FAQ
What are the gases you need to check on in a domestic environment or in a thermal power station?
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.
How do we periodically calibrate our sensors?
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.
Is the domestic control unit model SE 230 KM (Methane) or SE 230 KG (Lpg) able to control a safety electrovalve?
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.
If I want to make a detection methane or Lpg plant in a domestic environment, what articles do I need?
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. .
In a gas detection plant is it better to install a safety electrovalve normally open or normally closed?
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.
Is it possible for the sensitive element to be damaged?
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.
Can I test the sensor with any kind of gas? (gas-lighter)?
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.
Does the sensor need periodic maintenance or calibration?
Periodic maintenance is very important.
Maintenance typical periodicity:
- 6 Months = Check / Test
- 12 Months = Calibration
TC011/TC012 Calibration kit
What does happen at the end of a sensor life?
- Continuous alarms
- Fault warnings
- No alarm or warning (Electrochemical)
- The sensor doesn't detect anythig but it seems like it is normally working
How long does a sensor life last?
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)
How large is the area that can be covered by a gas sensor?
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::
- kind of gas
- flammable
- toxic
- heavy
- light
- ventilation present in the location
- kind of emission source
- tank
- flange
- thread
- gas pressure
- primer sources presence and position (in case of explosive gases)
- 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.
How a sensor can be damaged by polluting or inibiting substances?
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.
Do these products require maintenance?
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.
I rent several apartments in the same building; how many fire extinguishers and detectors do I need to install?
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.
The building where the apartment I rent is located is already equipped with compliant fire extinguishers and gas detectors. Do I need to install them inside the apartment as well?
Yes. The regulation applies to individual properties, regardless of the context in which they are located.
Can I install the devices independently?
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.
So I can't install a battery-powered detector?
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.
How should the connections be made?
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.
Do the detectors have a useful life to respect?
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.
Where in the property should the detectors be placed?
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.
If my apartment is gas-free, am I required to follow this law?
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.
Is the installation of an electrovalve mandatory?
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.
Do the devices need to comply with specific standards?
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.
Do these devices need to have specific features?
The devices must be fully functional and emit an optical and acoustic signal in case of dangerous gas detection.
What products must I install to comply with the law?
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.
Is the law already in force?
Yes, the law has been in force since January 1, 2024.
I rent out a single room of the property, do I need to meet the safety requirements?
Yes. Even single portions of properties, if rented out under short-term or tourist lease agreements, must meet the safety requirements.
Which specific premises must comply with this Law?
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.).
What is meant by 'short-term rental,' and who must meet the safety requirements?
'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.
What does Law No. 191 of December 15, 2023, provide?
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.