Micro vibration is very different from standard “vibration”. We are experts in both fields, however micro-vibration monitoring requires entirely different equipment and a different set of skills and understanding to interpret the data.
Micro vibrations usually have the most detrimental impact in laboratory environments where sensitive equipment such as electron microscopes, mass spectrometers, NMRs, or MRIs are being used. This equipment requires isolation from internal and external movement of the floor and usually requires specific construction and installation guidelines. In these environments, floor vibrations down to 0.1 nanometer peak to peak, 1 micro-g RMS or 0.8 micro-in./s RMS, from 0.4 Hz to 4 kHz can be monitored continuously over long periods of time and are often monitored permanently. Longer term samples provide better resolution for diagnostics than a one-time site visit, and continuous or permanent monitoring will alert the responsible parties to any unexpected new or increased vibration that would not have been detected otherwise.
The NIH (National Institutes of Health) Office of Research Facilities provides information and guidelines on their website about vibration in biomedical and animal research facilities and on highly sensitive equipment like electron microscopes. These are important considerations which are often overlooked.
We provide micro-vibration monitoring on site for both new construction and for existing facilities to determine the viability of equipment installation locations. It is better to guarantee that the laboratory environment is suitable for the equipment before it is moved or installed than after it is in use and producing faulty results or bad data.
We also work with architects and planners in the schematic design phase with feasibility baseline site surveys to achieve proper vibration isolation of ultra-sensitive equipment before installation, and provide conformance or follow-up testing. Our measurement systems are wireless and either send data to our cloud or collect data internally. Sound and vibration data can be coupled to video data if necessary. When building structures require dynamic analysis, we can provide Finite Element Analysis as well.
According to the manufacturers’ documentation, most environmental scanning electron microscopes and transmission electron microscopes require a floor vibration site survey before installation. This stipulation is outlined in the operation manuals of the equipment and is meant to alert the end user to the potential for issues that can arise from insufficient structural isolation. Vibration in either the vertical or horizontal direction within the installation environment will contribute to the spread of focus in the image and will affect the potential resolution of the equipment.
Typically, a company’s investment in a mass spectrometer (or multiple mass spectrometers) is fairly significant. The high cost of the equipment is usually an investment in the research and reputation of the company who is spending the money. Too much vibration- even of a temporary nature can shorten the life of a mass spectrometer, which is why it is important to address vibration issues up front or perform testing and analysis of the laboratory environment if there are suspicions that vibration may be present and causing faulty data. As technology in mass spectroscopy equipment advances, the machines are capable of producing increasingly finer spectra. This makes them more susceptible to micro vibration and makes them susceptible to vibrations that they may not have been affected by previously.
Nuclear Magnetic Resonance machines are highly-specialized and very expensive. The cost for a single machine can be over $1 million. These machines are highly sensitive to structural and floor vibrations during operation, so their location and the long-term viability of the laboratory environment is of particular importance. Any disturbance to the building or floor structure will introduce unwanted noise which interferes with the signal of interest. Ideally, the installation of these high-cost, highly sensitive pieces of equipment should be on a solid ground-floor slab, but that is not always possible. Whatever the installation conditions are, micro-vibration monitoring of the proposed location should be part of the process before the equipment goes in, and any issues with vibration will need to be addressed if proper functioning of the machine is expected.
LIVE ANIMAL LABS
Researchers know the importance of controlling the level of environmental stress during research studies in order to produce accurate and reliable results in live animal labs. Breeding habits and behavior in animals can be affected by the level of stress produced from the environment in which they are kept. Micro-vibrations and ultra-sonic sound are two stress factors, undetectable by humans that are caused by a wide range of lab equipment like label readers, light sensors, and even laptop computers. Interference from these stressors can have a devastating effect on animals like mice, which use ultra-sonic sounds to communicate to attract mates or warn of predators. Without proper isolation from stress factors, mice can produce inconclusive results in studies or stop breeding all together. Long-term or permanent monitoring of vibrations and ultra-sonic noise levels, similar to monitoring of temperature, humidity, and other environmental factors is often recommended.
We are a proud member of the American Association for Laboratory Animal Science (AALAS) an organization of professionals that advances responsible laboratory animal care and use to benefit people and animals.
MRI machines are extremely vulnerable to the effects of micro vibration. Structure-borne and floor vibrations will have an impact on the accuracy of the imaging, so it is crucial that the installation environment is appropriately isolated and designed properly for use as an MRI scanning suite. The equipment itself is expensive and the users and patients count on it for accurate and reliable results. Micro-vibration testing will provide assurances that the site is within the allowable manufacturer’s limits for proper functioning of their equipment. Measurements and analysis should be performed before installation and any issues need to be addressed before the equipment is installed.
The built environment changes over time. After installation, long-term monitoring will provide a safety net for any unforeseen occurrences of vibration. Additions, renovations, the degradation of mechanical systems, re-routing of traffic, or other external conditions can all have an affect on the building or floor structure that may introduce new and unacceptable levels of vibration into a space that was once tested to be under the allowable threshold.