BS EN 246:1992 download.Sanitary tapware General specifications for flow rate regulators.
1 Scope
BS EN 246 aims to establish:
— the dimensional, hydraulic and acoustic properties to which flow rate regulators intended to be mounted on sanitary tapware shall correspond:
— the test methods whereby these properties may be verified.
2 Field of application
BS EN 246 applies to flow rate regulators intended to be mounted on tapware fitted on sanitary appliances installed in toilets and washrooms and kitchens (single, mixer, thermostatic mixer taps….).
3 References
ISO 49:1983, Malleable cast iron fittings threaded to
ISO 7-1.
ISO 228-1:1982, Pipe threads where pressure-tight
joints are not made on the threads — Part 1: Designation, dimension.s and tolerances.
Iso 2768:1973, Permissible machinery variations in dimensions without tolerance indication.
ISO 3822-1:1983, Acoustics — Laboratory test noise ernissio from appliances and equipment used in water supply installations — Part 1: Method of measurement.
ISO 3822-4:1985. Acoustics — Laboratory tests on noise emission from appliances and equipment in water supply installations — Part 4: Mounting and operating conditions for special appliances.
EN 200:1989, Sanitary tapware— General technical specifications for single and mixer taps (designation ½).
EN 248:1989, Sanitary tapware — General specifications for Ni-Cr surface metal coatings.
4 Definitions or appliances
The flow rate regulators are devices which are fitted on the diverter head of a tap to enable its flow rate to he regulated.
They are called:
— interrupters — flow or low rate regulator without air intake, if operation is possible without aeration of the water;
— aerators or flow rate regulators with air intake, if aeration of the water is ensured:
— swivel flow rate regulator, if the aerator or interruptor has a swivel joint.
5 Designation
A flow rate regulator is designated by:
— its appellation:
— its dimension;
— its flow rate class;
— reference to this standard EN 246.
Example of designation
Flow interrupter (or flow rate regulator without air
intake) with internal thread
M22x 1—A—EN 246.
6 Materials
6.1 Chemical and hygienic behaviour
All the materials in contact with water intended for human consumption shall present no danger to health up to a temperature of 90 °C. They shall not bring any deterioration in the water intended for human consumption, either with regard to nutritional quality, appearance, smell or taste.
In normal conditions of use, the materials shall not be subject to any deterioration involving the operation of the regulator; materials which do not have adequate corrosion resistance shall be protected against corrosion.
6.2 Condition of visible surfaces
The visible surfaces shall comply with the requirements of EN 248.
6.3 Quality of the coating
The coating shall comply with the requirements of
EN 248.
7 Dimensional properties
NOTE For the values without. tolerances, the ISO 2768 tolerances are applicable.
7.1 Regulator connected with internal thread
Case 2: The swivel joint is independent of the flow rate regulator (Figure 4).
In this case:
a) The flow rate regulator dimensions for the connection with swivel joint shall meet the requirements of Table I (internal thread) or of Table 2 (external thread) for the connection with the diverter head.
b) The swivel joint dimensions for the connection with flow rate regulator shall meet the requirements of Table 10 (for flow rate regulators with internal thread M22 x 1) or Table 11 (for flow rate regulators with external thread M24 X 1 or M28 X 1) of the standard EN 200. (The Tables 10 and 11 of EN 200 are given in the Annex A.)
8 Hydraulic properties
8.1 Flow rate
8.1.1 Requirements
Flow rate regulators are classed according to their nominal flow rate at a dynamic pressure of 0,3 MPa (3 bar), with the following tolerances:
8.1.2.2 Test methods
Fit the flow rate regulator on the adaptor 4 of Figure 5.
Open the supply circuit and adjust to the required pressure.
Measure the flow rate when a stable and continous flow is established.
NOTE The test may be carried out for various values of supply pressure. In this case, draw the flow rate graph as a function of pressure and use it to calculate the value of the flow rate at 0.3 MPa (3 bar).
8.2 Evaluation of the shape of flow
8.2.1 For flow rate regulators without aeration At the regulator outlet, the flow shall basically be along the axis of the regulator and shall flow continously over a length of 150 mm at the nominal flow rate for each class: it shall be neither flattened nor constricted, nor scattered to such an extent that splashing results. It shall remain compact in a pressure zone between 0,05 MPa (0,5 bar) and 0,5 MPa (5 bar).
8.2.2 For flow rate regulators with aeration At a dynamic pressure of 0,3 MPa (3 bar) the flow shall be regular and compact and visually shall exhibit regular and adequate aeration over a length of 150 mm. It shall remain full and aerated in a pressure zone between 0,05 MPa (0,5 bar) and 0,5 MPa (5 bar).
For these minimum flow rates, the minimum air intake shall be:
2,78 x 10 1/s (around 10 1/h).
8.3.2 Test method for measuring air flow
8.3.2.1 Assembly
The test assembly shall be as shown in Figure 8.
8.3.2.2 Procedure
Fit the grille cage of the aerator into the appropriate device 5.
Open the water supply circuit and adjust the flow to the value corresponding to the class of aerator (Table 6).
Measure the air flow using flowmeter 6, once a stable, continuous flow has been established.
Verify that the requirements comply with subclause 8.3.1.
9 Acoustic properties
9.1 Requirements
At 0,3 MPa (3 bar) the flow rate regulators should correspond to one of the following requirements:
D  30 dB(A)
Lap 15 dB(A)
9.2 Test method
9.2.1 Assembly
Identical to that in subclause 8.1.2.1.
9.2.2 Procedure
The tests are carried out at a pressure of 0,3 MPa (3 bar), in accordance with standard Iso 3822-1 and ISO 3822-4.
10 Marking
All flow rate regulators shall be marked indelibly with the following on their outer face:
— the name or mark of the manufacturer
— indication of the flow rate class.
The indication of the flow rate class shall be marked on the outer face of the skirt of the grille cage, if this is detachable.
10.1 Flow rate regulator without air intake In order to distinguish them from aerators, flow rate regulators without air intake shall also be marked with an X visible from the outside.
10.2 Swivel flow rate regulator
The marking shall be both on the swivel device and on the regulator.