Laboratory Ventilation Challenge: Carlos was interested in a ductless fume hood. He had moved into a new lab that already had proper rooftop ventilation and ductwork suited for a ducted fume hood, but had heard a lot of good things about the mobility of the ductless type. Carlos was going to be using a wide range of chemicals under this hood. His only concern was the dimensions of the ductless hood—would it easily move around all part of his lab?
Carlos needs a little help in making a decision. A) A ductless hood that matches his dimensional requirements should be fine. B) Both types of hoods work the same, so either would be acceptable. C) A ductless hood consumes more energy per year than a ducted fume hood, so ducted would definitely be the most economical choice. D) He should forget about the ductless fume hood and stick with the ducted since the ductwork is already in place. Answer: A) Incorrect. There is definitely more to a fume hood that just the dimensions and mobility. More detailed information regarding the chemicals being used would be needed before making a decision. B) Incorrect. The two types of hoods ideally have the same function but are actually quite different in the way they operate. More detailed information regarding the chemicals being used would be needed before making a decision. C. Incorrect. A ducted fume hood consumes more energy per year than an average house; more than a ductless. D. Correct. This is Carlos’ best option as he will be working with many different chemicals and a ductless fume enclosure is limited to certain chemicals. Not to mention that the ductwork is already in place for a ducted fume hood. Although the ducted type consumes more energy, it would better suit his needs. _______________________________________________________________________________
Chemical Testing Challenge: The U.S. EPA was testing rivers and lakes for chemical levels. The technician detected above-regulation levels in Lake Somhe, including phenol, toluene, mercury, oils, and more. There are a dozen different factories and pipelines which empty into Lake Somhe, and the EPA needs to determine which of these sources is contributing to the unacceptable chemical levels before doing a more in-depth analysis at the individual site. The EPA contacted Cole-Parmer to find instruments or tests that can help them quickly and easily determine which sites are causing the problem.
Which test would be most effective for their purpose?
A.) Recommend a chemical classifier which work similar to a pH paper strip. B.) Suggest the technician start with a colorimeter to determine phenol and toluene levels. C) Suggest a gas chromatograph and mass spectrophotometer to determine phenol and toluene levels. D) Have the EPA collect samples from each site and send to an independent testing laboratory. Answer:
A.) Correct. The EPA only needs to find out which sources are dumping the chemical waste; they do not need to know the actual quantitative amounts. The chemical classifier strips are sufficient for quickly determining if the chemicals were at a certain limit at a specific site. Plus, the strips are economical and easy to use—simply wet them and compare them against the color indicator chart. B.) Incorrect. The colorimeter provides an actual measurement and is costly. At this point the EPA does not need detailed results; they only want to determine which of the individual sites has any trace of the offending chemicals. C) Incorrect. For a preliminary test it is not logical to purchase expensive capital equipment. The EPA first wants to quickly determine which of the individual sites has any trace of the offending chemicals. D) Incorrect. Sending multiples samples to an independent testing facility would be very costly and have a long lead time. _______________________________________________________________________________
Circuit Board Failures Challenge: A manufacturer of electrical test equipment noticed that circuit board failures increased during the fall and winter, and decreased during the spring and summer months. After a thorough investigation of the failures, it was determined that certain individual components on the circuit boards were damaged internally.
Which of the following actions should be taken:
A) Install a cleanroom and implement cleanroom procedures B) Increase the number of inspections of individual components before installing them on the circuit boards. C) Rotate component stock to see if older stock is the source of the failures. D) Add a surge protector, as quite often a power surge will damage the circuit board. E) Implement a static control program. Answer:
A) Incorrect. While contamination can be a major cause for electronic product failure, the problem would be evident year-round and not just during the fall and winter months. B) Incorrect. While more frequent inspections would help eliminate faulty components before they went to manufacturing, this would not be a seasonal problem but would be evident all year. C) Incorrect. Solid-state components do not generally have a “shelf life” if stored in the proper conditions. D) Incorrect. If a power surge was the cause of the problem, it either would occur at any time throughout the year or would occur more frequently in the summer months when lightning was common. E) Correct. Dry air, which is more common in cooler months, was causing additional static. Improper handling of the circuit boards sent the static to ground through the board and handler, damaging the board. By implementing humidity control and using individual ESD (electro-static discharge) products and equipment, the failure rate of the boards was reduced to a normal level year-round. _______________________________________________________________________________
Measuring Oxygen Content Challenge: Fred is looking for an instrument to measure the oxygen content of some vials. The amount of headspace in the vial is very crucial for his testing procedure. He needs an accurate meter that can read very low values and is easy to use. He doesn’t need any fancy, expensive functionality—he just needs to measure and store a few data points. Fred said, “The simpler the better!”
What would be the best meter for his application?
A) CheckMate II O2 benchtop analyzer (model 86490-20) measures from 10 ppm to 100% with an accuracy of 1% of reading, and it can log more than 10,000 test results. B) Handheld O2 analyzer (model 10360-20) measures from 0.1 to 100% with 1% accuracy, and has no datalogging capability. C) CheckPoint O2 analyzer (model 86490-00) measures from 0 to 100% with 0.1% from 0 to 5% and 2% from 5 to 100%. It also stores up to 10 readings to be recorder later. D) Benchtop O2 analyzer (model 10360-60) measures from 0.1 to 100% with 0.1% accuracy; has no datalogging capability. Answer:
A) Incorrect. This analyzer does not read low values. Plus, this benchtop unit is also much more expensive and expansive than the customer requires. B) Incorrect. Good range and accuracy, but does not have datalogging capability. C) Correct. This handheld analyzer fits all of Fred’s requirements. It is accurate and offers the needed measurement range. Plus it stores up to 10 readings. D) Incorrect. This benchtop analyzer is ideal for measuring the headspace in vials but offers no datalogging capability and is more expensive than simpler handheld units. _______________________________________________________________________________
Choosing a Refractometer Challenge: Amil is starting up his own company, Amil’s Amazing Winery. He needs a refractometer to measure the wine from 0 to 30% Brix. The refractometer will need to be used at various stages of his wine-making process, including when the grapes are heated to release the most flavor. Amil’s eyesight and patience are not what they used to be, so he needs a meter that is easy to read and simple to use.
What would be the best refractometer for Amil?
A) Brix refractometer with automatic temperature compensation B) Palette-style Brix refractometer with digital display and automatic temperature compensation, such as model 02940-62. C) Salt refractometer D) Handheld Wine refractometer with automatic temperature compensation and a 0 to 25% T.A. range. reads in T.A. Answer:
A) Incorrect. Even though this refractometer is easy to use and reads from 0 to 32% Brix, it would be hard for Amil to read the scale. B) Correct. This refractometer is perfect for growers, wineries, and grape must buyers! A simple scale selection key puts Brix, Titre Alcoometrique (T.A.), Oechsle, KMW (babo), and Baume scales at the customer’s fingertip. It features an easy-to-read digital display and is simple to use; place a few drops of sample on the prism, press the start key, and the measurement is displayed in just three seconds. The automatic temperature compensation handles the varying temperatures without the need for conversion tables. C) Incorrect. Customer did not want to measure salinity. D) Incorrect. This refractometer is for wine applications but it reads in T.A. (Titre Alcoometrirque). The customer would have to use a conversion to % Brix, which is not simple as he requested.
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