Category Archives: Acoustic Sound Surveys and Lighting Level Measurements – OSHA Safety ADA ATM Applications

Sound level surveys for noise, OSHA compliance and hearing safety

EMF Testing Indoor Air Quality Radon Gas Testing: 214.912.4691 Dallas – Houston – Austin – Fort Worth

Powerline Home Safe Distance Cell Phone RF Surveys

Cell Tower Site on High Voltage Power Line near homes in residential area in North Dallas – EMF Testing and Surveys

EMF Testing / Magnetic Field Survey & Safe Distance Measurement Services

EMF testing for those concerned about living near powerlines and feeders is available for commercial clients and limited residential with reports that range from verbal to complete reports with photo documentation and graphics. We also provide consultation on viable strategies and products for EMF protection. We travel all over Texas and cities in adjacent states including Dallas, Houston, Fort Worth, Austin, San Antonio and Oklahoma City.

RF (Radio Frequency) Scans and Evaluations – Maximum Permissible Exposure (MPE)

We test RF energy for frequency and amplitude in order to find sources and evaluate safety with respect to FCC regulatory, compliance and precautionary guidelines, and to determine potential interference issues between wireless routers, cell phone repeaters / boosters, Radio Frequency Identification (RFID) systems, and wireless microphone / audio / video data systems.

Magnetic / Electric / RF & EMF Shielding Consultations including proper grounding

If you have an issue with electromagnetic energy that is either a safety issue or causes equipment interference, we are fully qualified to assess, troubleshoot and make sound recommendations to fix or mitigate the situation.

Radon Gas Measurements & Surveys (Short / Long Term Testing)

With a background in radon and radiation safety, we are capable of evaluating and reporting on radon gas levels, how they compare with EPA standards and whether a mitigation solution is called for.

EMF Testing for Electrical Wiring Issues Indicated by Excessive EMF Fields

Whether you believe in the safety hazards of EMF or not, the most common source of high EMF fields inside the home is improper wiring which fails to conform to current NEC code. ScanTech can detect and direct repairs on electrical wiring that manifests as an abnormal magnetic field.

Preliminary Construction Surveys / Property Transfer Phase I Environmental Site Due Diligence Survey testing regarding Indoor Air Quality (IAQ) – EMF Consultation for Safety and potential EMI – Radon Testing for Multi-Family Dwellings and Commercial Buildings.

We are often called out to site before a structure or complex is erected in order to survey and communicate any possible issues and the potential impact of nearby power lines, substations, transformers, cell towers and other EMF/RF generating sources. We also make construction recommendations for minimizing electromagnetic field emissions for safety and electromagnetic Interference concerns with sensitive manufacturing and research equipment.

Indoor air quality testing for VOC levels regarding Certificate of Occupancy permits according to City of Dallas Green Ordinances. Also known as the 804.2 Post-Construction, Pre-Occupancy Baseline IAQ Testing which is a 4 hour test for 500 uG / m^3 or less of VOCs.

Magnetized & Radiation Contaminated Metals, Stone and Imported Products

ScanTech has been in the radiation survey business for over 10 years and is routinely called upon to investigate cases of suspected radioactive contamination and magnetized ferrous metals which can cause unusual issues. Our instrumentation includes several Geiger counters with capable of detecting Alpha and Beta particle emissions, X-Rays and includes specialized Gamma radiation scintillation detectors.

Weak Cell Phone Signal Reception Issues & Wireless LAN Problems / RFID Interference

Weak Cellular Phone (including 2G / 3G / 4G LTE) & Wireless Strength Measurements with consulting for correction / mitigation in commercial buildings, residential and multifamily properties with poor coverage, slow data rates and dropped calls for all major telecom and communications carriers including Sprint, T-Mobile, Verizon, AT&T for smartphones, tablets, iPads, etc. Radio Frequency Identification system troubleshooting and interference issues investigated. We also perform FCC RF Compliance surveys for MPE (Maximum Permissible Exposure) including rooftop antenna installations.

Implanted Biomedical Device EMF / EMI Measurement Compliance Surveys and Testing for Patient Safety

Medical Device Compliance Testing (Pacemakers, Implantable Defibrillators, ICD’s etc. – Medtronics, St. Jude Medical, Boston Scientific, Mortara) for individuals returning to work or home after implant surgery to identify potential hazards from AC/DC Magnetic and Electric Fields, Microwaves, RF and general EMI (Electromagnetic Interference).

Hospital Infant Anti-Abduction Security Systems

ScanTech troubleshoots RFID integrated systems designed to protect neonatal care facilities that employ systems such as Hugs by Stanley Healthcare and MyChild by McRoberts Security Technologies.

Electrostatic Discharge (ESD) Testing, Consulting And Evaluation for Commercial, Industrial and Biomedical Companies / Applications / Clients

We have the equipment to determine the sheet resistance of ESD flooring material and if anti-static grounding is working as well as the ability to identify troublesome materials and processes which can cause equipment malfunction and electric shock / fire / explosion hazards. We can also measure relative air ion counts, humidity and the direct DC static voltage on surfaces (positive or negative) up to 30,000 V to determine which objects in the environment may be damaging your static sensitive equipment.

Indoor Air Quality (IAQ) Surveys to Determine Relative Air Cleanliness PM2.5 / PM10 / HEPA Filtration Efficiency / Formaldehyde / VOC / CO2 (Carbon Dioxide) / O2 Oxygen % Concentration & Contamination for Commercial Building and Industrial / Occupational Atmosphere Evaluations with expertise in Nanotoxicology and Medical Environmental Illness Testing

We have time based datalogging air laser analysis available to characterize particulate matter such as small particle contaminants (down to 0.5 microns such as bacteria) and large particle counts (2.5 um and larger) for potential pollen, dust and mold detection which are also known as RSPs. (Respirable Suspended Particles) We can also check for formaldehyde concentrations and VOCs (Volatile Organic Compounds) levels from outgassing materials such as pressed wood flooring or glues and other binders.

Elevated CO2 (carbon dioxide) levels are indicative of Sick Building Syndrome and poor air exchange characteristics in a structure.

New nanomaterials on the market have raised concerns about the potential toxic effects of nanoparticles (such as carbon nanotubes, titanium dioxide, silver NPs, etc.) in particulate, aerosol, aqueous forms and their in-vivo effects.

Commercial, industrial, occupational health and limited residential applications.

OSHA Sound / Noise Level Surveys for Safety Audits

Sound (Commercial) & Industrial Safety field surveys and measurement including for acoustic OSHA sound and STC (Sound Transmission Class) noise levels / ordinances / testing (meeting ANSI & IEC Type 2 standards) to determine compliance and evaluate potential issues with excessive or disruptive noise.

Photometric Glare & Illumination (Lighting Level) Surveys for Safety, OSHA and City Ordinance Compliance

Photometric mapping to identify poor / insufficient / excessive illumination, security camera glare, ATM lighting security assessments, ADA lighting requirements / compliance, and privacy. Many cities have enacted ordinances which limit the amount of light emanating at the property line at night in foot candles. (fc) We can also measure lighting flicker rates which can cause headaches and other performance issues as well as evaluate possible disruption of circadian rhythms which lead to insomnia and lack of restful REM sleep.

Metallurgical Analysis & Consulting

Materials analysis for ferrous / non-ferrous metals / alloys. Tools and tool steel quality evaluations for carbon content. Also magnetic / RF / electric shielding capability, corrosion resistance, heat resistance, degree of temper, quench methods, elasticity, weathering, and electrical quality consulting. Metamaterial composite research for nanotechnology, biomedical, and exotic applications. (graphene, nanoparticles, carbon nanotubes, nanodiamond, etc.) Radioactivity testing for scrap metal or other suspected products.

LED Lighting vs. CFL and Incandescent Bulbs – A Considered Commentary Regarding EMF & EMI

Incandescent CFL LED Bulbs


In theory for many applications, yes, but in practice there are several problems with them. (here is a personal repost from a technical forum I belong to)

While the LED itself has a long MTBF (Mean Time Between Failure) the weak point in LED bulbs is the AC/DC converter circuitry. In the 7 LEDs I have bought so far in the past 4 years, I have had 3 failures. One of them actually failed in less than a month which is atrociously worse than virtually any incandescent I have ever owned. Another one had a flicker problem which developed in just over a year (I just replaced that one this month) and another burned up a regulator IC after a few years use. The inrush current and transients when you turn on an LED light can destroy cheap components over time just like any other bulb.

I have found the ones with ribbed cooling fins to work better, but it is hit and miss as to which manufacturer and model you should get as there is enough variation between manufacturing runs due to corners getting cut without warning.

LED lighting – just like SSD (Solid State Drives) it promises to be a huge leap in reliability but a manufacturer always seems to figure out a way to pinch pennies and wreck that longevity gap. (some SSDs used to have just as high or an higher a failure rate than conventional hard drives until the manufacturers got their failure modes worked out.

Don’t get me wrong – I like LED lighting and have been converting over for years, but be careful in your research.

And on that point there are a few good things left about incandescents in that they are better suited for accurate depictions of work in art galleries and museums. This is known as excellent color rendition, and they are typically rated around 98 % + while LEDs are typically in the low 80s. Also, they generally make better point source lighting which increases contrast when examining objects in fine detail. Finally, you have a warmer cast to the light which may be suitable for setting certain moods. (I have studied a little about lighting design)

I agreed that LEDs lighting is generally good and the direction we should go for MOST applications. But not all LED bulbs are created alike and you should consider the actual reliability based on manufacturer, model and manufacturing run. I have some that have lasted for years, another one didn’t even make it a month. (from a manufacturer / model that used to be good) Currently, I prefer to buy from a local store than online as it is easier to return if you get a dud. Incandescents and CFLs still have a very limited niche and I would only use them if you have a specific reason to do so. (and I do)

Bear in mind that the biggest jump in energy efficiency was from incandescents to CFLs, (a factor of 4) but from CFLs to LEDs the jump is not quite as dramatic. (a factor of 2) Also, the weak link in any LED bulb is the AC/DC converter built inside – ribbed heat sinks help a lot and I don’t think it hurts to look for Energy Star rated bulbs. Otherwise, you can wind up with an LED bulb that does not even have nearly the longevity of an incandescent. I have seen it too many times.

From my experience, the Cree models sold at Home Depot are pretty decent and the ratings I see on there look promising. Just hang on to your receipt and look at the color temperature in Kelvin (not the same as actual temperature) so that you can “color match” your lights. From 2700 – 3200 K has a yellow cast with the “hotter” temperatures like 4500 K and up looking more and more bluish white. Cooling ribs on the side promote longer life.

I prefer incandescents for the bathroom, but the higher temps for task lighting and elsewhere. If you have a mismatched set in a ceiling fan for instance, it will be pretty obvious.

I will keep you posted if I find a really reliable brand, but manufacturers can go from great to crappy pretty quick. (what you bought last year may no longer be that reliable)

From an EMF standpoint, the lower current draw of an LED is attractive as that also lowers the magnetic field intensity. However, there is more potential noise induced in the electrical wiring which can cause unexpected problems and anomalies with other electronic equipment.

A comment I found online from a neighbor (NextDoor.Com) related an issue with the Internet connection of a residence that malfunctioned due to this noise:

“I did have that problem before and after MANY different visits it was discovered that the box on my house was close to my security lights. I had put the new CFL/LED lights in. That seemed to interfere. They moved my box and things have been fine since.”

Sound Levels: Safety vs. Hearing Damage & Loss

Because sound pressure levels are measured on a logarithmic scale, (power ratios of 10) an increase in decibels beyond a certain point means that the energy impacted on the ear can quickly pass a threshold where damage can occur. As shown in the chart below, even an increase of 5 dB can greatly reduce the duration before hearing loss can occur.

Sound Levels vs. Physical Effects

Sound Levels vs. Physical Effects

Note that sound levels above 70 dB begin to interfere with voice communication, while 75 dB and above are generally characterized as annoying. (but dependent on frequency as shown below)

The general effects can be studied in the response table below:

Hearing Damage from Different Noise Levels

Hearing Damage from Different Noise Levels

Fortunately, sound pressure levels also decrease with the square of the distance, so moving twice as far away means that the power level decrease by a factor of 4. Bear in mind that 3 decibels (dB) reflects a change in power level by a factor of 2, with +3 dB being twice as loud and -3 dB being half as loud.

Sound Level Decrease with Distance

Sound Level Decrease with Distance

Also, the human ear does not have a “flat” frequency response – so frequencies at the extreme edges of hearing perception (from 20 Hz to 20,000 Hz) are not perceived to be as loud as those centered around 1 KHz – 3 KHz which is in the range of normal human speech.

Perceived Human Hearing vs. Frequency

Perceived Human Hearing vs. Frequency

Therefore, different measuring scales on sound meters are used to distinguish between “human” hearing (dBA) and “machine” hearing (dBC) which has a flatter frequency response.

Sound Weighting of dBA dBB and dBC Curves at different frequencies

Sound Weighting of dBA, dBB and dBC Curves at different frequencies