Ventilation in industrial buildings
One of the main problems faced by an industrial building owner is to maintain adequate ventilation in his industrial warehouse. There is a lot of ignorance about this matter and many clients end up spending a large amount of money on systems that are not entirely efficient, or that simply aren’t the most suitable for that building. For this reason we want to shed some light on this matter in order to facilitate the decision, clarifying the current regulations, what options exist, and what are the advantages and disadvantages of each ventilation system in industrial buildings.
Spanish regulations for ventilation in industrial buildings
In Spain there are laws that regulate the climatic conditions that must be applied in the workplace. Here we list and explain those applicable to our case: the ventilation of industrial buildings.
- Anexo III del BOE-A-1997-8669: In this Royal Decree, the conditions of temperature, humidity and air speed in different work environments are stipulated. Given that manufacturing and logistics works are usually done in industrial buildings, we are going to apply the values relative to light activities.
- Temperature must be between 14Cº and 25ºC.
- Humidity must be between 30% and 70%.
- Employees shouldn’t be exposed frequently or continuously to speeds greater than 0.75 m/s in non-sedentary jobs in hot environments. This speed will be lower for fresh environments ans sedentary works.
- Disposición 19915 del BOE núm. 298 de 2009: Here it is regulated that in public places and work spaces the air conditioning set temperature cannot be below 26ºC.
- Real Decreto 1027/2007: It is indicated that the minimum air renewal in commercial buildings should be 8 cubic decimeters per second per person.
Taking into account all these margins that the law marks us, we are going to look for what would be the means at our disposal to ventilate an industrial warehouse.
Tpes of ventilation in industrial buildings
There are several ways to ventilate any building. The fundamental principle on which air circulation is based is pressure differences. These can be achieved naturally by taking advantage of weather conditions or by mechanical systems that force these pressure differences. Here we list some and explain how they work.
Are the most economic ventilation systems that exist.
By generating strategically placed openings in the building, it is possible to ensure air circulation and is renewed by the action of the wind or physical forces.
- Crossed: With overtures in opposite walls from the building, natural air currents are generated, improving comfort and renewing the air in the room.
- Natural inducida: Hot air is lighter than cold air so it tends to accumulate in the upper layers of the building. To take advantage of this phenomenon, through openings in the lower areas of the building and on the roof, the air is renewed. The hottest air escapes through the upper openings, making room for outside air to enter through the lower openings.
The main advantage of thies systems is that they are more economic because they don’t involve an extra expense. However, they are difficult to control because they are at mercy of the weather conditions and can be insufficient.
Mechanical ventilation is that which is achieved through the artificial generation of air pressures in the environment.
- Overpressure: A positive pressure is created with fans that introduces air into the building and comes out naturally through windows, doors and vents.
- Depression: A negative pressure is generated with fans that extracts the air from the building, leaving space for new air to enter through windows and vents. The Airwall fan is an efficient example of this.
- Ambiental or general: This kind of ventilation is one that seeks to circulate the air throughout the room before leaving.
- Located: If there is a source of air pollution, this air can be extracted using hoods and thus prevent it from circulating throughout the entire space of the building.
Ventilation solutions in industrial buildings
Knowing what limits we can reach and what resources we have to ventilate a building, we are going to see some of the applications that ventilation has.
Although ventilation systems cannot reduce or increase air temperature, they can improve the well-being of the workers in our industrial building, and consequently their productivity. The moving air manages to improve the thermal sensation depending on its speed, as can be seen in the following graph.
As can be seen in the diagram, if a building is at 27ºC in a humid environment, if we manage to move the air at a speed of 0.75 m / s (maximum allowed continuously) we would achieve a thermal sensation of 24.5ºC.
To ventilate a whole building maintaining an optimal level of comfort we recommend any of our HVLS models. This fans aren’t just a magnificient option of general ventilation, but their long blades allow large quantities of air to be moved at very low revolutions, so the energy savings are really noticeable compared to other ventilation systems. They allow to adjust its speed and activate the reverse mode.In an industral building is really usefull this last mode because all the heat generated that accumulates on the roof of the warehouse is distributed throughout the room, achieving a homogeneous temperature and that heat reaches the ground level.
if humidity levels ar too high, installins a depression ventilation system which evacuates environment humidity would be the optimal solution. From Magnovent, we recommend our HVLS fans in combination with vents. This fans have a large life in high humidity conditions due to its IP65 protection.
HVLS fans also have applications in some production processes. There are products such as food or liquids that undergo drying processes. The air our fans generate allows to accelerate this processes increasing productivity.
On the other hand, just as they improve the comfort of human beings, farm animals also benefit from this thermal comfort. Maintaining the optimal temperature for livestock on farms, it reduces their stress and thus improves their milk or egg productivity.