Noise and vibration-free surroundings are essential to our guests' comfort and satisfaction and therefore we develop projects to reduce this bothersome type of pollution.

Often the terms noise and sound are used indistinctly, because the difference between the two is rather subjective.

Sound can be defined as "any variation of pressure detectable by the human ear ", whereas a simplified definition of noise would be "all undesirable sound".

One example of a noise reduction project is being developed in Puerto Plata (Dominican Republic), where the energy production plant generator has been replaced.

Below is a very brief summary of the successive stages carried out to prevent noise emission and the propagation of vibrations:

1. Replacing the existing generators

Existing generators have been replaced by others with the most cutting-edge technology, in other words, the most modern, powerful and best performing generators. Replacing the existing machinery with quieter machinery is the first option (and almost always the most effective) for decreasing the noise level in a certain zone.

2. Choosing the most appropriate site for generators

Generators have been installed in the resort zone farthest from guests' rooms to keep the source of noise as far from people as possible.

3. Isolating the source of noise

In order to isolate the source of noise, each generator was placed inside a special container designed to prevent a large part of the noise they generate from reaching the outside. These types of containers cannot be totally watertight since openings for ventilation, operations maintenance, etc., are needed. In any case, the size and number of openings were kept to an absolute minimum.

4. Using absorbent coating on wall facings

In this project, noise-absorbent facings (made of porous materials) have been used on walls and ceilings in industrial naves where generators are housed. These absorbent coverings' effectiveness is manifest only at a certain distance from the noise source, which once again demonstrates that the location of generators in the zone farthest away from guests is a sound decision.

5. Building a soundproof enclosure in the nave for maintenance personnel

Since there are employees who must remain in the zone right at the entrance to the plant carrying out maintenance and monitoring work, a soundproof enclosure was constructed inside where they stay during most of the working day. Individual protective gear such as soundproof helmets and protectors has been placed next to the entrances or exits of the soundproof enclosure, to be used by employees whenever they leave it.

6. Using absorbent barriers outside industrial plants

The goal of absorbent barriers is to limit the range of noise transmission. Furthermore, factors such as the barriers' height and relative position of the source and /or listener are decisive in the levels of noise reduction that can be achieved.

7. Using techniques to reduce vibrations

Care was taken throughout all the work phases in the construction of industrial plants that would house generators to prevent the transmission of vibrations from the generators to a plant's structure and in turn, to guest zones.

The most appropriate isolation techniques were used in each case to prevent any vibration transmission problems: generators were placed on cushioned supports, the most suitable foundations were used for the special containers that house the generators, vibration shock absorbers were placed in critical structures, such as chimneys, elevated walkways, etc..

Experts from the Group's installation firm collaborated in this phase.

8. Establishing a maintenance programme

In most cases, the amount of noise a machine in operation emits varies according to how well it has been maintained. RIU has a preventive maintenance programme devised to reduce noise emission that states in detail the parts of generators that should be monitored especially closely, among other aspects.

Measurements were taken and are being used as a benchmark for machines' noise levels in ideal conditions. The idea is to compare the noise level at a certain time with the one obtained in optimal conditions and ensure that the difference between the two does not exceed 2 dB(A).

Naturally, like any machine, the generators installed have a useful life beyond which replacement is inevitable.