Posts by Rachel Kohn
Selecting a Moisture Analyzer Drying Process
Infrared moisture analyzers such as the new Kern MLS-C now available from Tovatech use the thermogravimetric drying process to calculate the moisture content of a sample. Also called the loss of weight on drying (LOD) method, the drying process compares the weight of a sample after drying to the weight before drying. The difference is displayed the percent of moisture in the sample. This is a critical quality control step to confirm that commercial bulk drying ovens are performing to specification and that the product meets regulatory or industry standards for moisture content.
Selecting the Moisture Balance Drying Mode
Because products react differently to heat employed during the drying process, laboratory moisture balances can be programmed for different drying modes or drying profiles. These can be classified as standard, rapid, step and gentle. The mode is graphically displayed on the control panel. Here is a general description of each:
- Standard
Why Moisture Content Matters
Moisture content, as we have pointed out in many of our posts, is important for a variety of reasons, many of which have to do with quality control, product shelf life and fair pricing. Controlling moisture content can occur at several points along the processing line and usually involves the use of drying ovens, some of which are equipped with moisture sensing devices to reduce the percentage of moisture to target levels. Moisture levels are set by industry and trade associations, and by government agencies. It is up to manufacturers to verify moisture content.
Picking up on our opening sentence, an example of moisture’s effect on quality is exemplified by products as basic as sugar, table salt and bagged cement. All three are hygroscopic – exhibiting a tendency to absorb moisture. A target moisture standard for sugar is 11.9%, … Read the rest
Scale with Remote Display Gives 0.1g Resolution
The separate weighing platform of the new ILS 50K and companion ILS 30K, 50 kg and 30 kg capacity industrial scales, each with 0.1 g resolution and a 5 g minimum load, makes these laboratory balances ideal quality control instruments for accurately weighing heavy toxic, odor-emitting or contaminated samples under fume hoods or in glove bags. The rugged stainless steel weighing platform handles compact high-density samples such as drilled cores and sawed beams of concrete, and is connected to the control and display unit by a cable approximately 1 meter long.
Now available from Tovatech, these lab scales are offered with external calibration (the ILS configuration using a separately purchased 30 or 50 kg weight) or with automatic internal calibration (the ILJ configuration). ILJ models will re-calibrate every 3 hours or when there is a temperature change of 3⁰C or more.… Read the rest
How to Store Hepatitis Vaccine
Proper refrigerated storage of hepatitis vaccines is essential to maintain potency as well as to avoid substantial monetary losses due to lack of potency and the time and inconvenience to revaccinate patients. Proper vaccine storage is also required for providers participating in the Adult Hepatitis Vaccine Project, which is equivalent to the Vaccines for Children program. AHVP compliance is necessary for providers participating in the project and receiving state-supplied vaccines.
Step 1: Calculate Vaccine Storage Requirements
Healthcare providers should calculate the number of hepatitis vaccines they will store in their refrigerator. This is done by adding the number of public and private vaccines on hand from the last order and multiplying that number by 1.25 to determine total doses. Using the table below match this number with the minimum cubic feet required for storage.
|
Maximum doses | Minimum cubic feet |
|
1000-2000 |
40 |
Ultrasonic Cleaner Hints
You know the routine. Chances are you’ve done it yourself. If the recipe calls for a tablespoon of oregano you think well, two tablespoons will make it taste better. If directions say bake at 325⁰F you think well, if I bake at 425⁰F it will be done faster. That’s not the always the case for recipes and it certainly is not the case when you operate an ultrasonic cleaner.
How to Prepare Ultrasonic Cleaning Solution from Concentrate
This is the recipe portion of our introductory paragraph. Ultrasonic cleaning solution concentrates are formulated to be diluted with a specific amount of water. An example is the widely used general purpose elma tec A4 concentrate where the recommendation is dilution to 2% – 5% with water.
Now on the often mistaken theory of “more is better” you may be tempted to dump in … Read the rest
Time to Upgrade your Vaccine Refrigerator?
As of October 2013 predictions on the severity of the 2013-2014 flu season have not firmed according to the CDC, which notes on its website “Although epidemics of flu happen every year, the timing, severity, and length of the season varies from one year to another.” The CDC also states that flu activity commonly peaks in the U.S. in January or February but can run from October to May.*
While timing, strains and severity are of concern to everyone, dispensers of flu shots must continually evaluate the performance of their vaccine refrigerators and vaccine freezers to be certain that they comply with CDC vaccine storage recommendations. This is especially important if you participate in the vaccines for children (VFC) program. To finance vaccine refrigeration upgrades check your remaining budget for 2013 or include it in the 2014 budget.
Key Points for Proper Vaccine Storage… Read the rest
Final Step Cleaning in Metal Fabricating
Product cleanliness is an important criterion for machine shops and metal fabricating shops producing parts meeting extremely tight tolerances. Removing all traces of cutting oils, dust, chips, turnings, polishing residues and other contaminants is necessary to ready newly fabricated and machined parts for shipping. Depending on the size of your facility an industrial or benchtop ultrasonic cleaner is your best solution to achieve optimum parts cleaning.
Ultrasonic cleaning is especially effective for fabricated or machined parts with intricate designs because the process acts on all surfaces immersed in specially formulated water-based biodegradable ultrasonic cleaning solutions. Hand scrubbing with brushes in solvent-filled wash tanks not only is time consuming; it cannot reach small crevices, blind holes and other tight spots or restricted areas. Moreover, solvent baths can be a health hazard and present disposal challenges.
How Ultrasonic Cleaners Work
Cleaning is accomplished by what is called cavitation. This is the implosion … Read the rest
How to Select a Digital Bench Scale
A bench scale is generally placed on – you guessed it – a bench or a countertop. A distinguishing characteristic of digital bench scales vs. platform scales is that the controls and display are part of the unit whereas a platform scale display is separate from the weighing platform.
Kern bench scales available from Tovatech have weighing ranges from 6 to 60 kg allowing them to support a broad range of applications. Most are available with standard disposable battery power or optional rechargeable battery power in addition to line power. This is a big plus if you need portability or perform weighing operations beyond the reach of an outlet.
Specifying Digital Bench Scales
This is a straightforward process until it comes to added bells and whistles you may require for your operations. First the basics:
At the top of your list is the maximum weight the scale can handle. If … Read the rest
Specifying Tips for Industrial Ultrasonic Cleaners
First of all, for the purpose of this post let’s define an industrial ultrasonic cleaner. Most simply they are floor mounted or wheel mounted when compared with tabletop ultrasonic cleaners. Basic ultrasonic cleaning technology is the same. The size of the parts being cleaned is high on the list of specification criteria, but also important are the steps employed to achieve the desired level of cleanliness. An example of where an industrial unit might be called for is our post on cleaning vehicle transmissions.
Cleaning Tank Size
Ultrasonic cleaning tank size is governed by the part or parts being cleaned. This also determines the amount of ultrasonic cleaning solution required to fill the tank – allowing for displacement due to parts being cleaned.
Tank size must take into account working depth to assure that parts being … Read the rest
What you should know about Lab Refrigerator Alarms
In this post we take a bit of liberty with Murphy’s Law (If something can go wrong it will) and apply it to safe storage of pharmaceuticals, biologicals and other temperature-sensitive products in scientific refrigerators and freezers. Indeed, many of our posts deal with temperature control and temperature monitoring/recording systems for this equipment. Here we focus on the third part of the equation: laboratory refrigerator and freezer temperature alarming systems.
Why Temperature Alarms are Critical
What can go wrong? Perhaps a power failure is first to come to mind. If your facility does not have an emergency generator that immediately comes on line you need a backup plan to … Read the rest