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GB/T 16895.19-2017 (GB/T16895.19-2017)

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GB/T 16895.19-2017
Low-voltage electrical installations. Part 7-702. Requirements for special installations or locations. Swimming pools and fountains
ICS 91.140.50
Q77
National Standards of People's Republic of China
Replace GB/T 16895.19-2002
Low voltage electrical installation
Section 7-702. Requirements for special installations or locations
Swimming pool and fountain
Part 7-702. Requirementsforspecialinstalationsorlocations-
(IEC 60364-7-702.2010, IDT)
2017-07-31 released.2018-02-01 implementation
General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
China National Standardization Administration issued
Content
Foreword III
Introduction IV
702 swimming pool and fountain 1
702.1 Scope 1
702.2 Normative references 1
702.3 Terms and Definitions 1
702.30 Assessment of general characteristics 2
702.30.101 General 2
702.30.102 Description of Zone 0 2
702.30.103 Description of Zone 1 2
702.30.104 Description of Zone 2
702.4 Security 3
702.41 Electric shock protection 3
702.410.3 General requirements 3
702.410.3.101 Special requirements for each zone 3
702.414 Protection mode. Safety Extra Low Voltage (SELV) and Protection Extra Low Voltage (PELV) 4
702.414.4 Requirements for SELV and PELV circuits 4
702.415 Additional protection 4
702.415.2 Additional protection. auxiliary protection equipotential bonding 4
702.5 Selection and installation of electrical equipment 4
702.51 General Rule 4
702.512 Conditions of use and external influences 4
702.512.2 External influence 4
702.52 wiring system 5
702.522 Selection and installation principles related to external influences 5
702.522.8 Other mechanical stresses 5
702.522.8.101 Installation method determined by region category 5
702.522.8.102 Restrictions on the cabling system by region category 5
702.522.8.103 Additional requirements for fountain wiring 5
702.522.8.104 junction box 5
702.53 Switchgear and control equipment 6
702.55 Other equipment 6
702.55.101 Electric equipment for swimming pools 6
702.55.102 Underwater lighting for swimming pools 7
702.55.103 Electrical equipment for fountains 7
702.55.104 Special requirements for installation of low-voltage electrical equipment in Zone 1 of swimming pools 7
702.55.105 Heating systems in the ground and ceiling 7
Appendix A (informative) Regional example Figure 8
Reference 10
Figure A.702.1 Area of the swimming pool and paddling pool (side view) 8
Figure A.702.2 Area of the swimming pool and paddling pool on the ground (side view) 8
Figure A.702.3 Example of an area range with a fixed baffle of at least 2.5 m (top view) 9
Figure A.702.4 Example of determining the fountain area (side view) 9
Table 702.1 Minimum degree of protection (IP) for each zone 5
Foreword
GB/T 16895 "Low-voltage electrical installation" is divided into five parts, each part is divided into several sub-sections.
--- Part 1. Basic principles, assessment and definition of general characteristics;
--- Part 4. Security protection;
--- Part 5. Selection and installation of electrical equipment;
--- Part 6. Inspection;
--- Part 7. Requirements for special installations or locations.
This part is part 7-702 of the requirements of Part 7 of the special device or place of GB/T 16895.
This part is drafted in accordance with the rules given in GB/T 1.1-2009.
This part replaces GB/T 16895.19-2002 "Electrical installations of buildings - Part 7. Requirements for special installations or locations - Part 702
Festival. Swimming Pool and Other Pools. Compared with GB/T 16895.19-2002, the main technical changes in this section are as follows.
--- Improve the scope of application, including natural fountains, waterfalls and other places where people swim and play in water;
---Improve the division of the area and its description;
--- Added 702.55.1101.3 to set the technical safety requirements of the water supply pump;
---Update all drawings.
This section uses the translation method equivalent to IEC 60364-7-702.2010 (3rd edition) "Low-voltage electrical installations Part 7-702. Special
Facilities or places require swimming pools and fountains.
The documents of our country that have a consistent correspondence with the international documents referenced in this part are as follows.
---GB/T 5013-2008 (all parts) Rubber insulated cables with rated voltages of 450/750V and below [IEC 60245 (all)
Part), IDT];
--- GB 4706.66-2008 Particular requirements for safety pumps for household and similar electrical appliances (IEC 60335-2-41.2004,
IDT);
--- GB 7000.218-2008 Part 2-18.Special requirements for swimming pools and similar lighting (IEC 60598-
2-18.1993, IDT);
--- GB/T 20041.1-2005 conduit systems for electrical installation - Part 1. General requirements (IEC 61386-1.1996,
IDT).
Compared with IEC 60364-7-702.2010, this section has the same chapter number, the technical content is exactly the same, but the following editorial
modify.
---702.410.3.101.2 "0 and 1 area of the fountain" was changed to "0 area and 1 area of the fountain (the fountain that does not allow people to enter)";
---702.2 IEC 60529.1989 in the English version of the Normative Reference Document should be changed to IEC 60529.2001.
This part is proposed and managed by the National Building Electrical Equipment Standardization Technical Committee (SAC/TC205).
This section is responsible for drafting unit. Zhongji Zhongdian Design and Research Institute Co., Ltd.
Participated in the drafting of this section. China Power Engineering Co., Ltd., China International Engineering Design and Research Institute Co., Ltd., Siemens (中
Country) Limited.
The main drafters of this section. Huang Miaoqing, Wang Houyu, Wang Jianjun, He Youlin.
This part replaces GB/T 16895.19-2002.
introduction
This part of GB/T 16895 is required to supplement, modify or replace some of the provisions of Parts 1 through 6 of GB/T 16895.
The numbers after the 702 in this section are corresponding to the corresponding sections and sections in Parts 1 to 6 of the GB/T 16895 standard.
Number 1); therefore, the number of sections and bars does not need to be in order. The number of the added clause is indicated by the form ".101, etc.". this
The drawings of the parts and the numbers of the attached tables are arranged in the order of this part. The figures and tables of the appendix are numbered according to the letters, part numbers and sequence numbers of the appendix.
Said.
The parts, sections and strips that do not appear in the standard are described in the general requirements of Part 1 to Part 6 of GB/T 16895.
This section.
1) According to the previous statement, the numbers of GB/T 16895.1-2008 are as follows. 11 Scope of application, 12 normative references, 20 terms and definitions, etc.
Low voltage electrical installation
Section 7-702. Requirements for special installations or locations
Swimming pool and fountain
702 swimming pool and fountain
702.1 Scope
The specific requirements of this part of GB/T 16895 apply to electrical installations in the following locations.
--- swimming pool, paddling pool and its surrounding area;
--- Natural water areas for people to swim, play in water or other similar activities, gravel pit lakes and the sea and other similar areas and their surrounding areas.
These areas are also considered by swimming pool;
--- Fountain and its surrounding area.
Note. These areas increase the risk of electric shock during normal use due to reduced body resistance and contact between the human body and ground potential.
Medical swimming pools require special requirements.
This section does not cover the use of mobile devices such as pool cleaning equipment.
702.2 Normative references
The following documents are indispensable for the application of this document. For dated references, only dated versions apply to this article.
Pieces. For undated references, the latest edition (including all amendments) applies to this document.
GB/T 4208-2008 Shell protection class (IP code) (IEC 60529.2001, IDT)
GB/T 16895.21-2011 Low-voltage electrical installations - Part 4-41. Protection against electric shock (IEC 60364-4-41.
2005, IDT)
IEC 60245 (all parts) Rubber insulated cables with rated voltages of 450/750V and below (Rubberinsulatedcables-
Ratedvoltagesuptoandincluding450/750V)
Safety of household and similar electrical appliances - Part 2-41. Particular requirements for pumps (Household
similarelectricalappliances-Safety-Part 2-41.Particularrequirementsforpumps)
IEC 60598-2-18 luminaires - Part 2-18. Particular requirements for swimming pools and similar lamps (Luminaires-
Part 2-18. Particularrequirements-Luminariesforswimmingpoolsandsimilarapplication)
IEC 61386-1 - Conduit systems for electrical installation - Part 1. General requirements (Conduitsystemsforcablemanage-
ment-Part 1.Generalrequirement)
702.3 Terms and definitions
The following terms and definitions apply to this document.
702.3.1
Fountain fountain
Injecting water from a source of water into a certain type of pool (or a lower level of water) is a typical configuration of a landscape-decorated fountain.
702.3.2
Fountain pool (or water) basinoffountain
It is used for the water that flows out of the fountain.
Note. See also 702.30.101.
702.3.3
Swimming pool swimmingpool
The purpose of the setting is for people to swim, diving and other sports, not for the pool for people to clean.
702.3.4
Paddling pool paddlingpool
Used in low water pools such as playful or wading.
702.30 Assessment of general characteristics
702.30.101 General
The requirements listed in this section are based on Zone 0, Zone 1 and Zone 2 as described in 702.30.022~702.30.104 (see Figure A.702.1~).
Figure A.702.4) The size range of the three zones is specified.
Electrical equipment installed on the wall, floor or ceiling surface of the area divided by 702.30.102~702.30.104 shall also be satisfied.
Except for special requirements for the wall, floor or ceiling area (see 702.55).
A fixed partition with a minimum height of 2.5 m can be used to reduce the width of Zone 1 or Zone 2.
The requirements for the swimming pool also apply to the paddling pool.
Pools and stagnant waters that are expected to enter the fountain are subject to the regulations and requirements of Zone 0 and Zone 1 of the pool.
Note 1. The fixed partition is a fixed partition wall, including windows and doors. The area divided by it is defined by the slope of the ceiling, ceiling and floor. Below
The 2.5m fixed baffle is limited to the slope when it terminates to the ceiling or ceiling.
Note 2. The function of the fixed partition installed in a certain area is shown in Figure A.702.3.
Note 3. The requirements in this section also apply to factory prefabricated swimming pools.
Note 4. Appendix A provides examples of some regional divisions.
702.30.102 Description of Zone 0
Zone 0 includes.
---Pool, including any water on the wall of the pool or on the ground (see Figure A.702.1); and
---The inside of the foot bath; and
--- The space inside the spray column or artificial waterfall and underneath it (see Figure A.702.4).
Note. If the area of the spray column or waterfall cannot be accurately determined, it is recommended to use the vertical plane of the edge of the pool (or water) as the horizontal boundary of the area.
Limit, and the highest height of the water jet or waterfall as its height limit.
702.30.103 Description of Zone 1
---0 zone boundary line;
--- 2m from the edge of the pool (or water);
---The ground or surface that is expected to be occupied by someone;
--- Higher than expected on the ground or surface of the surface 2.5m.
Note. Equipment installed in the outer guard (housing) that cannot be accessed under the ground, on the wall or under the ceiling, is not considered for equipment within Zone 1 (see 702.55.131.3).
When the swimming pool has a platform, springboard, slide or other area that is expected to be accessible, the area bounded by Zone 1 is.
--- 1.5m around the platform, springboard, slides or other parts (such as sculpture and decorative pools that may be touched. see Figure A.702.1)
Vertical surface
--- Higher than expected to occupy the floor or other horizontal surface of the highest level of 2.5m.
702.30.104 Description of Zone 2
The boundaries of Zone 2.
- the vertical surface of the outer edge of the -1 zone and the parallel plane of 1.5 m from the vertical plane;
---The ground or surface that is expected to be occupied by someone; and
--- Higher than expected to occupy the ground or surface level of 2.5m.
The fountain has no 2 zones.
Note. Equipment installed in the enclosure that is not accessible under the ground, on the wall or on the ceiling is not considered for equipment in Zone 2 (see 702.55.131.3).
702.4 Security protection
702.41 Protection against electric shock
Add the following.
Note 1. See 702.53 for the selection and installation of power sockets.
Note 2. See 702.55 for the selection and installation of other equipment.
702.410.3 General requirements
702.410.3.5 Barriers and protection placed outside the reach of the arm shall not be used in accordance with Annex B of GB/T 16895.21-2011
the way.
702.410.3.6 Non-conducting places and ungrounded local equipotential bonding in accordance with Annex C of GB/T 16895.21-2011 shall not be used.
Junction and protection of electrical separation from one or more electrical equipment.
702.410.3.101 Special requirements for each zone
702.410.3.101.1 Zone 0 and Zone 1 of the swimming pool as well as natural water zones, gravel pit lakes, seaside and similar areas
Except as described in 702.55.14, Zone 0 and Zone 1 are only allowed to use a nominal voltage not greater than AC 12V or DC 30V.
SELV protection method. Its power supply should be installed outside Zone 0 and Zone 1. When the power supply is installed in Zone 2, the provisions of 702.53 are implemented.
702.410.3.101.2 Zone 0 and Zone 1 of the fountain (the fountain that does not allow people to enter)
Only the following protective measures can be used in Zone 0 and Zone 1.
---SELV (see 414 of GB/T 16895.21-2011), its power supply is installed outside Zone 0 and Zone 1; or
--- Use the residual current protector with rated residual operating current not more than 30mA to automatically cut off the power supply (see GB/T 16895.21-
Section 411 of.2011); or
---Electrical separation (see section 413 of GB/T 16895.21-2011), separate power supply to only one device, its power supply
Installed outside Zone 0 and Zone 1.
702.410.3.101.3 Zone 2 of the swimming pool and natural water area, gravel pit lake, seaside and similar areas
Note. The fountain does not have 2 zones.
Only one or more of the following protection methods should be used.
---SELV (see section 414 of GB/T 16895.21-2011), its power supply should be installed outside Zone 0 and Zone 1. When it is available
When the electric power supply is installed in Zone 2, the provisions of 702.53 are implemented; or
--- Use the residual current protector with rated residual operating current not more than 30mA to automatically cut off the power supply (see GB/T 16895.21-
Section 411 of.2011); or
---Electrical separation (see section 413 of GB/T 16895.21-2011), separate power supply to only one device, its power supply
It should be installed outside Zone 0 and Zone 1. When the power supply is installed in Zone 2, the provisions of 702.53 are implemented.
702.414 Protection mode. Safety Extra Low Voltage (SELV) and Protection Extra Low Voltage (PELV)
702.414.4 Requirements for SELV and PELV circuits
Add the following
PELV is not allowed.
702.414.4.5
Add the following
When using SELV, the following basic protection (direct contact protection) measures should be taken regardless of the nominal voltage.
--- The degree of protection is at least the obstruction or casing of IP2X or IPXXB specified in GB/T 4208-2008;
---Insulation can withstand a test voltage of 500V for 1min AC.
702.415 Additional protection
702.415.2 Additional protection. auxiliary protection equipotential bonding
Conductive parts outside all devices in Zone 0, Zone 1 and Zone 2, shall be connected with protective equipotential bonding conductors and equipment outside these zones
The protective conductors of the conductive portion are connected.
Note 1. It can be connected to the protective conductor in close proximity to electrical accessories, switchboards or other equipment.
Note 2. See also 702.522.8 and 702.55.11.
The conductive part outside the device is not part of the electrical device, it is possible to introduce a potential including the local ground potential - for the standard
For the purposes of this section, it is meant that the potential is introduced into these regions from outside the 0, 1, and 2 regions.
Note 3. Examples of these parts are as follows.
---Metal pipe for fresh water, wastewater, gas, heating and temperature control;
---Metal components of the building structure;
---Metal components of the pool structure;
--- Rebar in non-insulated ground;
--- Rebar for concrete pools.
For concrete floor tiles with steel bars, the steel bars are sealed in the concrete floor tiles, and the human body is not damaged by the concrete floor tiles.
It does not touch the steel bar, it does not consider the conductive part outside the device, so it is not necessary to incorporate the additional protection equipotential bonding.
Reinforced concrete floor tiles and their outer sheaths and topsoil (such as grass) are not considered for the conductive parts outside the device, and do not need to be included
Protect the equipotential bonding.
Note 4. The following conductive parts are usually not required to be included in the additional protection equipotential bonding.
---The ladder and shelter of the pool;
---The ladder of the springboard;
---Handles and handrails on the edge of the pool;
--- Grid cover including overflow hose brackets;
---window frame;
---door frame;
---Starting the platform.
702.5 Selection and installation of electrical equipment
702.51 General rules
702.512 Conditions of use and external influences
702.512.2 External influence
Electrical equipment shall have at least the degree of protection specified in Table 702.1 (see GB/T 4208-2008).
Table 702.1 Minimum degree of protection (IP) for each zone
The area is sprayed with water for cleaning. The outdoor is not sprayed with water. The indoors are sprayed with water to clean the house without spraying water.
0 IPX5/IPX8 IPX8 IPX5/IPX8 IPX8
1 IPX5 IPX4 IPX5 IPX4
2 IPX5 IPX4 IPX5 IPX2
Note 1. GB/T 4208-2008 indicates that there should be agreement between the user and the manufacturer regarding the test conditions of IPX8 unless there is a relevant product standard.
Note 2. When it is expected to use water spray for cleaning, use IPX5 for Zone 0 (to ensure waterproof performance in water spray cleaning) and IPX8 (to ensure water immersion)
Water resistance) is required (see. 4.3 in GB/T 4208-2008). Both IPX5 and IPX8 are required because IPX8 does not have
Water spray prevention.
702.52 wiring system
702.522 Selection and installation principles related to external influences
702.522.8 Other mechanical stress
702.522.8.101 Installation method determined by region category
Wiring systems in Zone 0, Zone 1 and Zone 2 should not have accessible metal covers. Metal cover that cannot be touched should be supplemented
Help the equipotential bonding to connect.
Note. The cable should be laid in the conduit to change the line.
702.522.8.102 Restrictions on cabling systems by region category
Cabling systems in Zone 0 and Zone 1 should be limited to circuits that only supply power to equipment located in the zone.
Circuits installed in Zone 2 or in walls, ceilings or floors defining Zone 0, 1 or 2 and supplying power to equipment outside these zones shall be
One of the following requirements.
--- The buried depth is at least 5cm;
---Residual current protector with rated residual operating current not more than 30mA;
---Powered by SELV;
--- Use electrical separation protection.
702.522.8.103 Additional requirements for fountain wiring
Only type 66 cables complying with the IEC 60245 series or cables with at least equivalent performance should be used.
Note. The manufacturer shall indicate that the cable is suitable for long-term contact with water, in addition to the requirements of IEC 60245-1 and IEC 60245-4.
Only those catheters that comply with the IEC 61386-1 anti-collision performance and the ×5×× coding category should be used.
For fountains that are not accessible, the following additional requirements should be met.
a) Cables or insulated conductors of electrical equipment in Zone 0 that are laid on non-metallic conduits should be as far as possible from the outer edge of the pool, in the pool
The line should be connected to the device with the shortest possible path. These cables should be laid in the conduit to change the line;
b) Cables or insulated conductors laid in non-metallic conduits in zone 0 and zone 1 shall have suitable mechanical protection.
702.522.8.104 junction box
A junction box should not be installed in Zone 0.
Only the junction box for the SELV circuit is allowed in Zone 1 (see 702.410.3.101).
702.53 Switchgear and control equipment
Switching or control equipment and power outlets should not be installed in Zone 0.
Only switchgear or control equipment and power outlets for the SELV circuit are allowed in Zone 1, and the power supply is installed in Zone 0 and
Outside the 1st district. When installing the SELV power supply in Zone 2, the power supply circuit in front of the power supply equipment shall adopt the rated residual operating current not exceeding
30mA residual current protector.
Switching devices, control equipment and power outlets are not permitted in Zone 2 unless one of the following protective measures is used.
a) SELV (see 414.3 of GB/T 16895.21-2011), whose power supply is installed outside Zone 0 and Zone 1. When SELV is powered
When the source is installed in Zone 2, the power supply circuit in front of the power supply equipment shall use the residual current with a rated residual operating current of not more than 30 mA.
protector;
b) Residual current protector with rated residual operating current not more than 30mA as additional protection for automatic power cut protection
(See 415.1 of GB/T 16895.21-2011);
c) Electrical separation (see section 413 of GB/T 16895.21-2011), separated by a separate power supply installed in Zone 0 and Zone 1
Electricity. When the electrically separated power supply is installed in Zone 2, the power supply circuit in front of the power supply equipment shall adopt the rated residual operating current is not large.
Residual current protector at 30mA.
702.55 Other equipment
702.55.101 Power equipment for swimming pools
702.55.101.1 Only fixed-type electrical equipment for swimming pools can be installed in Zone 0 and Zone 1, but 702.55.12 and
702.55.104 requirements.
702.55.101.2 Swimming pool cleaning equipment for fixed connection in Zone 0 and Zone 1 shall be used not exceeding 12V AC or straight
It is powered by a 30V SELV, and its power supply is installed outside Zone 0 and Zone 1. When the power supply is installed in Zone 2, it shall comply with the provisions of 702.53 (see
702.410.3.101.1).
702.55.101.3 The water supply pump or other special electrical equipment for the swimming pool is installed in the room or place (compartment) near the swimming pool.
Access to these electrical equipment is required by access to manholes or doors on the ground, and these electrical equipment should employ one of the following protective measures.
a) SELV not larger than AC 12V or DC 30V, its power supply is installed outside Zone 0 and Zone 1. When the SELV power supply
When installed in Zone 2, it shall be implemented in accordance with 702.53 (see 702.410.3.101.1).
b) meet the requirements for electrical separation in Section 413, while satisfying the following conditions.
--- Pumps or other equipment should be connected to the swimming pool by connecting pipes of non-conductive materials;
--- Only use the key or tool to open the manhole cover or door;
--- All equipment installed in the room or space (compartment) should have at least IPX5 protection or use the casing to reach
Protection requirements to this degree of protection.
c) Adopt automatic power cut-off power supply measures, and simultaneously meet the following conditions.
---When pumps or other equipment are connected to the swimming pool, water pipes made of electrically insulating materials or metal water pipes should be included
Pool equipotential bonding system;
--- Only use the key or tool to open the above manhole cover or door;
--- All electrical equipment installed in the above rooms or premises should have at least IPX5 protection level or use the outer casing to achieve
Protection requirements for this degree of protection;
--- The setting of the additional equipotential bonding shall comply with the provisions of 702.415.2;
--- Electrical equipment should be equipped with a residual current protector with a rated residual operating current of not more than 30 mA.
Note. The room (compartment) in which the above equipment is located is considered outside the Zone 1 and Zone 2.
702.55.102 Underwater lighting of swimming pool
Luminaires used for underwater or in contact with water shall comply with IEC 60598-2-18.
Any underwater vehicle that is installed behind a viewing window that meets watertight requirements and that faces the pool from the ground shall be any
There is no intentional or unintentional conductive communication between the exposed conductive portion and any electrically conductive portion of the viewing window.
702.55.103 Electrical equipment for fountains
Electrical equipment in Zone 0 and Zone 1 shall be unreachable, such as wire glass or grid that can only be removed with tools.
Separated.
Electric pumps shall comply with the requirements of IEC 60335-2-41.
702.55.104 Special requirements for installation of low-voltage electrical equipment in Zone 1 of swimming pools
702.55.104.1 Stationary equipment (such as filtration equipment, jet pumps) dedicated to the swimming pool with low voltage supply is allowed to be installed in Zone 1.
However, all of the following requirements should be met.
a) that the equipment shall be located in an enclosure having an equivalent insulation that is resistant to mechanical shocks of the AG2 class;
b) meet the requirements of 702.55.1101.3;
c) When opening the manhole cover as described in 702.55.1101.3, all live conductors of the equipment contained in the enclosure shall be cut off at the same time. powered by
The setting of the cable and the main power-off electrical equipment shall be insulated or insulated according to the requirements of Class II equipment against electric shock.
702.55.104.2 For swimming pools without Zone 2, the lighting equipment installed on the wall or ceiling of Zone 1 may be large when the following requirements are met.
Powered by a SELV circuit with AC 12V or DC 30V (see 702.410.3.101.1).
---The circuit should adopt automatic power cut-off protection measures, and install the residual current with rated residual operating current not more than 30mA.
Protector as an additional protection; and
--- The height of the bottom of the luminaire is at least 2m higher than the relatively high level in Zone 1.
702.55.105 Heating systems in the ground and ceiling
Note. See also IEC 60364-7-753.
Installation of an electric heating unit buried under the ground and mounted on the ceiling may be protected by one of the following conditions.
---SELV (see section 414 of GB/T 16895.21-2011), its power supply is installed outside Zone 0 and Zone 1. When the power
When installed in Zone 2, the provisions of 702.53 are implemented;
---Automatically cut off the power supply, the heating unit is covered with a metal mesh or metal sheath buried in the ground, and according to 702.415.2
It is specified to be connected to the auxiliary equipotential bonding system. The power supply circuit should adopt a rated residual operating current of not more than 30mA.
The residual current protector acts as an additional protection.
Appendix A
(informative appendix)
Area example map
Note. The final determined area size depends on the location of the wall and partition concerned.
Figure A.702.1 Area of the swimming pool and paddling pool (side view)
Note. The final determined area size depends on the location of the wall and partition concerned.
Figure A......
 
Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.