## 3 Materials and Methods
### Server Architecture
#### 3.3.2 Web Application: Exposure Data and Alerts  
Based on the health information supplied when registering a worker, the web application will automatically define attention points (exposures with which greater care should be taken). The rules for this purpose consider the columns \"Agents\", \"Pre-diagnosed diseases\", and \"Symptoms\". The agents correlating with all of the pre-diagnosed diseases and symptoms are considered to generate alerts along with the total time worked in other companies in similar positions. The health data provided during employee registration can be updated by the employer at any time. The alerts are shown on the web page \"Exposure data and alerts\" and the general format of an alert is as follows:  
\"In respect to diseases and symptoms, this person has: disease 1, disease 2, disease  n. Due to reported diseases and symptoms, it is advised to avoid or reduce exposure to the following agents: agent 1, agent 2, agent n. Including other companies, the worker has performed activities of the same type and has been exposed to the same agents for n years. Attention to health is recommended.\"  
Examples are given below:  
1. When registering a worker who has been diagnosed with a single disease, e.g., asthma, all of the agents related to asthma in Table 2 (cold, dust, and high and low humidity) are considered to generate an alert. 2. When registering a worker who has been diagnosed with two diseases, each correlating with a different agent, e.g., dust and noise, an alert considering both agents is presented. 3. When registering a worker who reports that he or she was not diagnosed with any of the diseases listed but mentions at least one symptom that may be caused or worsened by the exposure to one agent, e.g., cold, an alert related to cold is shown. 4. When updating the records of a worker who was diagnosed with a disease correlating with a single agent but currently mentions a symptom correlating with another agent, an alert considering both agents is shown. 5. If a worker does not present symptoms or diseases, the system does not generate alerts. \begin{table}
\begin{tabular}{c c c c} \hline
**Agents** & **Pre-Diagnosed Diseases** & **Related Occupational Diseases** & **Symptons** \\ \hline \multirow{6}{*}{Cold [60, 61, 62, 63, 64, 65]} & Asthma & & Chest pain \\  & Hypertension & & (Cough) \\  & Hepatitis diseases & & (Dypense differences of breath) \\  & Spinal disorders & & (Hedarde) \\  & Respiratory diseases & Increase in musculoskeletal disorders & Hemoptiys (blood cough) \\  & & Respiratory diseases & Skin lesions \\  & Previous allergic diseases and reactions & & (Night rash) \\  & & & (Neck, lower back pain, and joint pain \\ \hline \multirow{6}{*}{Dust [61, 64, 65]} & Asthma & Chest pain \\  & Lung cancer & Pulmonary fibrosis (abstenosis) & (Cough) \\  & Lung diseases & Lung cancer (due to inhalation of asbestos dust) & (Kerv) \\  & Previous tuberculosis & & (Hedarde) \\  & Smoker & & (Night loss) \\ \hline \multirow{6}{*}{Heat [66, 67]} & Diabetes & Dehydration (lavors the occurrence of kidney problems) & Chest pain \\  & Heart disease & Heart attack & (Failing (syncope) \\  & Hypertension & Stroke & Headache \\  & Hypotension & Dynes of the nasal mucosa (lavors the emergence of & Increased third \\  & Kidney disease & respiratory infections) & Increased urinary volume \\  & & & (Wight loss \\ \hline \multirow{6}{*}{High humidity [61, 68, 69]} & Asthma & & Chest pain \\  & Diabetes & & Dynes (documents of breath) \\  & Respiratory diseases & & Hemoptiys (blood cough) \\  & Previous allergic diseases and reactions & & Increased third \\  & & & (Wight loss) \\ \hline \multirow{6}{*}{Low humidity [69, 70, 71]} & Asthma & & Chest pain \\  & Respiratory diseases & & (Cough) \\  & Previous allergic diseases and reactions & & Dynes (documents of breath) \\  & & & Hemoptiys (blood cough) \\  & & & Skin lesions \\  & & & Skin rash \\ \hline \end{tabular}
\end{table} 
Table 2: Agents, diseases, symptoms, and their correlations.