Formaldehyde Meter / Formaldehyde Tester

Formaldehyde is a chemical compound that has many uses and is therefore produced industrially in large quantities. Formaldehyde is very reactive and is also produced during natural processes. It occurs naturally as an intermediate product in the metabolism of mammals, as well as in wood, in the atmosphere, and in many foods. Formaldehyde is easily soluble in water, ethanol and diethyl ether. The concentration in outdoor air within Germany is usually below 0.01 mg/m3 if no emission sources from the environment cause the value to rise.

The chemical molecular formula is: CH₂O. It is also simplified as H-CHO or HCHO.

Formaldehyde has a boiling point of minus 19 °C. Under standard conditions, it is a colourless, sour pungent-smelling gas the concentration of which in air can be determined with a formaldehyde meter. The odour threshold for people who are not sensitive to odours is about 0.14 ppm on average. However, adverse health effects can occur at much lower concentrations. In addition, the odour can be masked by other odours and is often perceived as unpleasant but not always dangerous.

As with other air pollutants in the indoor air, the limit value for formaldehyde has not been set for a single measured value. Instead, the formaldehyde measuring device must be used to determine the average value for the specified time period. The short-term measurements usually run for 30 minutes, the long-term measurements for 8 or 24 hours. The specified limit values for short- and long-term measurements differ considerably, since the long-term measurements also include the ventilation cycles with lower values.

Formaldehyde measuring device for orienting measurements
A mobile formaldehyde measuring device with an electrochemical sensor is often used for orienting measurements. These devices are easy to operate, the time required for the measurement is very low and the measured value is displayed directly on site. In contrast to the measurement methods with sampling and laboratory evaluation, these measurements are inexpensive and can be repeated as often as required.

Orienting measurements with the mobile formaldehyde measuring device in indoor rooms are quite suitable to clarify whether and under which conditions the increased formaldehyde loads are present. They can be used to investigate homes, schools and kindergartens, as well as offices, workshops and other workplaces.

With the measurement system for risk assessment of the accident insurance institutions (MGU), the measurement procedures for indoor measurements were developed based on DIN EN ISO 16017-1. The uniform application of the measurement procedure can the measurement inaccuracies and increase the comparability of the measurement results. The measurements can also be used to identify and evaluate the sources of the formaldehyde emissions.

Formaldehyde indoors can outgas not only from permanently installed building materials, but also from furniture, indoor textiles, toys, and packaging materials. The non-fixed materials can also be tested with the formaldehyde meter in a separate room. If several measurements in the previously unpolluted room show values that are too high, the parts can be reclaimed, disposed of or specially treated. Materials whose formaldehyde emissions decrease can also be stored separately until the tolerable levels are reached.

Formaldehyde measuring device for limit value monitoring
In order to be able to check the compliance with the limit values, the measuring methods are required that precisely and reliably determine the formaldehyde content. In many processes which involve taking the individual samples, the formaldehyde content is first determined in the laboratory with the help of the formaldehyde measuring instrument. Either the measurements are made directly in the gas phase or the formaldehyde is first enriched in the liquid or solid phase. The measurement results are hardly influenced by the presence of other gases. However, the major disadvantages of these laboratory methods are the time and cost involved and the fact that only random samples can be evaluated.

Photoacoustic or infrared spectrometers are mainly used as the formaldehyde measuring instruments for permanent monitoring of emissions. The photoacoustic measuring principle uses the pulsating laser light to transfer energy to the gas molecules, thereby generating pressure fluctuations in the gas sample. The more molecules are present, the stronger are the resulting pressure waves. During the measurement by means of the Infrared spectroscopy, the specific absorption behaviour of the molecules is used. Many of the instruments are designed to determine the concentrations of a variety of organic and inorganic gases during one measurement run.

Measuring range and accuracy of the formaldehyde meter
The measuring range of the instrument should meet the requirements of the intended application. Small measuring ranges are sufficient for the measurements in living and working spaces, where the compliance with the limit values for breathing air is required. They can be carried out with the formaldehyde measuring instrument whose measuring range only extends to a maximum value of one milliliter of formaldehyde per cubic meter of air.

Limit and guide values for formaldehyde in the breathing air

The most common units of measurement for formaldehyde in air are parts per million (ppm) and milligrams per cubic meter or micrograms per cubic meter. Some models of the formaldehyde meters offer both units. However, the conversion factor is usually fixed and does not take into account the actual room climate.

The wider the measuring range is, the higher the deviation of the measured values is as a rule, if the specified accuracy refers to the measuring range. For a measuring range of 2 ppm, an accuracy of ±5 percent from the measuring range means that over the entire measuring range, the deviations in the measurement result of 0.1 ppm upwards and downwards are permissible. A formaldehyde content of 0.15 ppm may therefore be indicated with values between 0.05 ppm and 0.25 ppm.

With a measuring range of 2 mg/m3 and an accuracy of ±15 percent relative to the measured value, the formaldehyde measuring instrument may indicate the values from 0.085 mg/m3 to 0.115 mg/m3 for a formaldehyde concentration of 0.1 mg/m3. When selecting an instrument, it is important to ensure that the accuracy is sufficient for the range of values to be monitored. For precise measurements, it is also important that any cross-sensitivities of the measuring principle are considered.

Very often people think that is they are not involved in industry and have nothing to do with chemicals in their daily life, they are safe from their negative impact. It is a pity but it turns out to be a false impression. “Formaldehyde” is a word familiar to everyone, but not always people know for sure what it is and where this substance can be found. In fact, it is a colorless gas (detectable by a formaldehyde meter), with a very strong unpleasant smell, which may have a negative influence on the humans (breathing, skin, nervous system etc.). Since the gas has a strong smell, one may say that if there is no smell, there is no danger, but for safety reasons a measurement with a formaldehyde meter / formaldehyde tester is indispensable. For sure, the higher the concentration, the stronger the smell, and the more evident it is that the substance is present in the air. But, even if there is no smell, it not always means that the atmosphere and surrounding is absolutely clean and safe.

Formaldehyde is often used in the production of formaldehyde resins, which, in their turn, are used for composite materials, glues, adhesives, varnishes etc. In fact, formaldehyde is found in many things which people use daily: various glues, pressed wood, insulating materials, plywood, furniture, personal care products, nail polish, deodorant sprays, air fresheners, stain removers, various household chemicals, etc.

It is an open fact that it is definitely used in the medical institutions and labs as a preservative or disinfector, in biology, agriculture, or in industry, as, for example, the mixture containing formaldehyde, makes the production of furniture cheaper. The sad truth is that it happens that, in the long run, our houses, soil, water etc. are not protected from this substance at all that’s why it must be measured by a formaldehyde meter. That is why it is so important to know how much of the dangerous substance is present in the air, how to reduce it and what to do to even eliminate it.

Formaldehyde is one of the most widely spread contaminants. Inhaling is the main way how it gets into the body. This substance is soluble and makes solutions with water or alcohol. CH2O is a formula, familiar from the chemistry lessons, but during those lessons not each of us thought that this substance belongs to the class “highly dangerous”.

Among the signs of formaldehyde poisoning are: allergic reactions, tumors, mutations in the body, unpleasant feeling in the nose and eyes, asthma, fatigue, headaches. Sometimes the consequences turn out to be much more aggravating and bring to terminal diseases. The same level of exposure to formaldehyde may bring to various reactions, since not all people react to the presence of the chemical in the same way. But even if somebody is more resistant than the other, it does not mean that daily use of things, which are evaporating the formaldehyde particles, or being in the environment, where the concentration of the substance reaches a very high level, should not be avoided. Formaldehyde accumulates in the body slowly and it is very difficult to excrete the toxic accumulations later.

Sewage waters, rain, air we breathe (especially in big cities and industrial areas), furniture we use, exhaust, smog – we are surrounded by the “dangerous” things and it seems to be impossible to isolate ourselves from their subsequent negative impact. Among the simplest things that can be taken as measures of precaution are: to spend as little time as possible in the industrial areas or the areas with very dense traffic, to pay a special attention to the quality of things which we buy (cheap price is not always the best choice, and initial saving turns out to be much more “expensive” afterwards), to air the room as often as possible, and to decorate your office or house with houseplants, which have a capacity to absorb the harmful vapors. The biggest part of the life time, the majority of people spend inside and that is why the microclimate created inside and the quality of the air should be moved to the foreground. Temperature in the room, level of humidity, heating, gas stoves, smokers – all these factors “contribute” to deterioration of the surrounding atmosphere. The warmer the temperature, the more intensive evaporation of formaldehyde is, that is why warm and hot weather is especially favorable for that. One of the modern solutions may be an installation of the air cleaners or application of formaldehyde meter detecting the level of formaldehyde in the environment. They may be stationary or portable, allowing the measurements outside the office or working area.

It is not possible in daily life to avoid having formaldehyde and materials containing it, but it is possible and is necessary to monitor the concentration by a formaldehyde meter and to take the measures timely to provide good working and life conditions.

Formaldehyde in the air we breathe is classified as carcinogenic and, in higher concentrations, irritates the eyes and respiratory tract. Formaldehyde is present in large quantities not only in the tobacco smoke, it also evaporates when disinfectants and cosmetics containing formaldehyde are used and can be outgassed over a long period of time from furniture, floor coverings, paints and adhesives, new appliances or even packaging material. A formaldehyde meter helps to detect critical levels before the smell is noticed. Even a simple formaldehyde meter for offices and common rooms usually has a visual or acoustic alarm function for this purpose.

The formaldehyde meter with a data logger function is particularly suitable if the formaldehyde concentration is to be monitored over time. Many versions of the formaldehyde meters are very easy to use and can be carried by those people who frequently work in different areas with substances containing formaldehyde. Other types of devices for workplaces are intended for permanent installation and can transmit the measured values via interfaces to gas warning systems that automatically control the ventilation systems.