Balances are among the most commonly used instruments in any laboratory. From sample weighing to check weighing and from weighing miniscule amounts up to kilograms, weighing results always greatly depend on the performance of the balance. There are regular balances checkups that ensure functioning and accurate balances but operator handling also has a great influence on weighing performance.
Proper weighing technique directly affects the experiment success and repeatability. Below are a few simple things that will greatly improve weighing performance.
• Avoid electrostatic charges: Weighing vessels and samples may become electrostatically charged, particularly in dry air. Metal is the best material for weighing vessels, and glass is preferable to plastic as it is less susceptible to electrostatic charge. Reduce weighing errors by increasing atmospheric moisture and using anti-static kits.
• Avoid vibrations and drafts: Ideally, the balance room should be situated in the most vibration¬-free area of the building, and accessed through a sliding door. Locate the balance away from doors and areas of high traffic to avoid drafts. Do not weigh near windows or near radiators, which can cause strong air currents that may interfere with the balance. Avoid placing the balance in the air flow of air conditioning units or devices with fans, such as computers.
• Be aware of absorption / evaporation effects: Hygroscopic samples gain weight when they absorb atmospheric moisture while volatile samples evaporate and show a weight loss. Use clean, dry, stoppered weighing vessels with narrow necks. Keep samples in closed containers at all times.
• Reduce the influence of body heat: Heat radiating from an operator’s body may have an adverse effect on weighing measurements. Where possible, avoid using the hands to place the weighing vessel in the weighing chamber, as this can alter temperature and atmospheric humidity. Wear a lab coat to reduce the effect of the body’s surface temperature.
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METTLER TOLEDO specializes in the area of precision instruments for professional use. METTLER TOLEDO laboratory instruments are used in research, scientific, drug discovery, and quality control labs, amongst many others in the pharmaceutical, chemical, food and cosmetics industries. METTLER TOLEDO comprehensive industrial solutions cover the various steps in a host of manufacturing processes at many of the same customers that laboratory serves. Solutions range from receiving raw materials through various manufacturing processes, in-line process control and end-of-line packaging control, to logistics and shipping. Increasingly, these solutions are fully integrated into the customer's IT environment, helping automate their workflows. In food retail, our offering for fresh food management ranges from receiving and pre-packaging, to in-store solutions for self-service departments, deli counters, and checkout terminals.