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SIST EN 975-1:2009
01-julij-2009
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SIST EN 975-1:2003
SIST EN 975-1:2003/A1:2003
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Sawn timber - Appearance grading of hardwoods - Part 1: Oak and beech
Schnittholz - Sortierung nach dem Aussehen von Laubholz - Teil 1: Eiche und Buche
Bois sciés - Classement d'aspect des bois feuillus - Partie 1: Chene et hetre
Ta slovenski standard je istoveten z: EN 975-1:2009
ICS:
79.040 Les, hlodovina in žagan les Wood, sawlogs and sawn
timber
SIST EN 975-1:2009 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN 975-1:2009
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SIST EN 975-1:2009
EUROPEAN STANDARD
EN 975-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
March 2009
ICS 79.040 Supersedes EN 975-1:1995
English Version
Sawn timber - Appearance grading of hardwoods - Part 1: Oak
and beech
Bois sciés - Classement d'aspect des bois feuillus - Partie Schnittholz - Sortierung nach dem Aussehen von Laubholz
1: Chêne et hêtre - Teil 1: Eiche und Buche
This European Standard was approved by CEN on 24 January 2009.
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 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 Management Centre has the same status as the
official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2009 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 975-1:2009: E
worldwide for CEN national Members.
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SIST EN 975-1:2009
EN 975-1:2009 (E)
Contents Page
Foreword .3
1 Scope .4
2 Normative references .4
3 Terms and definitions .5
4 Method of determination of sawn timber quality .5
4.1 Rules for grading .5
4.2 Grading principles .6
4.2.1 Assessment of the quality .6
4.2.2 Cases of un-edged boards .6
4.3 Criteria to be taken into account .6
4.3.1 General .6
4.3.2 Criteria linked to the structure of the timber .7
4.3.3 Sawing characteristics .7
4.3.4 Warp .7
4.3.5 Fungal and insect attacks .7
4.3.6 Stains .7
4.3.7 Other characteristics .8
5 Denomination of grades .8
5.1 General .8
5.2 Oak (Q) .8
5.3 Beech (F) .9
6 Acceptance of batches .9
6.1 Un-edged boards .9
6.2 Square edged timber .9
7 Grading rules .9
7.1 Grading face .9
7.2 Un-edged boards .9
7.2.1 Grading area .9
7.2.2 Presence of a solitary feature (only one) . 10
7.3 Strips and square edged timber . 10
7.3.1 Knots . 10
7.3.2 Other features . 10
7.4 Baulks . 10
7.5 Appearance grading Tables . 11
Bibliography . 35
2
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SIST EN 975-1:2009
EN 975-1:2009 (E)
Foreword
This document (EN 975-1:2009) has been prepared by Technical Committee CEN/TC 175 “Round and sawn
timber”, 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 September 2009, and conflicting national standards shall be
withdrawn at the latest by September 2009.
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 975-1:1995.
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, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
3
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SIST EN 975-1:2009
EN 975-1:2009 (E)
1 Scope
This European Standard specifies the rules determining the quality of appearance graded sawn timber. It
describes various grades of temperate hardwood rough sawn timber and regularized timber for which it lays
down denominations and definitions. It also gives rules for composition and acceptance of batches.
This standard gives minimum requirements for each grade classification. Sawn timber not included within
limits given in this standard may be defined, if necessary, by contract specifications established on the basis
of this standard.
This standard applies to grading of green and dried timber. Characteristics apply at the time of grading.
This standard does not apply to the strength grading of structural timber or to sawn timber for pallets.
This standard is applicable to the following products:
a) Oak sawn timber, in the following categories:
1) Un-edged boards: individual selected pieces and boules;
2) Square edged timber and strips (not exceeding 41 mm thickness);
3) Baulks (sum of thickness + width ≥ 200 mm and thickness ≥ 80 mm).
b) Beech sawn timber, in the following categories:
1) Un-edged boards: individual selected pieces and boules;
2) Square edged timber and strips;
3) Prepared timber (dried timber).
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.
EN 844-1:1995, Round and sawn timber – Terminology – Part 1: General terms common to round timber and
sawn timber
EN 844-3:1995, Round and sawn timber – Terminology – Part 3: General terms relating to sawn timber
EN 844-4:1997, Round and sawn timber – Terminology – Part 4: Terms relating to moisture content
EN 844-6:1997, Round and sawn timber – Terminology – Part 6: Terms relating to dimensions of sawn timber
EN 844-7:1997, Round and sawn timber – Terminology – Part 7: Terms relating to anatomical structure of
timber
EN 844-9:1997, Round and sawn timber – Terminology – Part 9: Terms relating to features of sawn timber
EN 844-10:1998, Round and sawn timber – Terminology – Part 10: Terms relating to stain and fungal attack
EN 844-11:1998, Round and sawn timber – Terminology – Part 11: Terms relating to degrade by insects
4
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SIST EN 975-1:2009
EN 975-1:2009 (E)
EN 844-12:2000, Round and sawn timber – Terminology – Part 12: Additional terms and general index
EN 1310, Round and sawn timber – Method of measurement of features
EN 1311, Round and sawn timber – Method of measurement of biological degrade
EN 1313-2, Round and sawn timber – Permitted deviations and preferred sizes – Part 2: Hardwood sawn
timber
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 844-1:1995, EN 844-3:1995,
EN 844-4:1997, EN 844-6:1997, EN 844-7:1997, EN 844-9:1997, EN 844-10:1998, EN 844-11:1998 and
EN 844-12:2000 and the following apply.
3.1
dried timber
timber with a stipulated reduced moisture content
3.2
green timber
timber that has not been dried to or below the fibre saturation point
NOTE Green timber has a moisture content normally above 30 %.
[EN 844-4:1997]
3.3
width or length reduction
notional decrease in the actual dimensions of a board to exclude features that may subsequently be removed
4 Method of determination of sawn timber quality
4.1 Rules for grading
Hardwood (oak and beech) can be put into grades using the principles laid down in 4.2, the criteria defined in
4.3 and the following tables:
Table 2 gives rules for grading oak un-edged boards;
Table 3 gives rules for grading oak strips and square edged timber;
Table 4 gives rules for grading oak baulks;
Table 5 gives rules for grading beech un-edged boards;
Table 6 gives rules for grading beech strips and square edged timber;
Table 7 gives rules for grading beech prepared timber.
5
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SIST EN 975-1:2009
EN 975-1:2009 (E)
4.2 Grading principles
4.2.1 Assessment of the quality
For individual selected boards and boules grading is made on the faces. For other pieces grading is made on
faces and edges. The size, position and frequency of features, sawing defects and deteriorations are taken
into account. Non-conformity with the conditions applicable to any one of these elements is sufficient to
downgrade the piece.
Dimensional variation is not taken into account for quality grading of the pieces. It is already covered by
EN 1313-2 or by any specific requirements defined contractually.
Only the following categories can be reduced in width and/or length:
Individual selected boards,
boules.
4.2.2 Cases of un-edged boards
4.2.2.1 Individual selected boards
No more than 10% of pieces one grade lower than the lowest one stated for the batch is allowed. For mixed
grade batches the minimum proportion of each grade shall be identified.
4.2.2.2 Boules
Recognising the characteristics inherent in a growing tree, a boule may comprise a number of un-edged
boards of different grades.
Proportion of grades allowed within a boule is given in Table 1:
Table 1 — Proportion of grades allowed within one boule
Stated grade
≥ 65%
< 25% One grade lower
Two grades lower
< 10%
Pieces presenting features which are not in conformity with the boule grade shall be graded in accordance
with reduced width rules (see 3.2).
4.3 Criteria to be taken into account
4.3.1 General
Quality is determined on the basis of the rules in tables given in this standard and measurement rules
according to EN 1310 and EN 1311.
The moisture content of the timber at the time of grading shall be stated.
The following criteria are sufficient for the appearance grading:
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SIST EN 975-1:2009
EN 975-1:2009 (E)
4.3.2 Criteria linked to the structure of the timber
Knots (size, nature, degree of intergrowth, frequency);
Shakes and checks;
Slope of grain;
Bark-pocket;
Sapwood (for oak); unless specified in the contract, sound sapwood is permitted without limit in all
grades;
NOTE Unsound sapwood is considered according to grading criteria given in Tables of Clause 7.
Included sapwood.
4.3.3 Sawing characteristics
Boxed heart;
Exposed pith;
NOTE Presence of pith on un-edged boards is not a qualitative element for downgrading but width reduction may be
considered.
Wane.
4.3.4 Warp
Bow;
Spring;
Cup;
Twist.
4.3.5 Fungal and insect attacks
4.3.6 Stains
Red heart (in beech);
Black streaks;
Dote;
Rot;
Brown oak;
Other discolorations.
7
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SIST EN 975-1:2009
EN 975-1:2009 (E)
4.3.7 Other characteristics
Characteristics as texture, grain, quarter and plain sawn timber are not taken into account in the grading.
5 Denomination of grades
5.1 General
The denomination includes from three to six characters.
5.1.1 The first character is the species' initial in Latin:
Q for oak;
F for beech.
5.1.2 The next character indicates the type of product:
B for boules;
S for individual selected boards;
F for strips and square edged timber;
P for baulks;
D for prepared timber.
5.1.3 The next character indicated the quality grade
"A" indicates exceptional quality;
1, 2 , etc. represent the other grades.
In some cases, these are subdivided, denoted by the addition of lower case letters and suffixes (see below).
The grades for oak and beech are specified in 5.2 and 5.3.
5.2 Oak (Q)
Boules Q-BA – Q-B1 – Q-B2 – Q-B3 – Q-B4
Individual selected boards Q-SA – Q-S1 – Q-S2 – Q-S3 – Q-S4
Strips and square edged timber Q-F1a – Q-F1b – Q-F2 – Q-F3 – Q-F4
Baulks Q-PA – Q-P1 – Q-P2
For strips and square edged timber, the addition, at the end of class denomination:
Of the letter X indicates the presence of sapwood on one face of strips or square edged pieces in limit
given by Table 3,
Of letters XX indicates the presence of sapwood on all faces and edges of strips or square edged pieces
if it is over the limit given by Table 3.
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SIST EN 975-1:2009
EN 975-1:2009 (E)
5.3 Beech (F)
Boules F-BA – F-B1 – F-B2 – F-B3
Individual selected boards F-SA – F-S1 – F-S2 – F-S3
Strips and squared edged timber F-F1 – F-F2 – F-F3
Prepared timber F-DA – F-D1 – F-D2
The addition of the letter R at the end indicated the presence of red heart.
6 Acceptance of batches
6.1 Un-edged boards
Unless otherwise specified by the purchase, reception with quality acceptance of individual selected un-edged
boards and boules shall take place on the seller's premises to allow width or length reduction to be carried out
if necessary (see 4.2.2).
6.2 Square edged timber
Reception can be carried out either on the seller's or the buyer's premises, as mutually agreed, using random
sampling method given in CEN/TS 12169.
7 Grading rules
7.1 Grading face
a) For individual selected un-edged boards
Take into account features which are on the "falling" face, which is defined as the face which is visible on the
production line, after sawing.
In the case of specific measurement, the quality is determined by the face, the width of which is measured.
b) For boules
Take into account features which are on the upper face in the stacking position to form the boule.
c) For strips and square edged timber
Take into account features which are on the best face.
7.2 Un-edged boards
7.2.1 Grading area
A notional area of 0,2m x 2,0 m containing the maximum number or the largest features on the grading face
determines the grade of each board.
Features located less than 10 cm from edges or ends of un-edged boards are not considered, unless the
resulting width and length is insufficient to inscribe in an area of 0,20 m x 2 m. This manner of doing is not
valid for Q-BA and Q-SA classes; only width reduction can be used and it is limited to 1/3 of the width.
9
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SIST EN 975-1:2009
EN 975-1:2009 (E)
7.2.2 Presence of a solitary feature (only one)
Un-edged boards cannot be downgraded by the presence of only one feature which is not accepted in a
grading. Consequently, this feature is accepted with a width or length reduction.
7.3 Strips and square edged timber
7.3.1 Knots
Take into account knots in the most penalized linear metre or the whole piece if the length is < 1 m.
Equivalence concept, except for Q-F1a. This allows any repartition of knots, providing:
each knot diameter is under maximum allowed diameter;
the sum of diameters is below the maximum permitted.
Example for QF-2:
the maximum allowed diameter of knot is 25 mm;
the maximum number is 3, so the sum is 75 mm (25 mm x 3).
One possible repartition is 4 knots of 10 mm, 1 knot of 15 mm and 1 knot of 20 mm.
7.3.2 Other features
These features are taken into account on the whole piece.
7.4 Baulks
Take into account features on the whole piece, except for dead knots where the maximum number is
determined by linear metre.
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SIST EN 975-1:2009
EN 975-1:2009 (E)
7.5 Appearance grading Tables
Table 2 — Appearance grading of oak un-edged boards
GRADE
Dimensional
Q-B A and Q-S A Q-B 1and Q-S 1 Q-B 2 and Q-S 2 Q-B 3and Q-S 3 Q-B 4 and Q-S 4
Characteristics
Minimum acceptable for Minimum acceptable for Minimum acceptable for Minimum acceptable for Minimum acceptable for
grade grade grade grade grade
Length
2 m and more
Narrowest width 100 mm excluding sapwood 80 mm excluding sapwood 60 mm excluding sapwood measured at the mid-length of the
120 mm excluding sapwood
on the entire length of the measured at the mid-length of measured at the mid-length of loose un-edged timber
piece the loose un-edged timber the loose un-edged timber
11
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SIST EN 975-1:2009
EN 975-1:2009 (E)
Table 2 — Appearance grading of oak un-edged boards (continued)
GRADE
Features (reminding : Grading area of 0,2 m x 2,0 m)
Q-B A and Q-S A Q-B 1and Q-S 1 Q-B 2 and Q-S 2 Q-B 3and Q-S 3 Q-B 4 and Q-S 4
Maximum acceptable for Maximum acceptable for Maximum acceptable for Maximum acceptable for Maximum acceptable for
grade grade grade grade grade
Sound, intergrown or Only one of size < 20 mm Permitted
Knots < 5 mm : maximum 8 Knots < 5 mm : not limited Knots < 10 mm : not limited
partially intergrown
Max diameter : 25 mm Max diameter : 40 mm Max diameter : 70 mm
knots
Sum of knots from 5 mm to Sum of knots from 5 mm to 40 Sum of knots from 10 mm to
25 mm < 50 mm mm < 100 mm 70 mm < 160 mm
a a a
Not intergrown, dead
Not permitted 1 of 25 mm with reduction 1 of 40 mm with reduction 1 of 70 mm with reduction Permitted
or rotten knots
Solitary knots 15% of the width of the piece 20% of the width of the piece 25% of the width of the piece 30% of the width of the piece Permitted
a a a a
with reduction with reduction with reduction with width reduction
a
Heart shake
Permitted with width reduction Permitted with width reduction Permitted Permitted
a
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SIST EN 975-1:2009
EN 975-1:2009 (E)
Table 2— Appearance grading of oak un-edged boards (continued)
GRADE
Features (reminding : Grading area of 0,2 m x 2,0 m)
Q-B A and Q-S A Q-B 1 and Q-S 1 Q-B 2 and Q-S 2 Q-B 3 and Q-S 3 Q-B 4 and Q-S 4
Maximum acceptable for Maximum acceptable for Maximum acceptable for Maximum acceptable for Maximum acceptable for
grade grade grade grade grade
Ring shakes and frost
Not permitted Permitted with reduction max Permitted with reduction max Permitted with reduction Permitted
crack 1/5 of width 1/3 of width
a a a
Straight shakes
Permitted with reduction if the Permitted with reduction Permitted with reduction Permitted Permitted
length of shakes is < width of
the board a a
Oblique shakes
single Not permitted Permitted with reduction if the Permitted with width reduction Permitted with reduction Permitted
length of shakes is < width of
a
the board
multiple Permitted with length
Not permitted Permited with length reduction Permitted with reduction Permitted
reduction
Spiral grain Permitted with maximum slope No limitation unless specified No limitation unless specified No limits unless specified No limits
of 8 %
Slope of grain
No limitation unless specified No limitation unless specified No limitation unless specified No limitation unless specified No limitation unless specified
13
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SIST EN 975-1:2009
EN 975-1:2009 (E)
Table 2— Appearance grading of oak un-edged boards (continued)
GRADE
Features (reminding : Grading area of 0,2 m x 2,0 m)
Q-B A and Q-S A Q-B 1 and Q-S 1 Q-B 2 and Q-S 2 Q-B 3 and Q-S 3 Q-B 4 and Q-S 4
Maximum acceptable for Maximum acceptable for Maximum acceptable for Maximum acceptable for Maximum acceptable for
grade grade grade grade grade
a
Bark pocket
Not permitted Permitted if solitary with reduction Permitted Permitted
Unsound sapwood
Not permitted Permitted
a
Permitted if solitary with width reduction
Included sapwood Not permitted Permitted with width reduction Permitted
a
c
brown streak
Not permitted Permitted with length Permitted with length Permitted Permitted
c c
reduction reduction
b a
Brown heart Not permitted 25 % of the width with a width reduction Permitted
a
Rot Not permitted Not permitted Permitted if solitary with a reduction Permitted
a
Insect attack in Permitted with width reduction Permitted with width reduction Permitted
sapwood a
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SIST EN 975-1:2009
EN 975-1:2009 (E)
Table 2— Appearance grading of oak un-edged boards (concluded)
GRADE
Features (reminding : Grading area of 0,2 m x 2,0 m)
Q-B A and Q-S A Q-B 1 and Q-S 1 Q-B 2 and Q-S 2 Q-B 3 and Q-S 3 Q-B 4 and Q-S 4
Maximum acceptable for Maximum acceptable for Maximum acceptable for Maximum acceptable for Maximum acceptable for
grade grade grade grade grade
a
Insect attack in heart
Not permitted Permitted on edges with width reduction for QB-1 Permitted
wood
a
Permitted with length or/and width reduction for QB-2 and Q-B3
a
Generally, the length and/or width reduction shall be agreed between buyer and seller.
b
Sawn timber with values above limit values are traded under the denomination "brown oak".
c
Localized natural colour variation need not necessarily be considered as downgrade where it is not related to decay in the wood.
15
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SIST EN 975-1:2009
EN 975-1:2009 (E)
Table 3 — Appearance grading of oak strips and square edged timber
GRADE
Features (reminding : Grading area of 0,2 m x 2,0 m)
Q-F 1a Q-F 1b Q-F 2 Q-F 3 Q-F 4
(3 to 4 clear faces)
Maximum acceptable Maximum acceptable Maximum acceptable for Maximum acceptable for Maximum acceptable
for grade for grade grade grade for grade
Sound, intergrown or For Width < 120 mm, Knots with diameters < 5 Knots with diameters < 5 mm Knots with diameters < 10 mm
partially intergrown
mm are not taken into are not taken into account are not taken into account.
knots account.
1 knot of 10 mm 70 mm
For Width < 120 mm, For Width < 120 mm,
For Width < 120 mm,
for width ≥ 120 mm No restriction providing the
appearance and integrity of
3 knots of 12 mm the piece are suitable for
2 knots of 10 mm
3 knots of 25 mm 3 knots of 40 mm its intended purposes.
a
20% of pieces may have
a a
one more sound knot of 10
mm on the surface. For Width ≥ 120 mm
1 extra knot permitted in
each additional 40 mm of
for Width ≥ 120 mm for Width ≥ 120 mm
width.
1 extra knot permitted in each 1 extra knot permitted in each
additional 40 mm of width additional 40 mm of width
Dead and rotten knots Not permitted Not permitted Not permitted 1 of 20mm 1 of 35 mm
1 of 20 mm
Check
Not permitted Not permitted Permitted Permitted Permitted
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SIST EN 975-1:2009
EN 975-1:2009 (E)
Table 3 — Appearance grading of oak strips and square edged timber (continued)
GRADE
Features (reminding : Grading area of 0,2 m x 2,0 m)
Q-F 1a Q-F 1b Q-F 2 Q-F 3 Q-F 4
(3 to 4 clear faces)
Maximum acceptable Maximum acceptable for Maximum Maximum acceptable Maximum acceptable
for grade grade acceptable for grade for grade for grade
Shake Not permitted Not permitted Not permitted Up to 20% of pieces Length of the shake up to
permitted with the length of the width of the piece
the shake no more than the
width of piece
Slope of grain
3 % Without restriction Without restriction Without restriction Without restriction
Bark pocket
Not permitted Not permitted Not permitted Not permitted Permitted
Black streak
Not permitted Up to 10 % of the pieces Up to 20% of the pieces Permitted Permitted
Brown heart
Not permitted Not permitted Not permitted Not permitted Permitted
Brown streak
Not permitted Not permitted Not permitted Up to 10 % of the pieces Permitted
Rot
Not permitted Not permitted Not permitted Not permitted Not permitted
Insect attacks
Not permitted Not permitted Not permitted Not permitted Not permitted
Boxed heart
Not permitted Not permitted Not permitted Not permitted Permitted
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SIST EN 975-1:2009
EN 975-1:2009 (E)
Table 3 — Appearance grading of oak strips and square edged timber (continued)
GRADE
Features (reminding : Grading area of 0,2 m x 2,0 m)
Q-F 1a Q-F 1b Q-F 2 Q-F 3 Q-F 4
(3 to 4 clear faces)
Maximum acceptable Maximum acceptable Maximum acceptable Maximum acceptable for Maximum acceptable for
for grade for grade for grade grade grade
Exposed pith Not permitted Not permitted Not permitted Not permitted Permitted
Wane Not permitted Not permitted Not permitted Up to 3 mm on face and on Up to 10 % of the width and up to
edge 20 % of the length
Deformations (bow,
2mm/m of length 5mm/m
...