ISO/DIS 20288:2026(en)

ISO/TC 83

Secretariat: DIN

Date: 2025-12-11

Public Swimming Pools — Systems recognizing involuntarily submersion of humans in managed aquatic facilities

© ISO 2026

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Contents

Foreword v

Introduction vi

1 Scope 1

2 Normative references 1

3 Terms and definitions 1

4 General 2

5 Pre-drowning behaviours 2

5.1 General 2

5.2 Submersion with struggle 3

5.3 Submersion without struggle 3

5.4 Inactive person at the water surface 3

6 System requirements 3

6.1 Technical Study 3

6.1.1 General 3

6.1.2 Design information 3

6.1.3 Operational information 4

6.1.4 Technical information 4

6.1.5 Performance information 4

6.2 System performance 4

6.3 Minimising the number of false notifications 5

7 Testing 5

7.1 General 5

7.2 Test subject 5

7.2.1 Test with a human 5

7.2.2 Test with a mannequin 5

7.3 Coverage areas 6

7.4 Test procedures 7

7.4.1 Submersion with struggle 7

7.4.2 Submersion without struggle 7

7.4.3 Inactive person at the water surface 8

7.4.4 Test result 8

8 Test report 8

9 Training 8

10 Maintenance 9

Annex A (informative) Test report 10

Annex B (informative) Additional variations of submersion with struggle 12

B.1 Instinctive drowning response 12

B.2 Backward water milling 12

B.3 Climbing the ladder movement 12

B.4 Moving while jumping up and down 12

Annex C (informative) Mannequin test procedures 13

C.1 General requirements 13

C.2 requirements for the submersion with struggle 13

C.3 Submersion without struggle 13

C.4 Inactive person at the water surface 13

Bibliography 15

Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

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This document was prepared by Technical Committee ISO/TC 83, Sports and other recreational facilities and equipment.

Any feedback or questions on this document should be directed to the user’s national standards body. A complete listing of these bodies can be found at www.iso.org/members.html.

Introduction

Lifeguards can supervise swimming pools, identify hazards and educate swimmers to help ensure their safety, and in the event of an emergency intervene early to prevent an accident from occurring or perform a rescue.

The use of technology systems to help lifeguards detect incidents in swimming pools has grown in recent years.

For several reasons (physiological, cognitive, architectural, organisational, etc.), lifeguards can sometimes find it difficult to identify hazards and foresee incidents. Technology can assist lifeguards in identifying hazards.

ISO 20288 is a standard that defines the requirements and test methods for recognising involuntary submersion at the beginning and throughout the incident trajectory, before the victim is stationary on the bottom.

The goal of the ISO 20380, Public swimming pools - Computer vision systems for the detection of drowning accidents in swimming pools - Safety requirements and test methods is to trigger an alarm at the end of the incident trajectory after detection of a stationary solid mass at the bottom of the pool.

These standards can be used separately or parallel. Technology cannot guarantee 100 % effectiveness and reliability. Systems recognizing involuntary submersion of humans are foreseen to support the competent person. These systems do not save people, as saving a victim of involuntary submersion necessarily requires human intervention.

Within this document, certain techniques are mentioned such as video and artificial intelligence (AI) as they are currently common solutions. However, any other techniques that can fulfil the requirements are valid.

Public Swimming Pools — Systems recognizing involuntarily submersion of humans in managed aquatic facilities

This document specifies minimum requirements and test methods for systems recognising involuntarily submersion of humans in managed public aquatic facilities.

It specifies the function, operation and performance of systems recognising involuntarily submersion of humans in managed public aquatic facilities.

It is applicable to managed aquatic facilities such as indoor pool, outdoor pools and natural pools.

There are no normative references in this document.

For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminology databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https://www.iso.org/obp

— IEC Electropedia: available at https://www.electropedia.org/

3.1

aquatic facilities

indoor pool, outdoor pool, natural water pool or beach

3.2

pool/ swimming pool

facility, with one or more water areas, intended for swimming, leisure or other water based physical activities

[SOURCE: EN 15288-1:2018+A1:2024, 3.1]

3.3

indoor swimming pool

one or more constructed water areas for bathing enclosed in a building, covered by a roof (fixed or moveable)

[SOURCE: EN 15288-1:2018+A1:2024, 3.2]

3.4

outdoor swimming pool

one or more constructed open-air water areas for bathing

[SOURCE: EN 15288 -1:2018+A1:2024, 3.3]

3.5

natural pool

natural water body (e.g. lakes, rivers, splash pool) having a defined area for swimming as distinct from other recreational water activities (e. g. boating, canoeing, fishing)

3.6

drowning

process of experiencing respiratory impairment from submersion/immersion in liquid the consequence of which is classified as death, morbidity and no morbidity

3.7

competent person

designated individual who has acquired through training, qualifications or experience, or a combination of these, the knowledge and skills enabling that person to perform a specified task

[SOURCE: ISO 20380:2017, 3.6]

3.8

pre-drowning behaviour

human behaviours occurring before final submersion which could lead to a drowning accident

3.9

involuntary submersion

unintentional submersion which could lead to drowning

3.10

notification

a method to alert a system user to the occurrence of a pre-drowning behaviour.

3.11

true notification

a notification corresponding to the recognition of an instance of pre-drowning behaviour according to the conditions and definitions described in this standard

3.12

false notification

any notification that is not a true notification

3.13

representative pool

pool for a laboratory test with following sizes: length 25 m and at minimum 1,8 m depth

This document defines minimal performance requirements. Knowing that all systems have limits, these limits shall be identified and described by the producer.

Installation and use of systems recognizing involuntary submersion of humans cannot serve as a reason to reduce human monitoring of swimming pools, unless a robust risk assessment does indicate this is possible without compromising safety, with reference to applicable national regulations, if any.

The recognition of pre-drowning behaviours by a technical system requires identifying important criteria that can identify situations that could lead to a drowning. A system has first to recognise and identify which behaviours that are a precursor to a drowning situation. People at risk of a drowning can exhibit distinct ways that are not unique to other persons in the same vicinity. It is important to define as many reasonably foreseeable behaviours that could lead to a potential drowning.

A great variety of possible pre-drowning behaviours exist. Not all can be considered when defining the tests in this document.

The different variants of pre-drowning behaviours that will be tested according to this document are described in 5.2, 5.3 and 5.4.

Submersion with struggle is demonstrated by a person in the pool basin, with a horizontal displacement smaller than 2 m, moving up and down, having head submerged at least 3 times with at least 20 s of cumulated time underwater over the course of 45 s.

Additional variation of submersion with struggle, see Annex B, can be observed.

Submersion without struggle is demonstrated by a person submerging in the pool basin and remaining submerged for 30 s, with a horizontal displacement smaller than 4 m.

An inactive person is demonstrated by their torso mainly at the water surface, face down in the water, without apparent movement and with a horizontal displacement smaller than 2 m over the course of 45 s.

Prior to any installation of a technical system recognising involuntary submersion, a technical study shall be carried out by the supplier in consultation with or based on information provided by the facility owner/operator.

Depending on the technical system proposed, the technical study is used to quantify and to position the equipment making up the system, such as sensor devices, computing hardware, notification tools and related equipment, in a document. The technical study shall be provided to the responsible parties (e.g. facility owner/operator) by the manufacturer.

The design of a swimming pool has a great influence on the operation of the pool.

Supervision of a pool depends on design factors such as the ability to see above and below the water surface, the layout of the pool or equipment that could restrict the view of the supervision staff.

The following information shall be provided by the owner/operator of the pool:

— indoor or outdoor pool;

— specific equipment: moveable floor, moveable bulkhead, wave machine and all equipment able to generate water movement;

— texture and colour of the pool basin lining, e.g. tiling, stainless steel, PVC, resin;

— layout of the swimming pool, especially regarding the positions of pool basins;

— position, size and layout of windows;

— position, size and layout of underwater observation features;

— obstructions in the view of the technical detection system;

— depths of the pool basin;

— pool attractions e.g. waterslide;

— existence of water features such as jets, fountains, streams, waterfalls, etc. that can introduce turbidity, bubbles or movement of the water.

The deployment of a system to recognize involuntarily submersion also depends on the operational conditions in a swimming pool.

The following information shall be provided by the operator prior to the installation of the system:

— pool occupancy;

— type of use e.g. diving pool, swimmer- or non-swimmer-pool;

— number and location of lifeguards;

— training of staff regarding pool supervision and the system to recognize involuntarily submersion.

The following technical information shall be provided by the owner/operator:

— water turbidity;

— glare on the water surface;

— reflection on the water surface;

— turbulences in the water and at the water surface;

— lighting conditions (daylight, artificial light);

— type and position of installed lighting components.

The following information shall be provided by the manufacturer:

— recognition capacity of the system based on design/operational/technical criteria;

— clear roadmap regarding the number of notifications and recognition capacity forecasted for the system over time. After the commissioning phase the number of false notifications shall not exceed 15 per day and per pool basin;

— notification reception coverage area of mobile devices;

— notification set off time in seconds;

— areas of the pool basin where the system is functional;

— the minimum level of artificial lighting required above and below the water surface (illuminance in lux) to enable recognition by the system in accordance with the performance requirements.

As long as the conditions laid out in the technical study are met, the system shall at minimum fulfil the following requirements:

— recognise all three types of involuntary submersion behaviour;

— ensure trained staff is notified, to take action in time to save life;

— keep the number of false notifications leading to an unnecessary emergency response by staff under the allowed limit of 15 per day and per pool basin;

— notify the users when the system is non-functional (fail to safety).

Ensure that the coverage specified in the technical study is indeed covered.

When installed, a system will complete a commissioning phase. For the system to be compliant with this document following the commissioning phase, the average number of false notifications per day over a monthly period shall not exceed 15 per day and per pool basin.

The recognition of pre-drowning behaviours and alerting of staff by the system shall be demonstrated by the test procedure described below. Technical systems cannot go into operation unless it complies with the test requirements of this document.

ISO requirements define that test methods shall be repeatable and reproducible. This shall be considered when the test is carried out with human test persons, to the extent that is possible.

The testing procedure shall be conducted to verify that the system recognizes involuntary submersion in multiple areas of the pool.

The tests shall be carried out in a representative pool as well as in the built-in situation.

If the test is carried out in a representative pool, the system shall be installed in this pool according to the manufacturer’s instructions. The notification shall be received on all connected receivers. Passing the test in this representative pool will demonstrate compliance of the system to the standard.

If the test procedure takes place in the built-in situation, the system shall be tested after installation according to the manufacturer’s instructions under conditions that correspond to the reasonably foreseeable use. The entire system shall be tested under various conditions with all sensor devices. The notification shall be received on all connected receivers. The test in a representative pool shall be passed for the commissioning of the system.

If the test in the representative pool has been passed, the test in the built-in situation can be carried out as a sample test.

NOTE Operator should consider intermediate regular tests, e. g. every 6 months, carried out accordingly.

The tests shall be carried out by competent persons.

The test subject can be a human or a mannequin, where it is not possible to use a human.

In case of a human the following requirements shall be met:

— the human is educated as a rescue diver, lifeguard etc., is able to simulate a casualty situation;

— the human is able to understand and follow the test instructions;

— the human shall be able to exhibit the behaviours to be tested in a correct, uniform and repeatable manner;

— different humans should be available to perform the testing. Gender, age and ethnicity should be taken into account.

If a mannequin is used the following requirements shall be met:

— the mannequin shall be similar to a human being (e.g. rescue puppet);

— a rope shall be provided long enough to move the mannequin in the middle of the pool;

— a means shall be provided to guide the rope on the pool bottom, e.g. suction handle or kettlebell (minimum 24 kg);

— the buoyancy of the mannequin shall be adjusted according to the test procedure in 7.4;

— the move of the mannequin shall be carried out by technical means in a way most similar to the natural movement.

The pool shall be divided in test areas of 4 m by 4 m as shown in Figure 1 as an example. This should be adapted to the size and form of all pools used for the test and documented before the test.

The test shall be carried out in every test area.

Dimensions in metres

Figure 1 — Example of coverage areas

The producer shall clearly define in the technical study the area that is covered by the system. Uncovered areas can be accepted but the user should have clear understanding of them.

A test shall be done for all the positions in the defined/chosen grid according to Figure 2, however only one behavior type needs to be tested per position. At minimum every behaviour shall be tested once.

NOTE Recommended is 1/3 of the total number of tests per behaviour.

Key

A submersion with struggle

B submersion without struggle

C inactive person at the water surface

Figure 2 — Distribution of test in a 25 m pool with at least 1,5 m water depth

The behaviours with struggle shall be tested only if the test person cannot have the head above the surface while touching pool bottom with the feet.

The test areas shall be defined regarding the pool tanks characteristics. For example, see Figure 3, when a defined section of one pool tank is shallow water, submersion with struggle cannot be performed. In this case only the submersion without struggle and inactive person at the water surface can be tested.

Key

<graphic></graphic> deep shallow

A submersion with struggle

B submersion without struggle

C inactive person at the water surface

Figure 3 — Example for a 25 m pool where water depths do not allow the testing of Submersion with struggle

For all systems which continuously identify people entering the water the test begins with the entry into the water, excluding those people who enter the water falling into the water.

The test procedures in this document are defined on the basis of the related behaviours in 5.2, 5.3, 5.4. Each of the tests shall be carried out with 1 test in each test area.

Any system to prevent involuntary submersion shall only be put into operation after having passed the test procedures defined in this document.

The test subject (TBD) shall be in the basin, move to the test location, and then while limiting its horizontal displacement to a maximum of 2 m, should submerge at least 3 times over the course of 45 seconds with a total of 20 s of cumulative time underwater.

The test shall be considered successful if the system notifies the user of a suspicious behaviour within 45 s (+/-5 s) since the beginning of the first submersion.

The mannequin shall be placed to the grid location at the surface in the basin in a horizontal position and be allowed to sink while ensuring that its horizontal displacement is kept within 4 m.

The test shall be considered successful if the system notifies the user of a suspicious behaviour after the mannequin has been submerged for 30 s (+/-5 s).

The test subject (TBD) shall be in the basin, move to the test location, then position itself with the torso substantially at the water surface, being partially submerged, face down in the water, without apparent activity and with a horizontal displacement smaller than 2 m over the course of 30/45 s.

The test shall be considered successful if the system notifies the user of a suspicious behaviour within 30/45 s (+/-5 s) since assuming the test conditions.

The total test result over all tests shall be ≥ 80 %.

For each single behaviour the total test result shall be ≥ 60 %.

The test report shall include at least the following information:

— name and address of testing body and location where the test was carried out when different from the address of the test body;

— unique identification of report (such as serial number) and of each page, and total number of pages of the report;

— reference to this document;

— name and address of client;

— description and identification of the test item;

— identification of the test specification or description of the method or procedure;

— description of sampling procedure, where relevant;

— any deviations, additions or exclusions from the test specification, and any other information relevant to a specific test;

— measurements, examinations and derived results, supported by tables, graphs, sketches and photographs/screenshots as appropriate, and any failures identified;

— a statement on measurement uncertainty (where relevant);

— signature and title or an equivalent marking of person(s) accepting technical responsibility for the test;

— report and date of issue;

— statement to the effect that the test results relate only to the items tested.

An example for a test report is given in Annex A.

Training the operation of a system for the recognition of involuntarily submersion sets the special requirements for any of such systems and for the staff of the pool. These are systems, which require a continuous interaction between humans and the machine.

Staff shall be competent in all aspects of the system. The supplier shall provide the initial training following the installation of the system and before it is used for the first time. The training shall include at least the understanding of the system’s functions, capabilities and limitations.

The supplier shall offer maintenance services for the upkeep of the system installed. The system shall be maintained regularly according to the manufacturer's guidelines.

Maintenance shall include as a minimum:

— maintenance of hardware, if any, (e.g. sensor (dirtiness, correct position), receivers (function test, battery test));

— maintenance of software, if any (monitoring, repairs, updates, upgrades).

1. 
   (informative)
   
   Test report

TEST REPORT ISO 20288

Facility Name: _________________________________

Facility Address: _________________________________

Report UID: : _________________________________

(UID: date as YYYYMMDD followed by Facility Name)

Procedure Carried out by: _________________________________

(Name of person(s) conducting the test, title/role and company(ies) the person(s) is(are) from)

Test method according to ISO 20288

Date of test: _________________________________

(date as YYYYMMDD)

Time it was conducted, between: ______________________and ____________________

Short description of how the test was performed:

(Using Mannequin, human. Any relevant other accessory used. Join a picture of each device)

Pool size: ________________________________

(A meters x B meters. Note if odd shape then uses the smallest rectangle dimensions in which the pool fits)

Pool depths, between: ______________________and ____________________

Number of cells: ________________________________

Cell layout:

(example 25 x 15 m pool)

Total test result >= 80 %: Yes / No

Each single behaviour test result >= 60 %: Yes / No

Test type: use the following acronyms.

Possibilities: M-SWS M-SWO M-IN H-SWS H-SWO H-IN

Comments: _________________________________

1. 
   (informative)
   
   Additional variations of submersion with struggle
   1. Instinctive drowning response

Additional criteria for the IDR could be

— head backwards;

— beating the water surface with hands and arms laterally.

• 1. Backward water milling

Additional criteria for the backward water milling could be

— a person moving arms in circles from front to back;

— head backwards.

• 1. Climbing the ladder movement

Additional criteria for the Climbing the ladder movement could be

— hands and legs moving up and down alternatively;

— arms and body mostly under water.

• 1. Moving while jumping up and down

Additional criteria for the jumping up and down could be

— having partly contact to the ground;

— jump movement from the ground;

— jumping in one place.

1. 
   (informative)
   
   Mannequin test procedures
   1. General requirements

The mannequin test for the different pre-drowning behaviours should be carried out moving the mannequin as similar to the human movements as possible.

• 1. requirements for the submersion with struggle

For carrying out the test for the submersion with struggle these additional requirements should be met:

— the suction handle or the kettlebell (minimum 24 kg) should be placed on the pool bottom (basin floor) in the set location;

— the mannequin should have a rope tied to the foot ankles;

— the rope should pass from the mannequin through the handle/kettlebell to the pool edge where a person will hold the rope;

— the mannequin should start floating at the surface;

— the rope should be pulled so that the mannequin submerges under the surface until the head is covered by water.

For the test following persons should be available:

— one person to fix and adjust the handgrip (diver);

— one person pulling the rope;

— one person to fulfil the test report.

• 1. Submersion without struggle

For the submersion without struggle these additional requirements should be met:

— the mannequin should have a rope tied to the body;

— the position of the rope and the buoyancy aid should be adjusted so that the mannequin lies horizontal at the water surface;

— the mannequin should start at the surface;

— the rope should be pulled so that the mannequin submerges under the water surface slowly towards the pool bottom but not reach it.

• 1. Inactive person at the water surface

For the inactive person at the water surface these additional requirements should be met:

— the mannequin should have a rope tied to the body;

— the mannequin wears or can lie on the buoyancy aid which will make the mannequin float at the surface;

— the position of the rope and the buoyancy aid should be adjusted so that the mannequin lies horizontal at the water surface;

— arms and legs of the mannequin should hang down under the water surface.

Bibliography

EN 15288, Swimming pools for public use - Part 1: Safety requirements for design

ISO 20380, Public swimming pools — Computer vision systems for the detection of drowning accidents in swimming pools — Safety requirements and test methods

Carballo-Fazanes, Aida; *, Bierens, Joost J.L.M.: The Visible Behaviour of Drowning Persons: A Pilot Observational Study Using Analytic Software and a Nominal Group Technique

Canadian Lifesaving Manual, Royal Life Saving Society Canada