Chemical agents are products or substances that can enter the organism through the respiratory tract, in the form of dust, fumes, mists, mists, gases or vapors, or that, may have contact or be absorbed by the organism through the skin or by ingestion.
Effects on the human organism
After entering the body, chemical agents can cause a variety of toxic effects, including immediate (acute) or long-term (chronic) effects, depending on the nature of the chemical and the route of exposure.
The most affected parts of the body are the lungs, skin, nervous system (brain and nerves), bone marrow, liver and kidneys.
Chemical Risks Classification of effects: Irritating and / or corrosive: cause changes in the skin or mucous membranes (cement, acids, bases); Sensitizers: produce allergies (nickel, chromium, synthetic fibers); Asphyxiants: prevent the organism from obtaining or using oxygen from atmospheric air (carbon monoxide (CO), cyanides); Narcotics: produce unconsciousness (chloroform, ethers, alcohols, acetones); Neurotoxic: produce changes in the nervous system (aniline, lead, mercury, benzene, solvents in general); Carcinogens: produce malignant tumors (asbestos, benzene, cadmium, chromium); Mutagens: produce hereditary problems (glycol ethers, lead, benzene); Teratogenic: produce malformations in the fetus (radioactive substances).
Main chemical risks with welding
The risks associated with different welding processes and coated materials.
Serious illnesses related to exposure to various types of solder fumes
include the following:
- Cancer of the lungs, intestines, liver;
- Damage to the brain;
- Neurological diseases;
- Reduced lung capacity;
- Skin diseases;
- Fertility problems.
In welding processes there is a fusion, joining of two metals due to high temperature heating. In such cases, aerodispersoids, called metallic fumes, are generated due to the thermal process followed by oxidation. This occurs in the following way: the metal, until then solid, goes into a liquid state, a part is volatized and then solidified when it meets the air at a lower temperature. From there, small particles are formed that are in the respirable fraction. Such particles can enter the respiratory system and settle in the alveoli, in the gas exchange region.
Recently, AIPC, the International Agency for Research on Cancer, classified metal fumes in general as proven carcinogenic. Probably, part of this comes from the carcinogenicity of metals such as: chromium, nickel and cobalt. In addition to these, there are studies that indicate iron oxide as a carcinogen, which is quite worrying since it is present in the vast majority of metallic materials.
Due to this classification of fumes as carcinogenic, the recommendation is that all metals present in metal fumes should be treated as a mixture, that is, the sum of the ratios between the concentration and the limit of each metal should be less than 1.
Whenever potential health risks are identified, the necessary and sufficient measures must be taken to eliminate, minimize or control chemical risks in the work environment.
Recognition of risks in welding processes
To make a correct recognition of risks in welding processes, one must take into account which consumables are present in the environment: gases, electrodes, welding rods, dispersion factors (ventilation system, open environment, semi-open environment) , information specific to that process, the base metal, flow material and the other processes involved: cutting, sanding.
To avoid problems related to metal fumes, the use of respiratory masks is always recommended. It is possible to obtain a good and safe work environment, reducing the number of sick leave and preventing premature retirement.
A good working environment means that the final product will be superior and productivity will be higher. A safe working environment needs safe and decent working conditions. Exhaust at the source is the most efficient method for collecting and removing solder fumes.
Ergonomics or human engineering is a relatively recent science that studies the relationship between man and his work environment and defined by the International Labor Organization – ILO as “The application of human biological sciences together with the resources and techniques of engineering to achieve the mutual adjustment, ideal between man and his work, and the results of which are measured in terms of human efficiency and well-being at work “.
Ergonomic risks are the factors that can affect the physical or mental integrity of the worker, providing him with discomfort or illness. Ergonomic risks are considered: physical effort, weight lifting, inadequate posture, rigid productivity control, stressful situations, night work, prolonged working hours, monotony and repetition, imposition of intense routine.
Ergonomic risks can generate psychological and physiological disorders and cause serious damage to the health of the worker because they produce changes in the body and emotional state, compromising their productivity, health and safety, such as:
RSI / WRMD, physical tiredness, muscle pain, high blood pressure, sleep disorders, diabetes, nervous disorders, tachycardia, digestive tract diseases (gastritis and ulcers), tension, anxiety, back problems.
In order to avoid that these risks compromise the activities and the worker’s health, an adjustment is necessary between the working conditions and the man under the aspects of practicality, physical and psychological comfort through: improvement in the work process, better conditions at the place of work, modernization of machinery and equipment, improvement in the relationship between people, change in the rhythm of work, appropriate tools, proper posture, stretching.