoxy, and b) the curing agent. In order for the system to cure properly (and achieve the desired physical properties such as hardness and adhesion) the epoxy and curing agent must be mixed in specific proportions. Laboratory tests showed that the sticky ooze was misproportioned epoxy -- the curing agent and epoxy proportions had been swapped. The odor permeating the plaza was that of the over-abundant curing agent. Since the plaza re-bonding project had been performed over a period of several weeks, some of the epoxy had been proportioned properly and had fully cured, yet the pavers still disbonded from the setting bed. Close inspection and chemical analysis showed that two conditions existed under the pavers prior to epoxy injection: there had been standing water, and there was particulate debris. Both of these conditions precluded good adhesion of the epoxy to the setting bed. Manufacturer's instructions for use of this particular epoxy system required debris-free bonding surfaces, and no standing water. Since neither of those conditions could be achieved, this was not an appropriate way to use the product.
- The outcome: This lawsuit was settled out of court in favor of the plaintiff, minutes before jury trial was to begin.
CO Permeability of Tent Fabric
- The problem: A man and his son went camping, and used a charcoal barbeque inside their tent to keep warm during the night. The next morning, the son woke up to find his father dead of carbon monoxide poisoning.
- Our Client: The law firm representing the plaintiff family of the deceased
- The questions: How high does the carbon monoxide level get in a tent from a smoldering charcoal barbeque, how quickly does the level become lethal, and how does the fabric weave of the tent affect these levels?
- Most people have been warned all their lives not to use charcoal in enclosed spaces due to dangerous carbon monoxide levels. Nevertheless, the family of the deceased felt that the tent fabric could have been more breathable, and asserted that the tent manufacturer had indeed discontinued using the fabric of the tent model in question because it was not breathable enough and was therefore liable for the death. The replacement tent model had a different type of fabric.
- Air flow tests showed that the replacement model fabric indeed was more breathable than the fabric of the model in question. A series of monitoring tests were conducted on the carbon monoxide levels generated by a smoldering barbeque inside both models of tent. These tests showed that the carbon monoxide level inside the tent of the questioned fabric was 1000 ppm within 10 minutes, and maintained at least that level for an hour. Inside the tent of the new fabric design, the carbon monoxide level never exceeded 400 ppm. Toxicology literature stated that 1000 ppm of CO for an hour was lethal to some people, whereas 400 ppm of CO for an hour was not.
- The outcome: Although these tests proved that taking smoldering charcoal inside a tent was dangerous and could be fatal depending on the permeability of the tent, the plaintiff's assertion that the tent manufacturer was liable for the death due to design defect was turned down by jury trial.