Wood preservatives - Determination of the relative protective effectiveness of a wood preservative for use under a coating and exposed out-of-ground contact - Field test: L-joint method

This European standard specifies a method for determining the relative protective effectiveness against fungal decay of a wood preservative applied to wood, which is subsequently surface coated, and exposed out of contact with the ground. The method is applicable to the testing of commercial or experimental preservatives applied to non-durable timbers by methods appropriate to commercial practice and subsequently overcoated with a specified coating system. The method is applicable to products and processes used individually or in combination to prevent the development of the decay in wood

Holzschutzmittel - Bestimmung der relativen Wirksamkeit eines Holzschutzmittels zur Anwendung unter einem Anstrich und ohne Erdkontakt - Freilandprüfung: L-Verbindungsmethode

Diese Europäische Norm legt ein Verfahren zur Bestimmung der Wirksamkeit eines Schutzmittels gegen Pilzbefall fest, das an Holz angewendet wird, welches anschließend mit einem Oberflächenanstrich versehen und ohne Erdkontakt der Witterung ausgesetzt wird. Die Wirksamkeit wird im Verhältnis zu einer Behandlung mit einem Vergleichsmaterial bewertet.
Das Verfahren ist für die Prüfung kommerzieller oder experimenteller Holzschutzmittel anwendbar, die mit für die kommerzielle Praxis geeigneten Verfahren in nicht dauerhafte Hölzer eingebracht und nachfolgend mit einem angegebenen Anstrichsystem überstrichen werden. Das Verfahren ist für Produkte und Verfahren anwendbar, die einzeln oder in Kombination eingesetzt werden, um das Entstehen von Fäulnis im Holz zu verhindern.
Das Verfahren ist ebenfalls für industrielle Beschichtungssysteme anwendbar, die auch Holz schützende Substanzen enthalten.

Produits de préservation du bois - Détermination de l’efficacité protectrice d’un produit de préservation du bois pour employ un revetment et hors de contact avec le sol - Essais de champ: méthode avec un esemblage en L

La présente Norme européenne spécifie une méthode permettant de déterminer l'efficacité protectrice relative contre la pourriture provoquée par les champignons d'un système de protection comprenant l'application du produit de préservation sur le bois, puis l'application d'un revêtement de surface, le bois étant exposé aux intempéries et hors de contact avec le sol. L'efficacité est évaluée par rapport à un produit de préservation du bois de référence.
La méthode s'applique à l'essai des produits de préservation commerciaux ou expérimentaux appliqués sur des bois non durables par des méthodes appropriées couramment utilisées dans la pratique, puis recouverts d'un système de finition spécifié. La méthode s'applique aux produits et aux procédés mis en oeuvre individuellement ou conjointement afin d'empêcher le développement de la pourriture dans le bois.
La méthode est également appropriée pour les systèmes de finition en usine pour lesquels une protection et une préservation du bois sont revendiquées.

Zaščitna sredstva za les - Terenska preskusna metoda za ugotavljanje relativne preventivne učinkovitosti zaščitnega sredstva za les, ki je pokrit in ni v stiku z zemljo – Terenski preskus: metoda vezi L

Ta evropski standard določa metodo za ugotavljanje relativne preventivne učinkovitosti zaščitnega sredstva pred plesnobo na lesu, katerega površina je bila naknadno premazana in ni v stiku z zemljo. Metoda se uporablja za testiranje komercialnih ali eksperimentalnih zaščitnih sredstev za neobstojni les z metodami, ki ustrezajo poslovni praksi. Les se naknadno prekrije s specifičnim premaznim sistemom. Ta metoda se uporablja za izdelke in postopke, ki se uporabljajo posamezno ali v kombinaciji, za preprečitev razpadanja lesa.

General Information

Status
Published
Public Enquiry End Date
29-Apr-2012
Publication Date
03-Dec-2014
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
18-Nov-2014
Due Date
23-Jan-2015
Completion Date
04-Dec-2014

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2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Holzschutzmittel - Bestimmung der relativen Wirksamkeit eines Holzschutzmittels zur Anwendung unter einem Anstrich und ohne Erdkontakt - Freilandprüfung: L-VerbindungsmethodeProduits de préservation du bois - Détermination de l’efficacité protectrice d’un produit de préservation du bois pour employ un revetment et hors de contact avec le sol - Essais de champ: méthode avec un esemblage en LWood preservatives - Determination of the relative protective effectiveness of a wood preservative for use under a coating and exposed out-of-ground contact - Field test: L-joint method71.100.50Wood-protecting chemicalsICS:Ta slovenski standard je istoveten z:EN 330:2014SIST EN 330:2015en,fr,de01-januar-2015SIST EN 330:2015SLOVENSKI
STANDARDSIST EN 330:20041DGRPHãþD



SIST EN 330:2015



EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 330
November 2014 ICS 71.100.50 Supersedes EN 330:1993English Version
Wood preservatives - Determination of the relative protective effectiveness of a wood preservative for use under a coating and exposed out-of-ground contact - Field test: L-joint method
Produits de préservation du bois - Détermination de l'efficacité protectrice d'un produit de préservation du bois pour emploi sous un revêtement et hors de contact avec le sol - Essai de champ: méthode avec un assemblage en L
Holzschutzmittel - Bestimmung der relativen Wirksamkeit eines Holzschutzmittels zur Anwendung unter einem Anstrich und ohne Erdkontakt - Freilandprüfung: L-Verbindungsmethode This European Standard was approved by CEN on 30 August 2014.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre:
Avenue Marnix 17,
B-1000 Brussels © 2014 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 330:2014 ESIST EN 330:2015



EN 330:2014 (E) 2 Contents Page Foreword .4 Introduction .5 1 Scope .6 2 Normative references .6 3 Terms and definitions .6 4 Principle .6 5 Materials .7 5.1 End-seal compounds .7 5.2 Reference coating .7 5.3 Reference preservative .7 5.4 Wood test specimens .7 6 Apparatus and Equipment . 10 6.1 Wood working equipment . 10 6.2 Conditioning area . 10 6.3 Application equipment . 10 6.4 Balance . 10 6.5 Safety equipment and protective clothing . 10 6.6 Labels / tags . 10 6.7 Exposure site . 11 6.8 Weathering racks . 11 7 Sampling . 11 8 Treatment and handling of test L-joints . 12 8.1 General . 12 8.2 End-sealing . 12 8.3 Process . 12 8.4 Retention of preservative . 12 8.5 Post-treatment handling of the L-joints . 12 9 Reference L-joints. 13 10 Untreated test control L-joints . 14 11 Exposure test site . 14 11.1 Number of test sites . 14 11.2 Installation of the L-joints at the test site . 14 12 Inspections . 14 12.1 L-joints for non- destructive inspection . 14 12.2 L-joints for destructive inspection . 15 13 Evaluation . 16 13.1 General . 16 13.2 Assessment of decay . 16 14 Duration of the test . 17 15 Validity of the test . 17 16 Test report . 17 SIST EN 330:2015



EN 330:2014 (E) 3 Annex A (informative)
Flow chart for the preparation and exposure of L-joints for test . 19 Annex B (informative)
Information on treatment processes, reference and alternative preservatives and materials . 20 Annex C (informative)
Example of a Test Report. 22 Annex D (informative)
Environmental, health and safety precautions within chemical / biological laboratory . 24 Bibliography . 25
SIST EN 330:2015



EN 330:2014 (E) 4 Foreword This document (EN 330:2014) has been prepared by Technical Committee CEN/TC 38 “Durability of wood and wood-based products”, the secretariat of which is held by AFNOR. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by May 2015 and conflicting national standards shall be withdrawn at the latest by May 2015. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights. This document supersedes EN 330:1993. Compared to EN 330:1993 the following changes have been made: — The scope of the standard clarifies that the effectiveness is evaluated to a reference material; — The grading system for the assessment of decay has been modified in Table1; — Modifications have been made to the duration (Clause 14) and validity (Clause 15) of the test; — In Annex B information has been added that the reference wood preservatives stated in the document may only be used for research purposes in accordance with the Biocidal Products Regulations (Regulation (EU) No. 528/2012); — An informative Annex D covering environmental, health and safety precautions has been added. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. SIST EN 330:2015



EN 330:2014 (E) 5 Introduction This European Standard describes a method of test for wood preservatives that are intended for use under a surface coating in timber to be exposed to the weather and out of contact with the ground (Use Class 3, EN 335). The main objective of the test is to evaluate the relative effectiveness of the preservative applied to jointed samples of Pinus sylvestris L sapwood by a treatment technique relevant to its intended practical use. Effectiveness is evaluated relative to a reference material. The method is concerned with protection against attack by the complete sequence of microorganisms occurring under natural conditions, including those basidiomycete fungi that eventually cause decay. It takes into account the effects of weathering (light, rain and heat) on the effectiveness of a wood preservative under a coating. The method does not accelerate the rate of decay (see Note), however the coating failure occurs immediately at the test start, that is even sooner than in badly designed and poorly maintained joinery exposed under the same conditions. The method may be used, after modification, for other purposes including evaluating the effectiveness of a test preservative as follows: — in protecting timbers of a different wood species; — under different types of coating. Since the L-joints are exposed to natural outdoor conditions during the test period, variations in test conditions from one location to another have to be expected. Differences in climate, especially rainfall, will influence the general rate of development of decay fungi. However, by comparing the results obtained for the test preservative with those obtained with the reference material and with those for untreated, control L-joints, the relative protective effectiveness of the preservative under test can be evaluated. NOTE The coating is intended to make the technique relevant to the end use – albeit the test pieces are badly maintained and designed in order to accelerate the test. SIST EN 330:2015



EN 330:2014 (E) 6 1 Scope This European Standard specifies a method for determining the relative protective effectiveness against fungal decay of a wood preservative applied to wood in combination with a subsequent surface coating, exposed to the weather and out of contact with the ground. The effectiveness is evaluated relative to a reference wood preservative. The method is applicable to the testing of commercial or experimental preservatives applied to non-durable timbers by methods appropriate to commercial practice and subsequently coated with a specified coating system. The method is applicable to products and processes used individually or in combination to prevent the development of decay in the wood. The method is also appropriate for factory finishing systems which include wood protection and wood preservation claims. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 1001-2, Durability of wood and wood based products - Terminology - Part 2: Vocabulary EN 335, Durability of wood and wood-based products - Use classes: definitions, application to solid wood and wood-based products 3 Terms and definitions For the purposes of this document, the terms and definitions given in EN 1001-2 apply. 4 Principle Jointed samples (L-joints) are treated, assembled, coated and placed out of contact with the ground and exposed to the normal environmental and ecological factors which affect coated wood so exposed in practice. The organisms that colonize such units invade in their natural sequence of moulds, blue stain fungi, soft rot fungi and basidiomycetes. Colonization by basidiomycetes, as shown by the presence of visible decay, is assessed at least annually by visual inspection of the L-joints after they have been dismantled. In addition, periodically, sets of samples are examined after dismantling and sawing along the grain of the L-joint assemblies to reveal their internal condition. These data are compared with those generated using a reference material and untreated samples to assess relative performance. It is recommended that the replicates for non-destructive inspection continue to be exposed beyond the minimum 5 year period, preferably until failure. NOTE Inspection after sawing is necessary because application by processes such as double vacuum and superficial (surface) application does not result in complete penetration of the L-joint members. The untreated core of the samples, therefore, can show internal decay before it becomes visible on the surface within the joint. SIST EN 330:2015



EN 330:2014 (E) 7 5 Materials 5.1 End-seal compounds 5.1.1 Preservative resistant end-seal A material resistant to the penetration of the reference and test preservative solutions (or separate materials for each). 5.1.2 Weatherproof end-seal A material that prevents water entry into the test specimen and remains effective for the duration of exposure of the test specimen to the weather. NOTE Two coats of an epoxy-resin / pitch compound have been found to be suitable. 5.2 Reference coating Opaque high gloss, gloss or semi-gloss solvent borne alkyd paint applied in 2 or 3 coats to give a dry film build of (50 ± 5) µm or an opaque water borne acrylic paint applied in 1 or 2 coats to give a dry film build of 110 µm -120 µm when measured by method 4A (microscope method) of ISO 2808. If a particular coating system is specified by the supplier of the test preservative to be an integral part of the protection system, this shall be used in conjunction with the test preservative, instead of the reference coating. Details of the coating system used shall be given in the test report including the number of coats and the contribution each coat makes to the coating system used, e.g. primer function. 5.3 Reference preservative Containing hexabutyldistannoxane (bis(tri-n-butyltin) oxide) as the active ingredient and with the following composition: — Hexabutyldistannoxane
minimum mass fraction of 1 % (mass fraction 95 % active ingredient); — Aliphatic neutral hydrocarbon resin mass fraction of 5 %; — Hydrocarbon solvent mass fraction of 94 %, (distillation range 160 °C to 215 °C; aromatic content mass fraction < 17 %). If an alternative wood preservative product is used the concentration of the product used should provide a performance equivalent to the specified concentration of the reference wood preservatives referred to in this standard. Evidence of equivalence shall be recorded in the test report. NOTE See informative Annex B on alternative reference preservatives. 5.4 Wood test specimens 5.4.1 Wood species Sapwood of Pinus sylvestris (Scots Pine, redwood) shall be used. Some heartwood is permitted in the mortise member but none in the joint area (5.4.3). SIST EN 330:2015



EN 330:2014 (E) 8 Optionally, other wood species may be chosen that are in use or proposed for exterior use. They should include a hardwood if the preservative is expected to be used in hardwoods, for example beech (Fagus sylvatica L). Specimens should be cut exclusively from sapwood or heartwood. 5.4.2 Quality of wood Use sound, straight-grained wood without knots. Material of a resinous appearance shall be avoided. Use wood with between 2,5 annual growth rings per 10 mm and 8 annual growth rings per 10 mm in the case of Scots pine sapwood. The proportion of latewood in the annual rings shall not exceed 30 % of the whole for Scots pine sapwood. The wood shall not have been floated, stored in water, or heated above 60 °C or treated with chemical agents. If additional wood species are used, the density and the number of annual rings for each species should be recorded in the report. 5.4.3 Preparation of test specimens Use equipment capable of achieving and maintaining the condition of the timber stock at a moisture content of (12 ± 2) % mass fraction). Prepare sticks of cross-section (38 ± 1) mm x (38 ± 1) mm by sawing and planing the timber (5.4.1) with the grain parallel to the long axis and annual rings aligned parallel with one lateral face. This requirement can be relaxed for timber to be used to prepare the mortises. A moisture meter of the two-pronged conductivity type is suitable for assessing moisture content. The L-joint is prepared as two members (Figure 1) both (203 ± 1) mm long. The tenon members shall be cut from the most accurately prepared and orientated sticks and the mortise members from the remaining material. The joint region shall be free from any minor defects. Heartwood up to 20 % of the cross-section is permitted in the mortise member of sapwood specimens, except within the joint and heartwood shall not exceed 20 % at any point in the cross-section. Machine the joints to the dimensions given in Figure 1, with a tolerance such that the two members provide a firm, but not tight, push-fit. Align the tenons and the mortises at 90° to the annual rings (Figure 1). Round the longitudinal edges of the tenon members exposed during the test to a radius of 2 mm, (Figure 1). Store the L-joints in the conditioning area (6.2) until required for treating. SIST EN 330:2015



EN 330:2014 (E) 9 Dimensions in millimetres
Key 1 heartwood permitted 2 label position 3 mortise member 4 tenon member (note rounding of the longitudinal edges) Tolerances in the joint: a)
c) 13 ± 1 d) f)
b) 12 ± 1 e) The two members shall provide a firm but not tight push-fit. Figure 1 — The L-joint SIST EN 330:2015



EN 330:2014 (E) 10 5.4.4 Number of L-joints The specimens are divided into: a) L1 – L-joints for non-destructive visual inspection (at least 5 years’ exposure) To obtain the maximum information from the test specimens should be retained on the rack and inspected annually until failure. Prepare at least 10 replicate L joints for each combination of test parameters (wood species (5.4.1), test preservative, reference L- joints (Clause 9), untreated controls (Clause 10) and coating system (5.2). b) L2 – L-joints for destructive visual inspection Prepare at least 10 for each combination of test parameters. NOTE 1 This allows 5 replicates for sampling at each of two exposure periods. NOTE 2 It is normally necessary to treat a higher number of replicates so that the required number can be selected after treatment (see 8.3) and the inclusion of specimens achieving abnormally high or low retention of preservative avoided. 5.4.5 Labelling of L-joints Individual members of L-joints shall be assigned unique identification numbers in such a way that these numbers are retained through all preparation operations. After application of coatings, a durable identification label or tag (6.6) shall be affixed to each L-joint. 6 Apparatus and Equipment 6.1 Wood working equipment A machine saw capable of producing a fine-sawn finish and equipment capable of producing planed timber. 6.2 Conditioning area Well ventilated, controlled at (20 ± 2) °C and (65 ± 5) % relative humidity. 6.3 Application equipment Suitable equipment should be available for treating the test and reference specimens. 6.4 Balance Laboratory balance, capable of weighing test specimens to the nearest 0,1 g. 6.5 Safety equipment and protective clothing Appropriate for the test product and the reference preservative, to ensure the safety of the operator. 6.6 Labels / tags Use inert, durable labels / tags and corrosion-resistant fixing pins. SIST EN 330:2015



EN 330:2014 (E) 11 6.7 Exposure site Select a test site that produces Use Class 3 conditions according to EN 335. Avoid areas that are exposed to extremes of local environmental influences, especially industrial pollution. 6.8 Weathering racks L-shaped racks facing the prevailing weather, approximately 900 mm above ground level, 500 mm above any low vegetation (short grass is acceptable), sloping back at 10° and made of durable materials. The racks shall be provided with slots or holes to prevent the collection of water in the angle of the rack. The racks shall be provided with stickers of a durable non-reactive material, for example silicon spacers or Pinus sylvestris heartwood, cross-section minimum 5 mm x 5 mm, maximum 10 mm x 10 mm, to separate the tenon member of the L -joint from the rack, and with spacing pieces affixed to the back, to separate the L -joints and to maintain their orientation. The cross-section of a suitable exposure rack is shown in Figure 2. Position the racks to face the prevailing weather. In most of the European area this would normally be in a southwest direction. The orientation shall be stated in the test report. Dimensions in millimetres
Key 1 spacing piece 2 back of rack 3 rack of durable material e.g. Douglas fir plywood 4 stickers of a durable material (see 6.8) Figure 2 — L-joint during exposure 7 Sampling The sample of preservative shall be representative of the product to be tested. If a particular coating is specified by the preservative supplier as an integral part of the protection system the sample used shall be representative of the coating system to be tested. Samples shall be stored and handled in accordance with any written requirements from the supplier. SIST EN 330:2015



EN 330:2014 (E) 12 For the sampling of preservatives from bulk supplies, the procedures given in EN 212 should be used. It is recommended to chemically identify the active ingredients content. 8 Treatment and handling of test L-joints 8.1 General The sequence of operations involved in the preparation and exposure of the L-joints is summarized in informative Annex A. 8.2 End-sealing Remove the L-joints from the conditioning chamber and using adequate equipment to reach and maintain the (12 ± 2) % moisture content of the wood (see 5.4.3). Seal the end of the tenon members (but not the mortise members) remote from the joint with the preservative-resistant end sealing compound (see 5.1.1), and allow to dry. 8.3 Process Determine and record the volume of each of the L-joint members and the mass to the nearest 0,1 g. Apply the test preservative to the test L-joints using the process specified by the supplier of the preservative/protection system. NOTE 1 A range of model treatment processes is given in informative Annex B. NOTE 2 For development products it is preferable to test more than one retention value, ideally three; ranged around that thought to be appropriate for use out of ground contact. The concentration or retention (X) may be achieved by varying the concentration of active ingredient(s) in the formulation. Alternatively, the parameters of the treatment process can be altered. A suitable range of retentions could be 0.5X 1.0X, and 2.0X. A narrower range can be used if the capability of the product is sufficiently well known, for example, use a geometrical series with a factor of √2. 8.4 Retention of preservative Weigh the L-joint members before treatment. After treatment, the excess of solution on the surface of the L-joint members shall be allowed to drip off or be removed with a cloth. Reweigh each member immediately and record the mass after treatment to the nearest 0,1 g. Calculate the uptake of preservative solution for each member and express it in kilograms of preservative per cubic metre of wood for penetrating processes, and in grams of preservative per square metre of wood for superficial application methods. Reject any L-joint member with retentions deviating by more than 10 % from the mean for that type of member and substitute an appropriate alternative specimen (see Note 2 to 5.4.4) which falls within this range. NOTE Although the retention for penetrating processes is calculated as kg/m3 for the whole volume of the joint, not all penetrating processes will be designed to treat the full cross section. The supplier may wish extra joints to be included so an analysis can be made of the preservative retention to a specified penetration depth. 8.5 Post-treatment handling of the L-joints 8.5.1 Conditioning the L joint members Condition the L-joints treated with test preservative in accordance with the supplier’s instructions for its use. SIST EN 330:2015



EN 330:2014 (E) 13 Where no instructions are provided by the preservative supplier or where L-joints treated with a reference preservative are to be conditioned the following approach shall be used: Condition the treated L-joint members in a well-ventilated, covered area protected from rain and frost. Ensure free ventilation by storing members horizontally on supporting racks made of a material that does not react with the preservative. Condition the L-joint members for 14 d. 8.5.2 Coating Assemble the L-joints (5.4.3). Apply the reference coating to all lateral faces of the L-joints and allow them to dry. Do not coat the exposed end grain at the assembled joint. Where a specific coating system is required by the supplier (see 5.2), the L-joints treated with the test preservative are treated with this coating system instead of the reference coating. If the test is to be exposed for the minimum 5-year period, it is not necessary to maintain the coating. If the test is to be exposed beyond 5 years, then the coating on the replicates for non-destructive visual inspection (L1) should be maintained in accordance with the supplier’s instructions. Following such maintenance, the joint should be separated (8.5.5) before the L-joints are returned to the racks. Details of maintenance should be included in the test report. 8.5.3 Labelling Ensure permanent labels (6.6) are affixed to the mortise member, well away from the joint area, and positioned so that they can be read when the L-joints are in positio
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