During the sampling process, strict adherence to occupational health and safety regulations was ensured to guarantee the safety of both plant employees and sample collection personnel. The main risks that may be encountered in biogas plants include flammable gases (methane, hydrogen sulfide), pressurized equipment, and biological materials. To mitigate these risks, personal protective equipment (PPE) was provided prior to sampling; chemical-resistant gloves, safety glasses, and work shoes were used.