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Cooking fumes exhaust systems

The stratifications of organic compounds, in particular of greases, are generated by the fumes of the meals in production which cooling, are going to stratify on the hoods, on the internal surfaces of the ducts, fan included, even if it is far from the fumes origin. These accumulations are the source of bad smells.

A dirty system is destined to lose extraction capacity, allowing to fumes to still remain in kitchens, work environments and hall restaurant. This phenomenon seriously affects the quality of air under all profiles, hygrometry, temperature, etc. Indeed this situation can allow the proliferation and transmission of pathogens (see also Conf. State Regions and Provincial Authorities of Trento and Bolzano no. 1292 dated 27/09/09, 2001 – Protection and health promotions in confined environments, Testo Unico sulla Sicurezza, D.lgs 81/2008, D.M. 12/04/96 – Approvazione della regola tecnica di prevenzione incendi per la progettazione, la costruzione e l’esercizio
degli impianti termici alimentati da combustibili gassosi).

This is owing to either in structural damage or in mechanical dysfunctions of the extraction motor. Over time, the impellers of the extraction fan are unbalanced due to the weight of the greases sedimentations. In some cases the rotor will block due to the breaking of the bearings. We suggest you to not wait for the problem arising, but to try to prevent it by following an appropriate maintenance program.

Greases layers cause two immediate linked effects:

  • Decreased extraction function
  • Percolations of the grease layers in excess, because of temperature changes state.

These layers are fertile ground for the uncontrolled proliferation of micro-organisms, in particular mold and bacteria. The system is near to cooking plans, thus it exposes the whole process of food preparation to a possible contamination (deleting, among other things, the efforts to maintain the qualifications required by the H.A.C.C.P. plans).

Air conditioning and ventilation systems

Indoor environments are the relevant place where it is more easy having proliferation and transmission of numerous pathogens as shown by scientific research (it is also demonstrated we spend about 90% of our day indoors). The pollutants that are detected (such as volatile organic compounds, mineral fibers, microorganisms such as mold and bacteria, carbon monoxide, etc.) are multiple and of a heterogeneous nature. Irritations of the mucous membranes, headaches, colds, influences up to even more serious pathologies (ex .: LEGIONELLA), are all consequences of the attendance of an unhealthy environment. High quality of indoor air and good maintenance of indoor places are strictly collegated. Essentially for this purpose it is important, as well as maintaining a general hygiene, having a good and periodic maintenance of the air ventilation and conditioning systems because of are the main influencers of the air’s features. Especially some times of the year, these systems become a fertile ground for the development, dissemination and contamination of micro-organisms.

Also in this case maintenance is extremely important. Among the pollutants, there are arthropods (mites, arachnids), organic biological material of vegetal birth (pollens introduced by the ambient air) which are airborne through the ventilation system. As the scientific researchs have found, breathing allergen-rich air helps developing relevant diseases such as allergies and asthma.

The layers of pollutants which will accumulate in the internal surfaces of air conditioning system (dust, particulates, molds, bacteria, pollens, etc.) becoming a safety risk to face. The only way to prevent the diffusion of these contaminants, is  keeping the air conditioning system efficient from the point of view of performance, safety and hygiene, realizing a periodic check and remediation. They are the same systems that filter and treat the air which is going to be bring in indoor environments, therefore they must be the first in good hygiene conditions.

The main cause is the formation of particulate layers on the internal surfaces of the ducts system, which over time, will cause a progressive deterioration of the system performance and an increasing risk of ignition and fire conductivity.


Legionella pneumophila is a gram-negative aerobic bacterium, responsible of the disease defined as “legionellosis” or better known as Legionnaire’s disease. We define with  “legionellosis”  all the forms caused by the Legionella genus: it can manifest itself in the form of pneumonia with a mortality rate ranging between 10-15%, in extra-pulmonary feverish form (called “Pontiac Fever”) no fatal or in a subclinical form. The name stems from the fact that the bacterium was first identified in 1976 on a group of participants at an American Legion rally in a Philadelphia hotel; as many as 221 people have been affected by Legionnaire’s disease and 34 of them were died.

Legionella genus includes 61 different species (including subspecies) and about 70 serogroups, but not all have been associated with human disease. Legionella pneumophila is the most frequently detected species in diagnosed cases and is made up of 16 seroproups, of which 1 is the cause of 95% of infections in Europe and 85% worldwide.

The most common symptoms are: high fever, headache, myalgia, chills of cold, cough with frothy red sputum mixed with phlegm. In 10-20% of cases there are also gastrointestinal symptoms such as inappetence, abdominal pain, nausea, vomiting. Diarrhea is very common (25-50% of cases). The possible neurological manifestations (besides the aforementioned headache) are lethargy, encephalopathy, confusional state and alterations of the mental state. This is the historical and more frequent case.

Legionellae are present in natural aquatic environments such as spring waters, including thermal waters, rivers, lakes, muds and artificial ones such as drinking water distribution systems (shower heads, taps), tanks, boilers, sanitary equipment (for instance for therapy inhalation), dehumidifiers and fountains, as well as cooling towers, air conditioning systems and evaporative condensers. They survive at water temperatures of about 20 °C to 50 °C and find nutrients in sediments and organic compounds naturally formed in the aquatic environment (limestone, biofilm). For this reason they are well developed within the water circuits, where water is susceptible to these features.

The risk conditions are those associated with aerosols, most likely in spas and whirlpools, despite this, any condition of use in which the water comes to nebulize is a contagious risk situation, if the bacterium is present. The possibility of acquiring the disease is mainly related to the susceptibility of the exposed subject (predisposing factors, the advanced age, tobacco smoke, the presence of chronic diseases and immunodeficiency) and to the intensity of exposure (virulence, charge infectious bacterial and exposure time). The bacterium if swallowed (not inhaled) does not constitute danger because it is well attacked by the gastro-intestinal flora.

On 7 May 2015, all the indications given in the previous national guidelines and relative regulations were updated and supplemented: “Guidelines for the prevention and check of legionellosis”. As suggested it is necessary to follow a program of use and maintenance calibrated on the specification of each water systems. Among the planned monitoring activities, there are specific technical inspections and sampling, while for the treatment there are different kind of methods. Global Trading has developed an effective intervention in all situations, maintaining an analytical approach but also attentive to the specifics of each individual case, and reducing the possible side effects resulting from other methods of intervention (increase in concentrations of chlorine and its derivatives or similar, deterioration of the invoice material of the ducts and tanks). We also emphasize that although the treatment is born to address the Legionella problem, its efficacy is not exclusive for this bacterium, on the contrary it extends to all the main pathogenic families existing in the aquatic environment. You have to rely on experts in this field.

Slipping Risk Assessment

It is an underestimated theme and actually slipping floors are one of the most frequent and main category of accidents: numerous statistics determine that the slipperiness of the floors causes thousands of very serious and often disabling accidents every year, both in domestic and public environments and also in work environments. From an internal study of the health institute, it is estimated that out of 1,300,000 arrivals to the emergency room in hospitals, 50% is determined by falls

The regulations in force in Italy provide that the floors are maintained with specific friction features which could be measured on site with a specific test. Global Trading follow the standard of this test and specifically we detect the dynamic friction coefficient which is the only value recognized by Italian regulations. If the floor doesn’t comply with the regulations and in the same time it has happened an injury, you risk to be involved from civil to penal liabilities. You could read for references from our page “STANDARDS”: Ministerial Decree 236/89, Decree of the Minister of Public Works 14 June 1989 n. 236 and Legislative Decree 81/2008 Legislative Decree 09 April 2008 n. 81.