ISO 6182-8:2006
(Main)Fire protection — Automatic sprinkler systems — Part 8: Requirements and test methods for pre-action dry alarm valves
Fire protection — Automatic sprinkler systems — Part 8: Requirements and test methods for pre-action dry alarm valves
ISO 6182-8:2006 specifies performance requirements, methods of test and marking requirements for pre-action dry alarm valves and manufacturers' specified relevant trim used in non-interlock pre-action automatic fire protection systems. Performance and test requirements for other auxiliary components or attachments to pre-action dry valves are not covered by ISO 6182-8:2006.
Protection contre l'incendie — Systèmes d'extinction automatique du type sprinkler — Partie 8: Exigences et méthodes d'essai des postes de préalarme sous air
General Information
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Standards Content (Sample)
INTERNATIONAL ISO
STANDARD 6182-8
First edition
2006-03-01
Fire protection — Automatic sprinkler
systems —
Part 8:
Requirements and test methods
for pre-action dry alarm valves
Protection contre l'incendie — Systèmes d'extinction automatique du
type sprinkler —
Partie 8: Exigences et méthodes d'essai des postes de préalarme sous
air
Reference number
ISO 6182-8:2006(E)
©
ISO 2006
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ISO 6182-8:2006(E)
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ISO 6182-8:2006(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions. 1
4 Requirements . 5
5 Production testing and quality control. 13
6 Tests. 13
7 Marking . 20
8 Instruction chart and trim . 21
Bibliography . 22
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ISO 6182-8:2006(E)
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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 6182-8 was prepared by Technical Committee ISO/TC 21, Equipment for fire protection and fire fighting,
Subcommittee SC 5, Fixed firefighting systems using water.
ISO 6182 consists of the following parts, under the general title Fire protection — Automatic sprinkler systems:
⎯ Part 1: Requirements and test methods for sprinklers
⎯ Part 2: Requirements and test methods for wet alarm valves, retard chambers and water motor alarms
⎯ Part 3: Requirements and test methods for dry pipe valves
⎯ Part 4: Requirements and test methods for quick-opening devices
⎯ Part 5: Requirements and test methods for deluge valves
⎯ Part 6: Requirements and test methods for check valves
⎯ Part 7: Requirements and test methods for early suppression fast response (ESFR) sprinklers
⎯ Part 8: Requirements and test methods for pre-action dry alarm valves
⎯ Part 9: Requirements and test methods for water mist nozzles
⎯ Part 10: Requirements and test methods for domestic sprinklers
⎯ Part 11: Requirements and test methods for pipe hangers
⎯ Part 12: Requirements and test methods for grooved end pipe couplings
⎯ Part 13: Requirements and test methods for extended coverage sprinklers
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ISO 6182-8:2006(E)
Introduction
This part of ISO 6182 is one of a number of ISO International Standards prepared by ISO/TC 21 covering
components for automatic sprinkler systems, including the following:
a) carbon dioxide systems (ISO 6183),
b) explosion suppression systems (ISO 6184),
An International Standard covering foam systems is planned.
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INTERNATIONAL STANDARD ISO 6182-8:2006(E)
Fire protection — Automatic sprinkler systems —
Part 8:
Requirements and test methods for pre-action dry alarm valves
1 Scope
This part of ISO 6182 specifies performance requirements, methods of test and marking requirements for
pre-action dry alarm valves and manufacturers’ specified relevant trim used in non-interlock pre-action
automatic fire protection systems. (See 3.24 for the principle modes of operation of pre-action dry alarm
valves.)
Performance and test requirements for other auxiliary components or attachments to pre-action dry valves are
not covered by this part of ISO 6182.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 7-1, Pipe threads where pressure-tight joints are made on the threads — Part 1: Designation, dimensions
and tolerances
ISO 37, Rubber, vulcanized or thermoplastic — Determination of tensile stress-strain properties
ISO 188, Rubber, vulcanized or thermoplastic — Accelerated ageing and heat resistance tests
ISO 898–1, Mechanical properties of fasteners made of carbon steel and alloy steel — Part 1: Bolts, screws
and studs
ISO 898–2, Mechanical properties of fasteners — Part 2: Nuts with specified proof load values — Coarse
thread
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
alarm device
mechanical or electrical device to sound an alarm upon operation of the valve
3.2
anti-reseat latch
mechanical device that prevents the sealing assembly from returning to its closed position after operation
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ISO 6182-8:2006(E)
3.3
automatic drain valve
normally open device that automatically drains water from and vents the intermediate chamber of a valve to
the atmosphere when the valve is in the ready position, and limits water flow from the chamber after the valve
has tripped
3.4
auxiliary pressure
pressure acting against an auxiliary diaphragm or piston, taken from either the service pressure or an external
source
3.5
clapper
type of sealing element
NOTE See 3.20.
3.6
corrosion-resistant material
1)
bronze, brass, Monel metal, austenitic stainless steel, or equivalent, or plastic material conforming with the
requirements of this document
3.7
differential
ratio of service pressure to system air pressure (expressed as gauge pressures) at the trip point
NOTE See 3.24.
3.8
differential-type valve
type of valve in which air pressure in the system acts directly and/or indirectly on the sealing assembly to
maintain it in the closed position
NOTE The air seat of the sealing assembly is of equal or larger diameter than the diameter of the water seat of the
sealing assembly, with the two separated by an intermediate chamber maintained at atmospheric pressure.
3.9
flow velocity
speed of water flow through a valve, expressed as the equivalent water velocity through a pipe of the same
nominal size as the valve
3.10
intermediate chamber
that part of a valve which separates the air and/or water sealing assembly seating surfaces and is at
atmospheric pressure when the valve is in the ready condition
3.11
leak point
system air pressure for a specific service pressure at which water begins to flow from the intermediate
chamber, automatic drain valve or alarm connection
3.12
mechanical-type valve
type of valve in which the air pressure in the system acts on the sealing assembly and linking mechanism to
maintain it in the closed position
1) Monel is an example of a suitable product available commercially. This information is given for the convenience of
users of this part of ISO 6182 and does not constitute an endorsement by ISO of this product.
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ISO 6182-8:2006(E)
3.13
non-interlock pre-action system
automatic fire protection system in which water is admitted to the system upon either activation of a
supplemental detection system or loss of system pressure in combination with failure of the detection system
3.14
pre-action system
automatic fire protection system using a valve which is operated by an auxiliary means to admit water into a
system of automatic sprinklers or nozzles, as shown in Figure 1
Figure 1 — Operational flow chart for pre-action system
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ISO 6182-8:2006(E)
3.15
pre-action dry alarm valve
valve of the check type in which air pressure in the sprinkler system prevents water from filling the system
NOTE Fire detection of auxiliary means causes automatic operation of the pre-action dry alarm valve. If there is any
failure of the auxiliary means, the pre-action dry alarm valve shall operate as a dry valve (see ISO 6182-3).
3.16
priming water
water used to seal a sealing assembly and prevent cementation of working parts
3.17
rated working pressure
maximum service pressure at which a valve is intended to operate
3.18
ready condition
set condition
state of a valve with the sealing assembly in the closed and set position with service and system pressure
applied
3.19
reinforced elastomeric element
element of clapper, clapper assembly or seat seals in a composite of an elastomeric compound with one or
more other components
3.20
sealing assembly
main movable sealing element (such as a clapper) of the valve which prevents the reverse flow of air and
which maintains air pressure in the system piping
3.21
sealing assembly seat ring
main fixed sealing element of a valve which prevents the reverse flow of water and which maintains air
pressure in the system piping
3.22
service pressure
static water pressure at the inlet to a valve when the valve is in the ready condition
3.23
system pressure
pressure at the main outlet of a valve when the valve is in the ready condition
3.24
system air pressure
static air pressure in the system piping when the valve is in the ready condition
3.25
trim
external equipment and pipework, excluding the main installation pipework, fitted to valve installation
assembly
3.26
trip point
point at which a valve operates, admitting water into the system, measured in terms of the system air pressure
at a given service pressure
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ISO 6182-8:2006(E)
3.27
water-motor alarm
hydraulically actuated device which provides a local audible alarm as a result of a flow through a valve
3.28
water-motor transmitter
hydraulically actuated device which generates an electrical current for a remote alarm as a result of operation
of the valve
4 Requirements
4.1 Nominal sizes
The nominal size of a valve shall be the nominal diameter of the inlet and outlet connections, i.e. the pipe size
for which the connections are intended. The sizes shall be 40 mm, 50 mm, 65 mm, 80 mm, 100 mm, 125 mm,
150 mm, 200 mm, or 250 mm. The diameter of the waterway through the sealing assembly seat ring may be
less than the nominal size.
4.2 Connections
4.2.1 All connections shall be designed for use at the rated working pressure of the valve.
4.2.2 The dimensions of all connections shall conform with the applicable requirements of International
Standards. If International Standards are not applicable, national standards shall be permitted to be used.
4.2.3 An opening not smaller than 15 mm nominal diameter shall be provided for an alarm line connection.
4.2.4 If priming water is required to seal the downstream side of the sealing assembly, an external means
shall be provided to introduce the priming water.
4.2.5 Means shall be provided to prevent water columning and to check the level of priming water (if
required).
4.2.6 Suitable means shall be provided to facilitate testing of alarms without tripping the valve.
4.2.7 Valves shall be provided with a means of sounding an alarm if water enters the downstream piping to
an elevation exceeding 0,5 m above the sealing assembly unless the valve is provided with an automatic
means for drainage.
4.2.8 For differential-type valves, suitable means shall be provided to vent water from the intermediate
chamber and to prevent a partial vacuum between the upstream and downstream sealing elements of the
sealing assembly.
4.3 Rated working pressure
4.3.1 The rated working pressure shall be not less than 1,2 MPa (12 bar).
4.3.2 Inlet and outlet connections may be machined for lower working pressures to match installation
equipment provided the valve is marked with the lower working pressure. See 7.3 f).
4.4 Body and cover
4.4.1 The body and cover shall be made of a material having corrosion resistance at least equivalent to cast
iron.
4.4.2 Cover fasteners shall be made of steel, stainless steel, titanium, or other materials with equivalent
physical and mechanical properties.
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ISO 6182-8:2006(E)
4.4.3 If non-metallic materials, other than gaskets, and seals or metals with a melting point less than 800 °C
form part of the body or cover, the valve assembly shall be subjected to a fire exposure test as specified in 6.9.
Following the fire exposure test, the sealing assembly shall open freely and fully and the valve shall withstand
a hydrostatic pressure test as specified in 6.7.1 without permanent deformation or failure.
4.4.4 It shall not be possible to assemble the valve with the cover plate in a position which either improperly
indicates flow direction or prevents proper operation of the valve.
4.5 Strength
4.5.1 An assembled valve, with the sealing assembly blocked open, shall withstand, without rupture, an
internal hydrostatic pressure of four times the rated working pressure for a period of 5 min when tested as
specified in 6.7.1.
4.5.2 If the test in accordance with 6.9 is not done with standard production fasteners, the supplier shall
provide documentation showing that the calculated design load of any fastener, neglecting the force required
to compress the gasket, shall not exceed the minimum tensile strength specified in ISO 898-1 and ISO 898-2
when the valve is pressurized to four times the rated working pressure. The area of the application of pressure
shall be calculated as follows:
a) If a full-face gasket is used, the area of application of pressure is that extending out to a line defined by
the inner edge of the bolts.
b) If an “O”-ring seal or ring gasket is used, the area of application of force is that extending out to the
centreline of the “O”-ring or gasket.
4.6 Access for maintenance
Means shall be provided to permit access to working parts and removal of the sealing assembly. Any method
adopted should permit ready maintenance by one person with a minimum of down time.
4.7 Components
4.7.1 Any component that is normally disassembled during servicing shall be designed so that it can not be
reassembled improperly without providing an external visual indication when the valve is returned to service.
4.7.2 With the exception of valve seats, all parts intended for field replacement shall be capable of being
disassembled and reassembled using tools normally employed by the trade.
4.7.3 All components shall be non-detachable during normal operation of the valve.
4.7.4 Failure of the sealing assembly diaphragms or seals shall not prevent the valve from opening.
4.7.5 Sealing surfaces of sealing assemblies shall have corrosion resistance equivalent to bronze and have
sufficient width of surface contact to withstand ordinary wear and tear, rough usage, compression stresses
and damage due to pipe scale or foreign matter carried by the water.
4.7.6 Springs and diaphragms shall not fracture or rupture during 5 000 cycles of normal operation when
tested in accordance with 6.2.
4.7.7 There shall be no sign, on visual examination, of damage to the sealing assembly after testing for the
operational requirements of 4.14 in accordance with 6.10 and 6.12.
4.7.8 When wide open, the sealing assembly shall bear against a definite stop. The point of contact shall be
located so that impact or the reaction of the water flow does not permanently twist, bend or fracture valve
parts.
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ISO 6182-8:2006(E)
4.7.9 Where rotation or sliding motion is required, the part or its bearing shall be made of a corrosion-
resistant material. Materials lacking corrosion resistance shall be fitted with bushings, inserts or other parts
made of corrosion-resistant materials at those points where freedom of movement is required
4.7.10 A valve having a differential ratio of the sealing assembly exceeding of 1,16-to-1 for a service
pressure range of 0,14 MPa to 1,2 MPa (1,4 bar to 12 bar) shall be provided with an anti-reseat latch that
prevents the valve from resetting automatically. The valve shall require manual means to return the valve to
the ready (set) condition. It shall not be possible to return the valve to the ready (set) condition before draining
the pipework.
4.7.11 A valve having a differential ratio of 1,16-to-1 or less over a service pressure range of 0,14 MPa to
1,2 MPa (1,4 bar to 12 bar) shall be provided with means to prevent the valve from automatically returning to
the ready (set) condition and to permit draining of the pipework after the valve has tripped. Manual or external
means shall be provided to return the valve to the ready (set) condition.
4.8 Leakage
4.8.1 There shall be no leakage, permanent distortion or rupture of a valve when an internal pressure of
twice the rated working pressure is applied for 5 min with the sealing assembly open when tested in
accordance with 6.7.1.
4.8.2 No leakage shall be permitted across the sealing assembly into the intermediate chamber or into the
alarm port when tested in accordance with 6.7.2. There shall be no leakage, permanent distortion or rupture of
a valve at an internal pressure of twice the rated working pressure applied to the upstream side of the sealing
assembly for 2 h with the downstream end pressurized in accordance with 6.7.2.
4.8.3 Mechanical type valves shall show no signs of leakage, permanent distortion or structural failure when
subjected to an internal hydrostatic pressure of twice the rated working pressure applied for a period of 2 h to
the upstream end of the valve with the sealing assembly closed and the downstream end vented in
accordance with 6.7.3. Following this test, the valve shall operate in accordance with 4.14 when tested once in
accordance with 6.10.2.2 at a service pressure of 0,2 MPa (2 bar).
4.8.4 Valves fitted with a latch shall withstand, without leakage, permanent distortion or structural failure, an
internal hydrostatic pressure of twice the maximum air pressure specified by the manufacturer for a period of
5 min applied to the downstream side of the valve with the sealing assembly closed and the upstream end
vented in accordance with 6.7.4. Following this test, the valve shall operate in accordance with 4.14 when
tested once in accordance with 6.10.2.2 at a service pressure of 0,2 MPa (2 bar).
4.8.5 Valves not fitted with a latch shall withstand, without leakage, permanent distortion or structural failure,
an internal hydrostatic pressure of twice the rated working pressure for a period of 5 min applied to the
downstream side of the valve with the sealing assembly closed and the upstream end vented in accordance
with 6.7.5. Following this test, the valve shall operate in accordance with 4.14 when tested once in accordance
with 6.10.2.2 at a service pressure of 0,2 MPa (2 bar).
4.9 Non-metallic components (excluding gaskets, diaphragms, seals and other elastomeric
parts)
4.9.1 Non-metallic valve parts that affect proper valve function shall be subjected to the applicable ageing of
its non-metallic parts as described in 6.4 and 6.5 using separate sets of samples, as applicable. After ageing,
a valve shall meet the requirements of 4.8, 4.13 and 4.14.4 when tested in accordance with the applicable
tests described in 6.6, 6.8 and 6.11.
4.9.2 There shall be no cracking, warping, creep, or other signs of deterioration that can preclude proper
operation of the valve.
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ISO 6182-8:2006(E)
4.10 Sealing assembly elements
4.10.1 A seal made of elastomeric or other resilient materials shall not adhere to the mating surface when
tested in accordance with 6.3.1. Where the same design of seat is used for more than one size of valve, it
shall be permitted to test only the size with the highest stress on the seating surface.
4.10.2 Any non-reinforced elastomer forming the seal shall have the following properties when tested in
accordance with 6.3.2 and the appropriate sections of ISO 37:
a) maximum set of 5 mm when 25 mm long marks are stretched to 75 mm, held for 2 min, and measured
2 min after release;
b) either
1) minimum tensile strength 10 MPa (100 bar) and minimum ultimate elongation 300 % (25 mm to
100 mm); or
2) minimum tensile strength 15 MPa (150 bar) and minimum ultimate elongation 200 % (25 mm to
75 mm);
c) after exposure to oxygen for 96 h at (70 + 1,5) °C and 2,0 MPa (20 bar), the tensile strength and ultimate
elongation shall not be less than 70 % of the corresponding properties of specimens which have not been
heated in oxygen, and any change in hardness shall not be greater than 5 type-A durometer units;
d) after immersion in distilled water for 70 h at (97,5 + 2,5) °C, the tensile strength and ultimate elongation
shall not be less than 70 % of the corresponding properties of specimens which have not been heated in
water and the change in volume of the specimens shall be not greater than 20 %.
4.10.3 A reinforced elastomeric sealing element shall be capable of being flexed without cracking or breaking
and shall have a change in volumetric expansion not greater than 20 % when tested in accordance with 6.3.3.
4.10.4 Sealing surfaces shall prevent leakage of water into the alarm port when the valve is tested in the
ready position in accordance with 6.10.
4.10.5 For a composite of an elastomeric compound with one ore more other components, the tensile
strength of the combination shall be at least twice that of the elastomeric material alone.
4.11 Clearances
4.11.1 The radial clearance between a hinged sealing assembly and the inside walls in every position except
wide open shall not be less than 12 mm for cast iron bodies and shall not be less than 6 mm if the body and
sealing assembly are of cast iron or steel with corrosion protective coatings tested in accordance with 6.14,
non-ferrous material, stainless steel or materials having equivalent physical, mechanical and corrosion
resistant properties. See Figure 2 a).
4.11.2 There shall be a diametrical clearance of not less than 6 mm between the inner edges of a seat ring
and the metal parts of a hinged sealing assembly when the valve is in the closed position. See Figure 2 b).
4.11.3 Any space in which the sealing assembly can trap debris beyond the seat shall be not less than 3 mm
deep.
4.11.4 The diametrical clearance (D − D ) between hinge pins and their bearings shall be not less than
2 1
0,125 mm. See Figure 2 b).
4.11.5 The total axial clearance between the clapper hinge and adjacent valve body bearing (L − L )
2 1
surfaces shall be not less than 0,25 mm. See Figure 2 c).
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ISO 6182-8:2006(E)
a) Radial clearance, C = R − R b) Diametrical clearance, C = D − D
R 2 1 D 2 1
c) Total axial clearance, C
TA
C = L − L ; Clearance A = (L − L )/2
TA 2 1 3 2
Figure 2 (continued)
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ISO 6182-8:2006(E)
d) Inside bushing dimensions
C = L − L
TA 2 4
Clearance A = (L − L )/2 + (L − L )/2
3 2 4 1
Key
1 valve body
2 pin
3 sealing assembly
4 bushings
Figure 2 — Clearance
4.11.6 Any reciprocating guide components which are essential to allow a valve to open shall have a
minimum diametrical clearance of not less than 0,7 mm in that portion over which the moving component
enters the fixed component and of not less than 0,05 mm in that portion of the moving component
continuously in contact with the fixed component in the ready (set) position.
4.11.7 Sealing assembly guide bushings or hinge-pin bearings shall project a sufficient axial distance to
maintain not less than 1,5 mm (Clearance A) clearance between ferrous metal parts. See Figure 2 d).
Clearance less than 1,5 mm shall be permitted where adjacent parts are of bronze, brass, Monel metal,
austenitic stainless steel, titanium or similar corrosion resistant materials. When corrosion resistance of steel
parts is provided by a protective coating, the parts shall show no visible signs of deterioration of the coating,
such as blistering, delamination, flaking or increased resistance to movement when tested in accordance with
6.14.
4.12 Hydraulic friction loss
The maximum pressure loss across the valve at the appropriate flow given in Table 1, as tested by the
method of 6.6, shall not exceed 0,08 MPa (0,8 bar). If the pressure loss exceeds 0,02 MPa (0,2 bar), the
pressure loss shall be marked on the valve. See 7.3 j).
4.13 Endurance
The valve and its moving parts shall show no sign of distortion, cracks, loosening, separation or other sign of
failure, following 30 min of water flow in accordance with 6.11.
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ISO 6182-8:2006(E)
Table 1 — Required flow rates for pressure drop determination
Nominal size Flow rate
mm l/min
40 300
50 470
65 800
80 1 200
100 1 880
125 2 940
150 4 240
200 7 540
250 11 780
300 21 200
4.14 Operational performance
4.14.1 A pre-action dry alarm valve with associated trim shall operate and provide an indication of operation
by actuating mechanical and/or electrical alarm devices at any service pressure within the range of 0,14 MPa
(1,4 bar) to the rated working pressure and at a minimum flow rate of 300 l/min, when tested in accordance
with 6.7.2 a). The alarm devices shall sound for more than 50 % of the time for all flow conditions below
0,2 MPa (2 bar) and continuously for all flow conditions at higher pressures.
4.14.2 A pre-action dry alarm valve with associated trim shall not operate when the pre-action dry valve is in
pre-action mode
...
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