Choosing a fume hood can seem like a daunting task. There are so many options to choose from and so much information to gather in order to make an informed decision. But fear not, help is at hand! First, spend a few minutes answering these questions. When you have answered all seven questions, you have successfully established the criteria necessary for choosing a fume hood system. Second, review the answers with the Application Specialist and we will make product recommendations based on your answers.

Humidity measurement and control is called for in a wide variety of industrial applications. Each application has a different set of requirements for humidity instruments, such as required measurement range, tolerance to extreme temperature and pressure conditions, ability to recover from condensation, ability to operate in hazardous environments, and options for installation and calibration. There is no single device that is suitable for all needs. In fact, the range of available equipment is quite large, varying both in cost and quality.

Spectrometers, or spectrophotometers, are analytical instruments used to identify or confirm the chemical species, chemical structure, or concentration of substances in a sample. Spectrophotometers will emit an energy source to pass through a solution and measure light intensity at different wavelengths. If the solution is high in molecular concentration, then more light will be absorbed. In most cases, a sample submitted for spectrometric analysis must be very pure in order to avoid poor or contaminated results. Spectrometers are generally comprised of a light or energy source (typically a lamp), a filter (or monochromator) to set desired wavelengths of which to read, a place for cuvettes or blanks, and a radiation detector (or phototube) to convert the energy received during the experiment into a measurable signal.

 Electrode Components

Most pH electrodes are combination electrodes. An electrode comprises two main elements. One element is a sensing half-cell and the other is a reference half-cell. Both half-cell units must be used together to complete the pH circuit in order to get a pH measurement. The sensing half-cell is the portion of the electrode that is responsible for the measurement portion in the system; think of this as the positive (+) end of the circuit. This portion of the electrode typically contains a membrane that is sensitive to the change in the pH of the solution being measured. The reference half-cell provides a stable reference potential that is needed for pH measurement; think of this as the negative (-) end of the circuit.