Arsenic contamination in groundwater is a worldwide problem. The existing portable field test kits can not provide accurate results when the arsenic concentration is around 10 μg L-1 or lower. This research first was focused on the development and validation of methods in which portable instrumentation, such as electrochemistry instruments or quartz crystal microbalances, could be used to accurately determine arsenic concentrations in water even when the concentration is below 10 μg L-1. A modified anodic stripping voltammetry (ASV) and cathodic stripping voltammetry (CSV) method with measurement at a microarray electrode manufactured by TraceDetect Inc. was developed. When the ASV method with a gold electrode was applied for real water analysis, the detection limit of arsenite was 2.2 μg L-1, and for arsenate was 0.13 μg L-1. In the CSV method the more commonly used hanging mercury drop electrode was replaced with a mercury film array electrode. Under the optimum condition, this method had a detection limit for arsenite of 0.58 μg L-1 and for arsenate of 2.7 μg L-1. A method for the determination of arsenic using a quartz crystal microbalance was developed in which the crystal surface was modified in situ by dithiolthreitol, an arsenite-selective ingand. The method was applied to real water sample analysis with a limit of 0.6 μg L-1. The second was concerned with an investigation of the kinetics of the reactions that are the basis of several currently available field test kits (as exemplified by the Hach Kit) using inductively coupled plasma mass spectrometry (ICP-MS) with the goal of improving the performance of the test kit. The time for arsine gas reaches to the maximum concentration in the headspace of the vessel was about 60 min without continuous stirring and only 20% of arsenic was absorbed on the test strip. To speed up the arsine generation, continuous stirring condition can be applied. It also made more arsine absorbed on the test strip. The SEM study proves the structure of the darker colored compound. For the lighter colored compounds, the information is not enough to make a conclusion.

In lighting design, several different variables are measured, such as illuminance. Measuring these values requires different types of measuring instruments, either static measuring instruments or portable measuring instruments. Depending on the make, the same type of measurement can be measured in different ways. A static measuring instrument is usually measured one time at a specific location, while a portable measuring instrument can, for example, measure every minute or every ten minutes for an extended period. With constant research and technological development, the measurement of lighting variables has become more relevant. It is problematic to conduct experiments with a lack of consistent and accurate methods when measuring light. It is important to have the right conditions for a measurement in order for the results to be of good quality. The purpose of this study is to investigate differences between different static and portable measuring instruments used to describe the exposed illuminance and the physical activity. This is done through a pilot study. The pilot study was conducted using an experimental quantitative method with two participants during one day in four different measurement occasions with six different measuring instruments, the measuring instruments being measured in vertical, horizontal and flexible positions. The analysis showed that the results largely depended on whether a static or portable measuring instrument was used. The results also showed that depending on what position the measuring instruments measure from, the results vary. Based on the results, the conclusion is that the closer to eye level one can get, the more relevant the results are. For further research, all the measuring instruments used in the study should be calibrated prior to implementation. For example, it is important to examine the sensitivity of the measuring instruments when measuring indoors and outdoors. More participants, more measurements and more contexts would have been preferable for further research.

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Volatile Organic Compounds (VOCs) are commonly used as indicators of an organism's health, among other factors. Traditionally, gas chromatographs (GC) are used to classify these but are prohibitively expensive and impractical for field use. This thesis outlines the motivations, design, construction, and characterization of a portable GC. This proof-of-concept uses off-the-shelf components to show that the production of a device is feasible. It was able to successfully generate carrier gas from the surrounding air via filtration by activated carbon fiber filters. It was also able to reliably produce distinguishable peaks for acetone and hexane at retention times that were reasonable for a prototype system. With some modifications, this system has the strong potential for long-term implementation in the field.