Your forehead is about to get a lot of action. Is it greasy? You may want to wipe that sweat off. In the age of COVID, our forehead will become the target of fever spot checks. Thermal cameras and non-contact infrared thermometers will get deployed in an effort to prevent people with a fever from entering into an area where they may infect others. The only question is, do these temperature-sensing technologies actually work?
Be sure to first check the manufacturer's instructions, but most digital thermometers can be disinfected by either using rubbing alcohol that's at least 60% alcohol to kill bacteria, or a bleach or alcohol wipe.
Thermometers may be described as empirical or absolute. Absolute thermometers are calibrated numerically by the thermodynamic absolute temperature scale. Empirical thermometers are not in general necessarily in exact agreement with absolute thermometers as to their numerical scale readings, but to qualify as thermometers at all they must agree with absolute thermometers and with each other in the following way: given any two bodies isolated in their separate respective thermodynamic equilibrium states, all thermometers agree as to which of the two has the higher temperature, or that the two have equal temperatures. For any two empirical thermometers, this does not require that the relation between their numerical scale readings be linear, but it does require that relation to be strictly monotonic. This is a fundamental character of temperature and thermometers.
The precision or resolution of a thermometer is simply to what fraction of a degree it is possible to make a reading. For high temperature work it may only be possible to measure to the nearest 10 °C or more. Clinical thermometers and many electronic thermometers are usually readable to 0.1 °C. Special instruments can give readings to one thousandth of a degree. However, this precision does not mean the reading is true or accurate, it only means that very small changes can be observed.
The liquid used can be pure ethanol, toluene, kerosene or isoamyl acetate, depending on manufacturer and working temperature range. Since these are transparent, the liquid is made more visible by the addition of a red or blue dye. One half of the glass containing the capillary is usually enamelled white or yellow to give a background for reading the scale.
Air temperature is measured with thermometers. Common thermometers consist of a glass rod with a very thin tube in it. The tube contains a liquid that is supplied from a reservoir, or "bulb," at the base of the thermometer. Sometimes the liquid is mercury, and sometimes it is red-colored alcohol. As the temperature of the liquid in the bulb rises, the liquid expands. As the liquid expands, it rises up in the tube. The tube is marked with a scale, in degrees Fahrenheit or in degrees Celsius.
Every thermometer we tried bounced around within a small range from measurement to measurement. In the end, though, most of the thermometers we tested gave readings that were acceptably consistent. Our picks stand out from the pack on the three most important fronts in these strange times: accuracy, consistency, and availability.
And that was in a tank without any surface movement. I found that filters pushed the floating thermometers around until they became stuck in the corner at the rear of the tank. If you have background plants or decorations, then these will block your ability to read this thermometer.
The reason for including these specific thermometers is that they need to be accurate and durable. Not only that, but these types of thermometers are often recommended by hobbyists and even sold in fish stores.
Even digital thermometers and probes with a different design struggled when it came to accuracy. The Lifegard Aquatics Little Time or Temp would randomly fluctuate while the Marina Aqua-Minder showed a reading that was 6°F higher than the actual temperature, making it the worst performing thermometer we tested.
I must admit ian,thermometers are driving me crazy.Iam trying to find a accurate digital wired probe so we can see on the side of tank all the time.I have 5 of them and like you said they are all over the place with there readings,i also have a glass submersible that is more accurate than my jw smarttemp by 1 degree.I just purchaced a cooking fixed probe that is brilliant and matches my set heaters and glass submersible spot on.As our eyes are not what they used to be, we woulddearly love a digital wired probe that we can see clearly on the front of our tank.I just can not find one that is even close to being accurate.If you can suggest a brand it would be greatly appreciated.Thank you very much for a great run down on fish tank thermometers.Regards,Gary.
Digital weather stations often have a smart-home integration capability. As long as they run on the same Wi-Fi network as other devices, these thermometers can connect to a digital assistant like Google Assistant or Amazon Alexa. From there, users can use voice control to monitor the environment in and around a home.
Don, thank you for your great comment. The Vinometer is a somewhat accurate way to read alcohol levels in a finished wine. The biggest problem with them, and the reason we prefer the use of a hydrometer, is because they are not accurate at all with wines that have residual sugar left in them. The wine needs to be bone dry for an accurate reading. And for wines that are noticeably sweet, the readings are off the chart.
To measure temperature we use a thermometer, you probably have one of these at home for taking your temperature when you are feeling poorly. We used to use thermometers that had mercury in them, but all of these are no longer used as mercury is dangerous if it were to leak out or the thermometer was to break. Instead we now use digital thermometers or alcohol thermometers.
We also use radar to measure rain. Radar was developed during World War II to detect enemy transport, such as planes, ships and submarines, before it was realised that it can also be used to see where rain is falling. We now have 18 radar stations across the British Isles, including those in the Republic of Ireland and Channel Islands, scanning the skies for rain every 5 minutes. Radar works similarly to other pieces of equipment we've already looked at; the radar sends out waves and measure how long it takes for these to bounce back, which tells us where the rain is depending on how long it takes to come back. Radar can also tell us how heavy the rain is and we can use this to estimate the rain rates at the ground.
We also need to know the snow depth at the ground, not just if it's falling out of the sky. To measure the snow depth all you need is a ruler! To get an accurate reading of the snow depth you need to choose a good point to take a reading, this would be somewhere flat that isn't sheltered by trees or buildings and is grassy. We measure over grass and not brick or concrete as these materials are warmer than grassy surfaces so will make the snow melt quicker.
Scientists refer to the tendency of matter to change volume as a result of a temperature change as "thermal expansion and contraction." Gases expand and contract drastically. Fluids expand and contract, too, but their volume change is more moderate. Even solids change volume when they are heated or chilled. For example, bridges are a little bit longer on a hot day. The change in volume of solids is too subtle, though, to work in an everyday thermometer. Now that you understand more about liquid thermometers, it's time to get started actually making one!
The second principle is to keep everything clean. Bacteria present on raw meat and poultry products can be easily spread to other foods by juices dripping from packages, hands, or utensils. This is called cross-contamination. When transporting raw meat or poultry, double wrap or place the packages in plastic bags to prevent juices from the raw product from dripping on other foods. Always wash your hands before and after handling food, and don't use the same platter and utensils for raw and cooked meat and poultry. Soap and water are essential to cleanliness, so if you are going somewhere that will not have running water, bring it with you or bring hand sanitizer that contains at least 60% alcohol. You can also use disposable, alcohol-based wipes to sanitize your hands.
Employers will need to consider what supplies may be needed to facilitate a smooth return to work, keeping in mind the CDC guidelines, as well as applicable state and local return to work orders. For example, Delaware is requiring that employers provide employees with a face covering to wear while working in areas open to the general public and areas in which coming within 6 feet of other staff is likely. Thus, employers should pre-order (taking shipping time into consideration) necessary or required products, which will likely include hand sanitizer, paper goods, sanitizing wipes, bottled water, face masks, gloves, etc. Special cleaners may need to be ordered, and personal protective equipment (gowns, gloves, masks) may be needed for any individuals who clean or remove trash. Depending on what state and local governments require, preparations for medical testing, such as electronic or sanitary thermometers, should be considered. In addition, employers should monitor what may be required for on-site COVID-19 testing and/or antibody testing. Employers should consider what supplies will allow employees to minimize time spent in common areas. Additionally, individual workspaces should be prepared with necessary supplies to eliminate the need for employees congregating in a supply room. Employers may want to implement a bring-your-own-refrigerated-lunchbox policy to limit use of common refrigerators. Employers will need to determine if changes need to be made regarding lactation rooms to ensure strict compliance with thorough sanitization protocols. Employers will also have to consider adding additional hand washing stations. Finally, employers should prepare signage and other instructions for employees and visitors to their facilities to avoid any confusion related to containment practices upon reopening. 2b1af7f3a8