LOSS PREVENTION

Plant Inspection in Hazardous (Classified) Areas

Any plant must be inspected before its first start-up. This service can be done by the operating company or by some external company. Initial inspections must be comprehensive and are intended to check out whether the existing type of protection is according to project specification.

To ensure that the facilities are maintained under satisfactory conditions, periodic inspections or continuous supervision by qualified personnel are required, and where needed, maintenance should be provided. Periodic inspections are conducted in a routine basis. They can be visual, close or detailed. The type of equipment, manufacturer guidance, deterioration, zone of use and previous inspections results determine the level and the interval of periodic inspections. The periodic inspections interval should not exceed 3 years without an expert opinion. Mobile electrical equipment are more susceptible to damage or misuse, and therefore, the inspections interval should be established in agreement.

Sample inspections may be visual, close or detailed. The size and composition of all samples depend on the inspection purpose.

Continuous supervision is based on the presence, inspection, assistance, caution and frequent maintenance of the electrical installation. The qualified personnel must have experience in a specific installation and its environment, in order to keep the explosion protection characteristics under satisfactory conditions. Where the facilities have no chance of continuous supervision, they will be subjected to periodic inspection.

Visual inspections allow us to identify those defects that are apparent at sight; for example, missing bolts, open equipment, broken enclosures, etc. This type of inspection does not require the use of hand tools, ladders or other access devices.

Close inspections allow us to identify those aspects covered by visual inspection and, in addition, to identify those defects that are apparent only by means of tools and access devices; for example, loose bolts. Close inspections do not normally require the enclosure to be open or the equipment to be de-energized.

Detailed inspections include those aspects covered by close inspection and, in addition, identify those defects that are apparent only by opening the equipment and/or using tools and testing appliances (e.g.: to loose connections). Thus, this method of inspection requires the equipment or the plant to be de-energized.

Establishing an adequate timing between inspections is not easy, but it shall take in account the deterioration grade expected for such equipment. The main factors that can affect the equipment deterioration include: corrosion, exposure to solvents and other products, dust or dirt accumulation, water ingress, exposure to excessive ambient temperatures, mechanical damage risk, exposure to undue vibrations, training and personnel experience, unauthorized modifications or adjustments, inappropriate maintenance (e.g.: lack of compliance with the manufacturer recommendations). Once the time between inspections was established, the plant may be subjected to sample inspections aiming to prove or modify the proposed intervals or the inspection grades.