Tech Challenge Testing Lab Cleanliness CelTek Labs works with many different bacteria, all pretty harmless and naturally occurring. Many of the employees have expressed concern about sanitary conditions and the effectiveness of cleaning techniques on various surfaces. What product would you suggest they use to test cleanliness of their environment? A: Glo-Germ Portable Sanitation Training Kit contains oil and plastic “germs” that glow under UV light to help show spots and indicate how effective hand-washing is. It includes a battery-operated UV flashlight to make the “germs” glow. B: Microbial Air Samplers, which are cost-effective samplers for monitoring airborne bacteria, viruses, molds, and fungi. C: Prepared Media Plates, which are nonselective media that grow just about any mold or bacteria the agar is exposed to. D: VERIcleen Rapid Surface Hygiene Indicator Kit includes 60 strips and a spray bottle to wet surfaces for testing.. E: Ultraviolet Light working at 265 and 365 nm wavelengths. Answers: A: Glo-Germ portable sanitation training kit contains oil and plastic “germs” that glow under UV light to help show spots and indicate how effective hand-washing is. It includes a battery-operated UV flashlight to make the “germs” glow.
Incorrect. Perhaps more applicable to the food service industry in which employees wear gloves while dealing with the colonies. Showing the employees the effectiveness of their hand-washing may not be as appropriate. B: Microbial Air Samplers, which are cost-effective samplers for monitoring airborne bacteria, viruses, molds, and fungi.
Incorrect. This is more applicable to the food and drug industries who are concerned with airborne contaminants and toxins or hazards. C: Prepared Media Plates, which are nonselective media that grow just about any mold or bacteria the agar is exposed to.
Correct. These media plates will need incubation (available in any microbiological lab), but will allow employees to test specific areas and surfaces. They also let users compare the results to other places or spaces to get an idea of “blank” or “control” values (considering naturally occurring microbes are being handled). To compare lab versus external surfaces, a total colony count could be used. D: VERIcleen Rapid Surface Hygiene Indicator Kit includes 60 strips and a spray bottle to wet surfaces for testing.
Incorrect. These test strips are activated by food residues such as those in meat, diary, eggs, fish, etc. This product is more applicable to the food service industry. E: Ultraviolet Light working at 265 and 365 nm wavelengths
Incorrect. This would assume that the bacteria fluoresce at the given wavelengths. The 265 nm light, if held over the surface long enough, could actually assist in cleaning. It is often used in the sterilization of bacteria, mold, and viruses in many industries, including water, labs, dog kennels, and more. Determining Flow Rate at Various Points on a Golf Course A groundskeeper at a large golf course needs to measure the flow rate in the watering system at more than 30 different points throughout the course. With several miles of pipe, the diameters vary from 2 to 4 inches. The groundskeeper also indicated they want to monitor the flow continuously for 10 minutes at each point of measurement. They have a budget of less than $10,000. Which flowmeter and process would be ideal for this application? A: Install spring-loaded flowmeters at each point around the course. Take readings every 15 seconds and record them in a notebook. B: Install tee-fittings with paddle wheel sensors at each monitor point and carry a battery-powered meter around the course. Take readings every 15 seconds and record in a notebook. C: Use a Handheld Doppler Flowmeter and take readings every 15 seconds and record them in a notebook. D: Use a Portable Transit-Time Flowmeter and program the data logger’s sample rate for one reading per second. Answers: A: Install spring-loaded flowmeters at each point around the course. Take readings every 15 seconds and record them in a notebook.
Incorrect. This system would not be ideal because of the significant water flow downtime to install more than 30 fittings throughout a large golf course. In addition, the readings are somewhat far apart because of the time it takes to physically record data points, which is not really close to continuous monitoring. Finally, there would be flow restriction in the larger pipes due to the size of the flowmeter. B. Install tee-fittings with paddle wheel sensors at each monitor point and carry a battery-powered meter around the course. Take readings every 15 seconds and record in a notebook.
Incorrect. Although this setup would work, it is cost-prohibitive to buy 30+ sensors. Also, the same issues exist with downtime for installation and noncontinuous readings as with the spring-loaded flowmeters.. C. Use a Handheld Doppler Flowmeter and take readings every 15 seconds and record them in a notebook.
Incorrect. The water will be too clean for this type of technology, which requires particulates or bubbles to work properly. This unit does not have data logging capability either. D: Use a Portable Transit-Time Flowmeter and program the data logger’s sample rate for one reading per second.
Correct. This type of flowmeter can measure clean water, has a programmable data logger, and can be moved from pipe to pipe easily, so only one unit would be needed. This would keep the groundskeeper under budget.
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