FAQ

Gas Viscosity Coefficient

As written in the D.P.C.M. of the 12 March 2002 Title III, art 15 the rule becomes law: This decree enters into force the day of its publication in the Official journal of the Italian Republic. Concerning the time to adapt to the standards, if the machinery is for productive process it has to be adapted within 18 months from the entrance into force of this decree. Concerning the plants for civil use of thermic power equal or more than 1,5 MW installed before this rule became law, they can be adjusted according paragraph 2, within two years from the entrance in law of this decree.

The so called "dangerous" gases are methane, LPG and carbon monoxide and to control them is compulsory. Tecnocontrol produces a detector for each one of the gases listed above.

It means Working pressure

In the same D.P.C.M. of the 12 of March 2002 , Title III art 14 Abrogation it is written : Starting from the date in which this decree became law the Decree of the Premiership 2 October 1995 has been abrogated. Starting from this date the articles 12 and 13 of the law of the 13 July 1966, n.615 have been abrogated according art.2, paragraph 3 of the law of 8 July 1986 n. 349.

Thanks to our calibration kit it will be always possible for our sensor to work accurately. The TC 011 kit (for industrial sensors) and TC 012 (for domestic sensors) will have always to be supported by these articles: Gas cylinder valve BO 301 and gas baloon or an India rubber reserve gas container PA 020.
In addition it will be necessary to be also equipped with a gas cylinder (a gas which matches with the sensor characteristics) in order to run the tests.

It means Test Pressure with Air, expressed in Pascals

The difference is explained in D.P.C.M. of 12 March 2002.
Title I " Fuel and technologic characteristics of combustion plants for industrial use" See art 1 Application field and Art. 5 Plant requisites.
Title II " Fuel and technologic characteristics of combustion plants for civil use" See art 7 .
Essentially the plants for productive process with thermic rated output for single fireplace equal or higher than 6MW have to be equipped with an analyzer to continuously measure and record the free oxygen and the carbon monoxide and with a temperature detector in the confluent gases.
For civil use plants at point 2 art.7 it is specified that they have to be equipped with an analyzer to continuously measure and record free oxygen and carbon monoxide and with a temperature detector in the confluent gases in order to optimize the combustion yield with total thermic rated output equal or higher than 1,5 MW .

Yes, it is. The control unit mentioned above is equipped with a relay. This relay is able to send a pulse which is necessary for both manually or automatic reset solenoid valve to work.

Reference pressure for the test with Gas, expressed in Pascals.

The standard in force concerning the plants for civil use and productive process says that they have to respect the last standards incident to the new D.P.C.M of the 12 March 2002.

You will need a detection central unit SE 230 Km (Methane) or SE 230 Kg (LPG). This central unit could be supported by the SE 296 Km (methane) or SE 296 Kg (Lpg) sensor whether you need to monitor more than one room. This sensor could work together with an unlimited number of equivalent sensors in a number equal to the environments in which they will have to be installed. .

Gas flow dispersed in working conditions expressed in dm3/h (direct method (Gas))

Gas flow dispersed in working conditions expressed in dm3/h (indirect method (Air))

Air flow dispersed in test conditions expressed in dm3/h (indirect method (Air)

(Air)
Leak-finding made with air or gas. To be used only when it is possible to establish the machinery volume and only for plants with volume less than 25 dm3

Leak-finding made with gas at the working pressure

Leak-finding made with air, it lasts 15 minutes, with a pressure that can't be lower than 100mbar. The plant is in compliance if there is no pressure-relieving

This test has to be made closing the valve upstream the meter and doing 2 readings of the meter, one every 15 minutes.

1. There is smell of gas in the setting.
2. Replacemet of the devices using gas.
3. Replacement of the type of gas supplied by the gas station.
4. Reuse of gas plants unused for more than 12 months.
5. At least every 10 years

It is the data according to the regional rule to measure the dry-stone CO (without vapour).

The rule in force doesn't specify which is the best choice, so it is all up to the technician. The main difference between a normally closed valve with manual reset and a normally open one is that the first is "intrinsic safety" that is it can guarantee the gas leakage closing even without electricity and so even when the gas detection system is not working.

It is the temperature at which the humidity contained in the smokes condenses.

It is one of the toxic gases present in the combustion smokes "sulphur dioxide".
It represents the quantity of dioxide in the combustible.

They are the total nitrogen oxides, that is the sum between NO and NO2

It is one of the toxic gases present in the combustions smokes: "nitrogen dioxide"

It is one of the toxic gases present in the combustions smokes: "Nitrogen Oxide".

They represent the difference between the abstract productivity (100%) and real productivity: in other words if the productivity is of the 86%, the leak is of 14%

It is he excess of air present in the smokes. The Ratio, expressed in %, between the difference between the quantity of air used for the combustion and the quantity of stoichiometric air and the stoichiometric quantity itself.

Yes, it is.
How?
If the sensor is stimulated with gas concentrations beyond its limit.
Physical damages

• If the sensors are installed in construction sites not finished yet.
• Solvents and dust might:
• Block up and even close the passage of the air.
• Block up and even close the sensitive membrane.

It is the measuring of smokes opacity made with the bacharach pump

No, you can't!
Why?

• The alarm settings can't be tested
• The sensor is damaged because of the low temperature of the gas emitted and the high concentration you would get.
• Catalytic = 20%LEL
• Pellistor = 100%LEL
• Semiconductor = 20%LEL

To saturate the sensor means that it is no longer able to be sensitive.

The rule number 10 (standard UNI 10389-1) states the formula for the calculation.
Example:
Productivity of a 30.000Kcal boiler installed after 1993:

• at 70°C > 89%
• at 50 °C > 87%

Periodic maintenance is very important.
Maintenance typical periodicity:

• 6 Months = Check / Test
• 12 Months = Calibration

TC011/TC012 Calibration kit

It indicates the vacuum value of the chimney

• Continuous alarms
• Fault warnings
• No alarm or warning (Electrochemical)
• The sensor doesn't detect anythig but it seems like it is normally working

You have to insert the probe in the hole present is in all the vents to an ultimate distance in order to read the highest temperature (in the middle). Generally the smokes temperature during the analysis in of about 120-300°C

It depends on :

• The type of sensor
• The location where it is used
• The gas concentration in the environment.

Electrochemical :1 year (It depends on the type of location and on the gas concentration)
Semiconductor + Catalytic :4/5 years (working)
5/10 years (stored in a warehouse)

With athmosferic boilers what you have to consideri s the setting temperature of the location where the boiler is installed (combustive agent air).
For watertight chamber boilers the temperature probe must be placed in the suction pipe thanks to its threaded cone.

This is the most frequent question asked by who asks information about this kind of products.
But unfortunately the answer is the most difficult to give.
Actually we would expect to have a certain value expressed in cubic or square meters as it happens for smoke sensors.
What we can say is that talking about a gas detector, to decide how many sensors we need to place and consequently, the area covered by each one of them depends on a great number of different conditions which can vary according to the environment in which they have to work::

1. kind of gas
   • flammable
   • toxic
   • heavy
   • light
2. ventilation present in the location
3. kind of emission source
   • tank
   • flange
   • thread
   • gas pressure
4. primer sources presence and position (in case of explosive gases)
5. velocity of the gas spread into the environment

Unfortunately, gas and smokes are two different concepts and they can't be considered in the same way. In fact the smokes sensor detects only one kind of gas: the smoke, precisely. Wherever it comes from, in any way it is produced, the smoke remains always the same substance and for this reason it is easily recognizable. Even from a regulatory point of view, it has been possible to establish the exact number of necessary sensors depending on the installation area. But when we talk about gases, things change: as we have described above, we can have different cases because they depend on the combination of all the aspects described. Generally speaking, in order to accurately interpret a gas environment you need the device of a technician who knows well the rule CEI 60079 in which you can find all the necessary parameters to decide how to precisely build a machinery. Finally there is a non-written rule (but used in a great number of situations) regarding the sensors arrangement in underground parking where it is compulsory to detect carbon oxide and gasoline gases. The detectors are organized in couple (one sensor for carbon oxide and one for gasoline gases) so that they are the centre of circles with a 10 metres radius and the centres are far from each others 16 metres.

If a flammable gas, for exemple methane, burns on the surface of a pellistore, this reaction will cause water and carbon dioxide. They distances from the sensor and they won't cause any damage. Many flammable gases have the same behavior when they burns. But not all flammable gases behave in this way: some of them produce solid substances which sediment on the sensitive element and they cause its gradual covering, while others produce chemical substances which are very corrosive and they damage the sensor. The permanent damage that happens in this case is called " poisoning".
Other gases cause a sensor damage which can be reactivate by exposing it to fresh air: this phenomenon is called "inhibition". Many of the most common cases of industrial poisoning are caused by silicones. When silicon burns it create silicons, whose poisoning originate a strong zero drift and a strong reduction of sensitivity. The most common substances which cause pellistore sensor poisoning and/or inhibition are:

• Silicones
• Sulfured
• Halogens
• Chlorates
• Chlorides
• Fluorides

Unsaturated Hydrocarbons (which contain C=C doble or triple bond)
These last have the effect to polymerize on the sensor, stopping its working. We want to point out that you don't need high concentrations to damage the sensors: they can be poisoned even with a few ppm (part per million). The concentration only determines the damage velocity: the higher is the substance poisoning concentration, the quicker will be the damage to the sensitive element. Since this deterioration is caused by chemical aggressions or by other reasons which always derive from the combustion process, it is better to use, with sensors which detect fammable gases with optical instruments, infrared sensors. They have limits too, but if the gases to be detected belong to their working field and the conditions of the environment are compatible, this is the only solution worth to be adopted.

During the analysis:
10-11% (It depends on the O2 and on the combustible)
in air:
Near to the 0%

During the analysis:
The lowest possible and anyway not higher than 1000ppm
in air:
0 ppm

During the analysis:
from 2 to 5% (Room-sealed boilers) up to 14% (Atmospheric boilers)
in air:
The oxygen in atmosphere is of about 20,9%.

From this perspective, the Ministry states that safety systems must be built and maintained in efficiency according to the technical standards issued by national or international standardization bodies and the instructions provided by the manufacturer and installer. In our case, the devices have a useful life to be respected, after which the sensor or device must be replaced. The detectors also feature a 'self-check' software to signal any anomaly with a yellow FAULT LED. It is important to periodically check the components' status using the test button on each device, which signals alarms optically and acoustically. If an electrovalve is present, it is advisable to also check it periodically.

Each apartment intended for short-term or tourist rental must be equipped with its own safety devices: carbon monoxide and combustible gas detectors and fire extinguishers.

Yes. The regulation applies to individual properties, regardless of the context in which they are located.

Absolutely not. Detectors must be installed by qualified personnel who know the installation standards, can assess the accommodation, and determine the appropriate location and height for the device, ensuring proper installation.

The Ministry does not impose conditions on this. For carbon monoxide models, there is a choice between a battery-powered detector and a 230v-powered version. Methane and LPG devices are only available in the electrically powered version.

The detectors must be installed in such a way that the power supply cannot be easily interrupted, and they should be stably connected to the electrical network. Ideally, if possible, the cables should be embedded.

Yes, methane and LPG detectors have a lifespan of 5 years (for models with a replaceable cartridge, the period is renewed upon replacement), while carbon monoxide detectors have a lifespan of 6 years.

The LPG detector must be placed no more than 30cm from the floor, while methane and carbon monoxide detectors should be placed no more than 30cm from the ceiling. All three should be positioned between 1 and 3 meters from the combustion source. If no sources are present, the carbon monoxide detector should be placed at human height. This should be adjusted to the type of accommodation.

No, landlords of properties without gas installations and where the risk of uncontrolled releases of combustible gases or carbon monoxide formation is excluded are exempt from the obligation to install gas and carbon monoxide detection devices.

No, currently such a product is not mandatory. For safety reasons, however, if possible, it would be advisable to install it to stop the gas supply in case of an alarm.

No, the Ministry has not imposed any conditions on this. Apart from the CE mark (required for product sales), the manufacturer can choose to make the detector compliant with one standard or another.

The devices must be fully functional and emit an optical and acoustic signal in case of dangerous gas detection.

The lessor is required to install a gas detection device based on the type of system (methane or LPG), one for carbon monoxide, and a fire extinguisher.

Yes, the law has been in force since January 1, 2024.

Yes. Even single portions of properties, if rented out under short-term or tourist lease agreements, must meet the safety requirements.

The safety requirements apply to properties where the lease contract involves providing the property without additional services, except for those strictly related to the use of the property (e.g., linen supply, cleaning, etc.).

'Short-term rental' refers to those properties used for short-term lease agreements or leases for tourist purposes not exceeding 30 days, managed either as a business or otherwise, even in cases where the activity was initiated before the actual application of Art. 13-ter of D.L. no. 145/2023.

The decree-law of October 18, 2023, no. 145, converted with amendments by Law No. 191 of December 15, 2023, also known as the 'Short-term rental decree,' regulates rentals for tourist purposes, short-term rentals, and tourist accommodation activities by introducing the national identification code, the national database, but above all, provisions on safety, including the obligation to install devices for detecting combustible gases, carbon monoxide, and fire extinguishers.