The evolution of the law and the rules governing the pool from the building use and its management have helped to diversify the supply of components in order to make pool for community use safer and more comfortable. The
broad consensus that water parks are having throughout the country, the tourism center and swimming pools installed in health clubs and fitness facilities are a further confirmation of what is necessary to have equipment capable of ensuring user safety and comfort.
So, in 1997, the UNI 10637 standard that, with subsequent revisions and additions, traces the guidelines for the design of filtration, circulation and recirculation of swimming pools in general. The standard wants to continue the effort of the provinces of Trento and Bolzano in 1991 they laid the first version of the act of understanding between state and regions that are suspended in 1993. In 2003 he published revision of the act of understanding between State and Regions, which calls on regions to implement the act individually and make a regional law on swimming pools. In 2006 he published the standard UNI 10637 which inspired almost all the regions that today have a specific law for the pools. Currently, not all regions have made the Italian law on swimming pools, but still make it. For this reason, in the case of the construction of a plant for a swimming pool for public use in a region where there is no law, it is advisable to follow the UNI 10637.
In brief summary that you will find here, we're going to identify the parts which relate mainly to the sizing of the filtration and circulation depending on the type of pool and greatness. For other issues please refer to the requirements of that standard.
Classification of pools The first point to be defined in order to start the calculation of the system, is the type of pool is required of us. The pools are divided into four types, each of which may have the categories.
Type swimming pools open to the public or to a user identified with or without the payment of the ticket.
Category A1: public swimming pools, such as communal.
Category A2: collective use swimming pools, set in structures used primarily for accommodation or other activities at the public (hotels, cottages, camps, gyms, schools, barracks, etc.)..
Category A3 pools for the water games.
Type B: common swimming pools are designed for use only by residents of the apartment building and their guests, excluding condominiums up to 4 units.
Type C swimming pools for use by rehabilitation and healing, placed in preliminary structures.
Type D: Swimming in the service of single-family housing units, semidetached, three-family and four-family.
Water Requirements
The water supply requirements must be in conformity with existing legislation on water for human consumption for all types of pools (freshwater). The water input, that is water filtered and treated by the plant must have the chemical and physical characteristics set out in Table 5.1.2. The water bath, ie the water in the pool, must be in accordance with the requirements in Table A of the State-region in 2003. The water in the overflow tank is not subject to this requirement because it has to be treated by the plant.
sampling points for health checks For pools of type A, B and C, the water must be taken from a special tap on the supply pipes for water supply, while water entering the water must be drawn from a special tap placed on the feed pipe, downstream of chemical treatments and near entry into the tank.
For pools of type D is recommended for this requirement.
The frequency of sampling is defined in Table 2 in paragraph 5.1.7.2.1 and later.
plant movement The system shall be designed to ensure an effective homogenization of the water tank. The velocity of the water
must be ≤ 1.7 m / sec. intake, except for the section connecting the pump to the collector, ≤ 2.5 m / sec. delivery, except for the section connecting the pump to the collector. The hoses in the pool A and B should be sized so as to have losses of ≤ 40 mm / m for the intake and 70 mm / m for the delivery. We accept short sections of pipe and pressure drop over, they do not affect the final performance of the system.
The release of water in the tank walls that can be done either by the fund, provided it is ensured homogenization of the water.
Systems recovery artificial
1) overflow gutter: The overflow gutter shall extend to the rectangular tanks at least on the long sides and the free forms at least 60% of the external perimeter of the tank. The entire development of the overflow gutter shall have a maximum level difference of 2 mm. The overflow gutter and hoses for the unit of time must be disposed of without the water overflowing the input, the maximum volume displaced by bathers in the bath, the volume of the wave generated by the swimmers themselves.
2) skimmer: the use of skimmers is only allowed in the pools of type A2 having an area ≤ 100 m in number at least one skimmer for every 20 square meters, swimming pools TPO ≤ B with an area 150 square meters, of which there at least one skimmer for every 35 square meters in all pools of type D, where a skimmer is recommended at least every 35 square meters.
The skimmers must be placed with a mutual difference of maximum level of + / - 1.5 mm.
System Recovery immersed immersed recovery systems must be installed to prevent the risk of being sucked, so they must be installed in pairs at a minimum distance of 2 m on a single pipe to be connected to the intake manifold plant.
Compensation water
The volume of the conventional overflow tank should be sufficient to maintain the maximum number of bathers present in the bath, the volume on the possible wave generated by the swimmers themselves, the volume generated by backwashing at least one filter, the volume necessary to maintain the proper intake and avoid dry running. The overflow tank should be emptied completely, accessible to staff in respect of safety standards, with overflow and covered with washable material.
system level management of the compensation tank should enable the reintegration before reaching the minimum level to avoid the stand-by pumps up to the level of travel.
water supply system restoration and renewal. The pools overflow on board of any type and pools skimmers type A2 and B must be equipped with automatic refilling system / facility renewal and overflow. On the system of restoration and renovation of pools A and B must be installed a meter to check the volume of water actually placed.
requirements of filtration systems
filter systems must be designed so as to ensure a long circulation of less than or equal to that of the following table:
CLASSIFICATION OF POOLS
| Type
bath | Pools
public
A1 | Pools
use
collective A2 |
Pools for the game
aquatic A3 | Pools
Monthly
B | Pools
within health care facilities or rehabilitation
C |
pools in residential buildings
from mono to four-family
D |
| Baths swimmer and training to swimming depth ≤ 1,200 mm | 3 | 3 | - | - | - | - |
| tanks and training swimmers to swim with a depth> 1,200 mm | 4 | 4 | - | - | - | - |
| tanks for diving and underwater activities | 6 | 6 | - | - | - | - |
| Baths recreational depth ≤ 600 mm (*) | 1 | 1 | 1 | 2 | - | 4 |
| Baths recreational depth> 600 mm (*) | 2 | 2 | 2 | 3 | - | 6 |
| Baths recreational depth> 1200 mm (*) | 3 | 3 | 3 | 4 | - | 6 |
| children's pool with a depth ≤ 400 mm (*) | 0.5 | O, 5 | 0.5 | 0.5 | - | - |
| children's pool with a depth> 400 mm \u0026lt;600 mm | 1 | 1 | 1 | 2 | - | - |
| tanks for use in rehabilitation | - | - | - | - | - (#) | - |
| wave pool | - | - | 2 | - | - | - |
| area ditching slides | - | - | 1 | 3 | - | - |
| Rivers / ≤ 800 mm deep streams | - | - | 1 | - | - | - |
| Rivers / streams with depths> 800 mm | - | - | 2 | - | - | - |
( *) to identify the type of tank, refer to the prevalent as indicated by the management protocol and self-control
(#) parameter be given in the design, in relation to the determination of use of the system and the type of users.
recirculation times shown are maximum values \u200b\u200brefer to experiences with peak frequency of 1 every 3 cubic meters of wetting the surface of the pool. These times should be reduced in the case of swimming against swimmers as large areas of massage. In the case of multi-purpose tanks or with different depths, the capacity is calculated by adding the volume of each area of \u200b\u200btank with different uses a proportional percentage of the volume of conventional overflow tank, used for any volume of circulation time as the above table . The result will be calculated as the sum of the flows. If there are several types of use in the same tank, the system must be calculated by using the time filtering lower. In the case of a single system to serve more tanks, each must be respected recirculation time required by the table above.
Prefilters In the case of type A pools, pre-filters must be ≥ 2, installed in parallel, inspected and basket can also operate with 25% of obstruction of water flow.
pumps circulation pumps must ensure the design flow rate of the system taking into account the pressure drop of 50% generated by the filter needs backwashing. In pools A and B pumps must be equal in number to those of the filters must be installed and a pump additional reserves subservient to each filter. Each pump shall be equipped with: valve inlet and outlet, pressure outlet, if necessary check valve on outlet.
Filters Filters are made of shells whose inner surface has to be adapted to treat water and disinfectant. They must have a label which contains: the pressure test, which must be ≥ 1.5 times the maximum working pressure with a minimum of 350 kpa, the pressure, the surface of filtration, filtration rate for design conditions, the characteristics of the filter elements and the nominal pressure drop at maximum operating conditions.
For pools of type A, there must be a number of ≥ 2 filters and filters installed on the same system must have the same characteristics. For
pools B and C, we recommend the installation of two or more filters.
Features respect to the characteristics and type of use, sand filters must have the following characteristics:
| sand filters for swimming pools:
Type A Ø ≤ 500 ≤ 1,000 mm
Type B and C with a diameter of ≤ 1,000 mm Type D
| sand filters for swimming pools:
type A, B and C with Ø> 1.000 mm |
| can be equipped with any system of internal distribution that would ensure a uniform flow and that it affects the whole of the filter. If you have not provided a suitable support (eg a plate) the media filter should be supported by an appropriate layer of grit on the bottom of the filter and top up to cover the filtered water system. | must have the support of the filter carrying the camera system |
addition, pools of type A may not be used in filters with a diameter less than 500 mm, have an opening adapted to routine maintenance, a drain and a vent tube.
sand filters monolayer Sand filters must have a single-layer filter bed of sand particle size from 0.4 to 0.8 mm may be supported by a layer of grit. The minimum height above the sand layer grit or water recovery system shall be as shown in the following table:
|
| Filtered ≤ 1,000 mm
pool type A, B or C ; | filters with a diameter of ≤ 1,000 mm
pool D | filters with a diameter of ≥ 1,000 mm
for all types of pools |
| Minimum height of the filtering layer in mm | 600 | 400 | 800 |
The filtration rate shall instead comply with the following table:
| Type A | Type B Type C | | Type D |
| ≤ 35 cm / h | ≤ 40 cm / h | ≤ 40 cm / h | ≤ 50 cm / h |
The filter cleaning should be done by reversing the flow regime and the flow rate must be such to put into the flotation element.
Water from backwashing is rinsed and the possible waste water.
filters diatoms diatom filters must be equipped with rigid or flexible coated fabric on which is done by depositing a layer of diatomaceous earth (diatoms) which is the filter surface. The replacement of diatoms should be done periodically in order to ensure continuous smooth operation of the filter. The difference in pressure between the clean filter and the regeneration is 0.7 bar. The regeneration of water containing diatom exhausted should be considered wastewater. The maximum rate of filtration must be ≤ 10 cm / h. on these filters do not allow flocculation.
disinfecting facilities
Each pool must have a filtration system is dedicated to it. For pools A and B, you use the substances referred to by the State-region, namely:
liquid chlorine (liquefied clorogas)
sodium hypochlorite Calcium hypochlorite
anhydrous sodium dichloroisocyanurate sodium dichloroisocyanurate dihydrate
TCCA
ozone
To return the value of chlorine to the water requirements of the tub after a shock treatment is allowed in the absence of wetting, the use of thiosulfate or sulfite / sodium bisulfite.
Batching plant with chlorine During periods open to the public swimming pools of type A, B and C do not allow the direct entry points into the tank or accessible to users (skimmers, overflow channel edge) of substances containing chlorine. The release must be made only by the installation of movement through plants automatic or manual dosing. Moreover, such facilities must be interlocked with the circulation system to prevent free movement of product entries. The direct entry in the tub is allowed only in the absence of swimmers (shock treatment) and bathing can be resumed only when the values \u200b\u200bof the chlorine will be back to normal. The chlorine-based solutions for the pumps must be contained in tanks and have a suitable basis for a period greater than or equal to 24h. Furthermore, storage must be equipped with safety devices (double wall tanks, containment). For pools of type A, B and C equipment and tanks shall be allocated in a separated from the local filtration. If this is not possible, appropriate measures must be taken to prevent the spillage of the tank traps el'innesco. The containers must be labeled content. In pools of type A should be adopted systems of automatic control of the assay. The same rules apply also to control the pH in the Products permitted for its correction are:
to raising the pH: sodium hydroxide solution / sodium bicarbonate
for lowering pH : sodium bisulfate / hydrochloric acid / sulfuric acid.
The pH correctors shall conform to the rules technical regulations.
measuring equipment and control equipment for measuring and adjusting the pH must have an output signal to drive the batching plants.
For pools of type A is preferred proportional control and is recommended automatic recording of measured values.
equipment for measuring the redox potential can be used in pools of type A, B and C in order to monitor the evolution of organic pollution of the water tank and to drive the metering equipment, but must also be adopted systems readings of chlorine, to verify the operation of equipment. The use of redox systems to extrapolate values \u200b\u200bof chlorine and other disinfectants are not allowed.
water Renewal The renewal of the pool must be at least 5% of the volume of the pool plus the 60% of the conventional overflow tank. If the figure of 30 liters per bather per day made up for periods of time homogeneous and representative deviate much from the value of 5%, the operator may decide that a reduction in any case can not go below 2.5% of the volume of the pool plus the 60% of the conventional overflow tank. The renewal of water daily can be suspended during periods of closure plant to the public for closing times to 24 hours.
management requirements must be delivered to the client system running a report by the installer before using or opening to the public system. It must also be given a description of the system, including types and design specifications, functional diagram and technical documentation.
plants must contain a functional identification by labeling that allows the safe management of the same. For the systems of type A, B and C must be displayed inside the building a functional diagram pointing to the aforesaid identification.
