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[CCMC 12627-R] CCMC Canadian code compliance evaluation

From: National Research Council Canada

In most jurisdictions this document is sufficient evidence for approval by Canadian authorities.

Learn more about CCMC recognition Look for the trusted CCMC mark on products to verify compliance.

Code compliance opinion

It is the opinion of the Canadian Construction Materials Centre that the evaluated product, when used as structural composite lumber (SCL) in accordance with the conditions and limitations stated in this evaluation, complies with the following code:

National Building Code of Canada 2015

ID Code provision Solution type
04-03-01-01-00-0- Buildings and their structural members m ...Acceptable
09-23-02-02-00-0- Ends of wood joists, beams and other mem ...Alternative
09-23-04-02-00-0- Spans for built-up wood and glued-lamina ...Alternative
09-23-10-01-00-0- The size and spacing of studs shall conf ...Alternative

Ontario Building Code

Ruling No. 05-19-143 (12627-R) authorizing the use of this product in Ontario, subject to the terms and conditions contained in the Ruling, was made by the Minister of Municipal Affairs and Housing on 2006-01-31 (revised 2010-02-17) pursuant to s.29 of the Building Code Act, 1992 (see Ruling for terms and conditions). This Ruling is subject to periodic revisions and updates.

The above opinion is based on the evaluation by the CCMC of technical evidence provided by the evaluation holder, and is bound by the stated conditions and limitations. For the benefit of the user, a summary of the technical information that forms the basis of this evaluation has been included.

Product information

Product name

TimberStrand® LSL

Product description

The product is laminated strand lumber (LSL), which is a structural composite lumber manufactured from strands of wood species or species combinations blended with an isocyanate-based binder adhesive. The wood species, species combinations and binder adhesive used are as specified in the Weyerhaeuser “TimberStrand® LSL Manufacturing Standards.” The strands are oriented parallel to the length of the member. The mats are pressed to the required thickness using a steam injection press. The product is available in thicknesses up to 140 mm, depths up to 1 220 mm and lengths up to 14.63 m.

The product is treated with zinc borate and may be used within the building envelope (i.e., protected assemblies) as sill plates over masonry or concrete foundations, footings or slabs.

Independent, third-party quality assurance monitoring and inspection is conducted by PFS Corporation, Los Angeles, CA and/or by Intertek Testing Services NA Ltd., Coquitlam, BC.

The permitted design values are outlined in the Technical information section.

Isometric view of the product

Figure 1. Product details for TimberStrand® LSL

Manufacturing plant

This evaluation is valid only for products produced at the following plant:

Product nameManufacturing plant
Kenora, ON, CA
TimberStrand® LSLProduct evaluated by the CCMC

Product evaluated by the CCMC Indicates that the product from this manufacturing facility has been evaluated by the CCMC

  Conditions and limitations

The CCMC’s compliance opinion is bound by this product being used in accordance with the conditions and limitations set out below.


  • The product, as with all SCL, is intended for dry service applications only.Footnote (1)
  • The product is intended for use in construction as an alternative material to lumber. Proprietary design values presented for the product are to be used by professional engineers for design in accordance with CSA O86-14 for structural applications such as beams, headers, joists, rafters, studs and columns as intended by the product manufacturer. The specific application must be qualified through testing and validated by the manufacturer. Applications such as I-joist flanges and metal-plated truss chords are beyond the scope of this evaluation.
  • The product is treated with zinc borate and may be used within the building envelope as sill plates over masonry or concrete foundations, footings or slabs (AWPA Use Category UC2) as long as the product is not in contact with the ground, but may be subjected to dampness.
  • The product is considered equivalent to sawn lumber floor joists with respect to its fire-resistance rating for equivalent member size and spacing within a rated floor assembly, including the wood floor assemblies in Table, Fire and Sound Resistance of Floors, Ceilings and Roofs, of Division B of the NBC 2015. The product may also be considered equivalent to sawn lumber for use as a fire-stop material.
  • See Appendix B for conditions and limitations for use of the product as studs in shear walls.
  • The pre-engineered tables in the literature below have been provided to the CCMC by Weyerhaeuser to demonstrate compliance with Part 9, Housing and Small Buildings, of the NBC 2015 for acceptance by the local authority having jurisdiction (AHJ):



    1. Weyerhaeuser’s pre-engineered tablesFootnote (2)

      When the product is used to support uniform loads only, the installation must be in accordance with the tables and installation details published in the documents by Weyerhaeuser entitled:

      1. “Beams, Headers, and Columns (TJ-9505) (Limit States Design for Western Canada),” July 2016;
      2. “Beams, Headers, and Columns (TJ-9500) (Limit States Design for Eastern Canada),” October 2017; and
      3. “Select Beam Design Tables (TB-354),” February 2019.

      When TimberStrand® LSL (32 mm thickness) is used as a rim board supporting uniform loads only, the installation must be in accordance with the information and details contained in:

      1. “Technical Bulletin for 1-1/4” Rim Board, TimberStrand LSL (2542).”Footnote (3)

      Except where a floor is required to support a concentrated load or a specified unfactored live load in excess of 1.9 kN/m2, and in lieu of engineering design, the spans for the product when used as floor joists, rafters and beams may conform to the spans for Select Structural Grade for the Douglas Fir – Larch (D Fir – L) group in Span Tables to of the NBC 2015. Maximum deflections must conform to Subsection 9.4.3., Deflections, of Division B of the NBC 2015. Floor joists must be designed to meet the deflection and vibration set in the NBC 2015 for lumber.

      The product must be installed in accordance with Weyerhaeuser’s installation guidelines noted in the above-mentioned documents for those applications falling within the scope of the documents. Applications outside the scope of these installation guidelines require engineering on a case-by-case basis.

    2. Weyerhaeuser’s installation details

      Weyerhaeuser’s pre-engineered details within the documents identified as (1), (2) and (3) outlined in i. above are limited in scope to building designs where the anticipated loads on the following structural details are not exceeded:


      • floor and/or snow (plf) tables (pages 6–7 of (2), page 5 of (1));
      • beam installation details (page 12 of (2), page 10 of (1));
      • nails installed on the narrow face (page 13 of (2), page 11 of (1));
      • allowable holes in beams (page 14 of (2), page 12 of (1));
      • tapered end cuts (page 15 of (2), page 13 of (1));
      • multiple-member connections for side-loaded beams (pages 16–17 of (2), pages 14–15 of (1));
      • multiple-member connections for top-loaded beams (page 18 of (2), page 16 of (1));
      • rim board installation details (page 2 of (4)); and
      • vertical load resistance (page 3 of (4));
    3. Engineering required

      When required by the AHJ or for structural applications beyond the scope/limitations of the above-referenced Weyerhaeuser publications, the drawings or related documents must bear the authorized seal of a professional engineer (or other certified authority approved by the AHJ) who is skilled in wood design and licensed to practice under the appropriate provincial or territorial legislation.

      Installations beyond the scope/limitations of Sections i. and ii. imply, but are not limited to, the following:

      • higher loads/longer spans than the manufacturer’s pre-engineered details;
      • concentrated loads;
      • areas of high wind or high seismicity;
      • design of supporting members/columns when the total beam/header load exceeds the NBC 2015 pre-engineered beam/lintel tables; and
      • design of supporting foundation footings when the total load exceeds the NBC 2015 pre-engineered floor/roof joist tables.

      The engineer must design in accordance with CSA O86-14 and may consult the “Engineering Guide for Wood-Frame Construction,” published by the Canadian Wood Council.

      The specified strengths for the product must not exceed the values set forth in the Technical information section of this evaluation. See Figure 2 for strand orientation with respect to loading.

      The factored resistances of rim board product are shown in Table 4.

      The ends of all product members used as joists, rafters and beams must be restrained to prevent rollover. This is normally achieved by attaching a diaphragm sheathing to the top or to the compression edge, and to an end wall or shear transfer panel capable of transferring a minimum unfactored uniform load of 730 N/m or the required shear forces due to wind or seismic conditions. Blocking or cross-bracing with equivalent strength may also be used.

      The compression edges of all product members used as joists, rafters and beams must be laterally supported at least every 610 mm, except where designed in accordance with CSA O86-14.

      Nailing of the product perpendicular to the wide face of strand (WFS) must conform to Table, Nailing of Framing, of Division B of the NBC 2015. Edge nailing of the product parallel to the WFS must conform to Table 2.

    4. Engineering support provided by manufacturer

      Weyerhaeuser may provide engineering services in conjunction with Weyerhaeuser product specification and offers the following support contact number for its Canadian offices: 888-453-8358.

  • This product must be identified with the phrase “CCMC 12627-R” along its side. This CCMC number is only valid when it appears in conjunction with the WH-ETL certification mark of Intertek Testing Services and/or the mark of PFS Corporation. In addition, because the product is treated with zinc borate it must be further identified with the designations: “STRANDGUARD” and “AWPA UC2.”

  Technical information

This evaluation is based on demonstrated conformance with the following criteria:

Evaluation requirements
Criteria number Criteria name
CCMC-TG-061710-15BCCMC Technical Guide for Structural Composite Lumber

The evaluation holder has submitted technical documentation for the CCMC’s evaluation. Testing was conducted at laboratories recognized by the CCMC. The corresponding technical evidence for this product is summarized below.

Design requirements
Table 1. TimberStrand® LSL specified strengths (MPa)Footnote (1) Footnote (2) Footnote (7)
Grade Modulus of elasticity (MOE) Axial – tension parallel to grain FtFootnote (3) Axial – compression parallel to grain Fc Joist or beamFootnote (1) – flexure FbFootnote (4) Footnote (5) Joist or beamFootnote (1) – shear Fv Joist or beamFootnote (1) – compression perpendicular to grain Fcperp PlankFootnote (1) – flexure FbFootnote (6) PlankFootnote (1) – shear Fc PlankFootnote (1) – compression perpendicular to grain Fcperp
1.30E 8 965 13.70 20.21 21.65 5.39 8.92 24.20 1.95 7.92Footnote (12)
1.35E 9 310 15.05 20.94 23.41 5.66 9.39 26.19 1.95 8.27
1.40E 9 655 16.40 21.68 25.18 5.93 9.87 28.18 1.95 8.62
1.45E 9 995 17.75 22.41 26.94 6.19 10.34 30.16 1.95 8.98
1.50E 10 345 19.10 23.14 28.70 6.46 10.81 32.15 1.95 9.33
1.55E 10 685 20.40 23.88 29.60 6.73 11.28 33.30 1.95 9.69
1.60E 11 030 21.65 24.61 30.90 7.00 11.75 34.40 1.95 10.04Footnote (13)
1.65E 11 375 22.45 25.35 32.03 7.27 12.23 35.68 1.95 10.39
1.70E 11 720 23.25Footnote (8) 26.08 33.15 7.54 12.70 36.95 1.95 10.75
1.75E 12 065 24.29 26.82 34.66 7.81 13.17 38.70 1.95 11.10
1.80E 12 410 25.33 27.55Footnote (9) 36.18 8.07Footnote (10) 13.64Footnote (11) 40.45 1.95 11.45
1.85E 12 755 26.36 27.55Footnote (9) 37.69 8.07Footnote (10) 13.64Footnote (11) 42.20 1.95 11.81
1.90E 13 100 27.40 27.55Footnote (9) 39.20 8.07Footnote (10) 13.64Footnote (11) 43.95 1.95 12.16
1.95E 13 445 28.51 27.55Footnote (9) 40.55 8.07Footnote (10) 13.64Footnote (11) 45.46 1.95 12.52
2.00E 13 790 29.63 27.55Footnote (9) 41.90 8.07Footnote (10) 13.64Footnote (11) 46.98 1.95 12.87
2.05E 14 135 30.74 27.55Footnote (9) 43.25 8.07Footnote (10) 13.64Footnote (11) 48.49 1.95 13.22
2.10E 14 480 31.85 27.55Footnote (9) 44.60 8.07Footnote (10) 13.64Footnote (11) 50.00 1.95 13.58

Isometric profile drawings oriented to demonstrate edge (joist) loading and face (plank) loading
Figure 2. Load direction with respect to strand orientation
  1. Edge (joist) loading
  2. Face (plank) loading


  • Edge/joist loading is parallel to WFS
  • Face/plank loading is perpendicular to WFS

Table 2. TimberStrand® LSL fastener detail: all grades
Fastener property Nail orientation Load direction Specific gravity of equivalent species for design purposes
Nail withdrawal Edge Withdrawal S-P-F, SG = 0.42
Nail withdrawal Face Withdrawal D Fir – L (N), SG = 0.501
Lateral nail capacity Edge Parallel to grain D Fir – L (N), SG = 0.50
Lateral nail capacity Edge Perpendicular to grain D Fir – L (N), SG = 0.50
Lateral nail capacity Face Parallel to grain D Fir – L (N), SG = 0.50
Lateral nail capacity Face Perpendicular to grain D Fir – L (N), SG = 0.50
Bolt bearing capacity Parallel to grain D Fir – L (N), SG = 0.50
Bolt bearing capacity Perpendicular to grain D Fir – L (N), SG = 0.50
  Bolt size Load direction Specified strength (N)
Lag screw capacity 12.7 mm Parallel to grain 2 820Footnote (1)
Lag screw capacity 12.7 mm Perpendicular to grain 2 820Footnote (1)


Table 3. Nail spacing requirements for TimberStrand® LSL
Closest on centre nail spacing parallel to WFS orientation (mm)Footnote (1) Footnote (2)
Common nail size Nominal member thickness (mm)
32 38 44.5-89 89
1 Row 2 Rows 1 Row 2 Rows 1 Row 2 Rows 3 Rows 3 Rows
63.5 mm × 3.33 mm 102 102 76 76 76 76 76 76
76 mm × 3.75 mm 102 102 76 76 76 76 76 76
89 mm × 4.11 mm 152Footnote (3) 152Footnote (3) 152Footnote (3) 152Footnote (3) 152Footnote (4) 152Footnote (4) 152Footnote (4) 152Footnote (4)


Table 4. TimberStrand® LSL 1.3E rim board factored resistance valuesFootnote (1)
Nominal thickness (mm) Limit states design factored vertical load resistanceFootnote (2) (kN/m) Depth range (mm)
32Footnote (3) 98.20 ≤ 406
32Footnote (3) 79.75 > 406, ≤ 508
38 95.65 ≤ 610


Table 5. TimberStrand® LSL stud and shear wall applicationsFootnote (1) Footnote (2)
TimberStrand® LSL grade NailingFootnote (3) Footnote (4) Species factor for framing material (Jsp)
GradeFootnote (5) < 1.5E Panel edge nailing of 150 mm 0.8
1.5E ≤ Grade < 1.6E Panel edge nailing of 75 mmFootnote (6) to 150 mm 0.8
1.6E ≤ Grade ≤ 1.7E Panel edge nailing of 75 mm to 150 mm 1.0
Manufacturing quality assurance program

The manufacturing quality assurance program (QAP) has been updated to include requirements specified in ASTM D 5456-13a, “Standard Specification Evaluation of Structural Composite Lumber Products,” and has been verified by independent, third-party monitoring and inspection conducted by PFS Corporation and Intertek Testing Services NA Ltd. as part of the product certification.

Design values obtained from testing to ASTM D 5456-13a  

The design values obtained from testing to ASTM D 5456-13a as specified in CSA O86-14 are summarized below.

Table 6. Additional test information for TimberStrand® LSL
Property Test information
Bending Specimens were tested in edgewise and flatwise bending to establish the characteristic value. Data from quality control (QC) tests were used to establish the applicable coefficient of variation, CVw, and the reliability normalization factor from CSA O86-14 was used to determine the specified strength.
Shear Specimens were tested in shear to establish the characteristic value. Data from QC tests were used to establish the applicable coefficient of variation, CVw, and the reliability normalization factor from CSA-O86-14 was used to determine the specified strength.
Compression parallel to grain Specimens were tested in compression parallel to grain to establish the characteristic value. Data from QC tests were used to establish the applicable coefficient of variation, CVw, and the reliability normalization factor from CSA-O86-14 was used to determine the specified strength.
Compression perpendicular to grain Specimens were tested in compression perpendicular to grain to establish the characteristic value. The two methods, namely, min. density and 0.04 in. deformation stress, were used with a voluntary adjustment of 0.71 by the proponent. The characteristic value was multiplied by 1.09 to establish the specified strength in accordance with CSA O86-14 and ASTM D 5456-14b.
Tension parallel to grain Specimens were tested in tension to establish the characteristic value. Data from QC tests were used to establish the applicable coefficient of variation, CVw, and the reliability normalization factor from CSA-O86-14 was used to determine the specified strength.
Nail withdrawal Nail withdrawal values were established following ASTM D 1761-12, "Standard Test Methods for Mechanical Fasteners in Wood," for an 8d common nail having a 31.75 mm penetration. Specimens were tested, and equivalent species capacity was determined in accordance with ASTM D 5456-13a, A2.4.
Nail bearing Dowel bearing strength was determined as per ASTM D 5764-97a, "Standard Test Method for Evaluating Dowel-Bearing Strength of Wood and Wood-Based Products," using 10d common nails with a nominal diameter of 3.76 mm and a lead hole diameter of 2.77 mm. Specimens were tested, and the mean bearing capacity was used to establish the equivalent species capacity as per ASTM D 5456-13a, A2.5.
Bolt bearing Bolt bearing capacity was determined in accordance with ASTM D 5764-97a using 12.5 mm and 19.0 mm bolts. Specimens were tested, and the mean bolt bearing capacity was used to establish the equivalent species capacity as per ASTM D 5456-13a A2.5.
Creep and recovery A total of 240 specimens were tested to a short-term and long-term creep assessment program. The creep performance of the product was found to be equal to or better than Aspen lumber. Long-term (90 day) creep testing was also conducted. It demonstrated equivalency to the duration of load behaviour of sawn lumber.
Fire resistance Two full-scale floor assemblies were tested, one containing sawn lumber joists and the other TimberStrand® LSL joists. Charring rate tests were also conducted for comparison. The testing and performance were considered adequate to demonstrate equivalency to the fire resistance of sawn lumber joists within a fire-rated floor assembly.
Adhesive See CSA O325-07, "Construction Sheathing" (OSB binder requirements). For adhesive and species mix qualification, additional creep testing was conducted in accordance with CCMC’s creep and recovery test. After conditioning of the specimens, the creep and recovery performance was considered favourable.
Zinc borate treatment As the product is treated with zinc borate in accordance with AWPA N2-03, "Composite Wood Products, Preservative Treatment by Nonpressure Processes," it was found to be effective in controlling decay from environmental conditions expected in sill plate applications.
Stud (general) Notching: Strength and stiffness reduction for a 22 mm × 75 mm notch in 1.3E TimberStrand® LSL was compared with "standard and better" Douglas fir sawn lumber (not NBC specified minimum stud lumber). The Douglas fir lumber showed 70% reduction, while the 1.3E LSL showed 43% reduction.
End nail connection: Lateral nail capacity of 10 stud/plate connections were tested with 4 mm to 82 mm (16d) nails, and a minimum 5 kN was attained, which exceeds the 3.77 kN criterion.
Nail slip, en, performance (optional): The sheathing-to-framing connection was tested for nail slip, and in combination with full-scale shear wall test results, 1.3E grade showed a similar load-slip relationship to "dry assemblies/dry use" SG = 0.50 material.
Studs in shear walls Full-scale shear wall tests of various combinations and permutations of LSL grades, sheathing thickness, nail size and spacing were undertaken to verify equivalency to lumber shear walls in Table 9.5.1.A in CSA O86-09. Testing was performed following the CUREE Method C in ASTM E 2126, "Standard Test Methods for Cyclic (Reversed) Load Test for Shear Resistance of Vertical Elements of the Lateral Force Resisting Systems for Buildings." Three parameters needed to be met based on the equivalent energy elastic-plastic (EEEP) curve. The three parameters included: (i) ductility (μ) ≥ 11; (ii) drift capacity (Du) ≥ 0.028H; and (iii) 2.3 ≤ overstrength (Ω) ≤ 5.0. These criteria were met for the LSL grades, panel edge spacing and species adjustment outlined in Table 5.
Conditions and limitations for stud and shear wall applications  

For use in Part 9 applications:

  1. For general stud applications, notwithstanding that Article, Wall Studs, of the NBC 2015 permits notching of stud grade lumber up to 1/3 the depth, TimberStrand® LSL studs must not be notched more than 25% of stud depth.
  2. Braced wall panels utilizing LSL studs are subject to the limitations in Article, Limitations, of the NBC 2015 as applicable.
  3. Fasteners for sheathing must conform to Tables, and of the NBC 2015.
  4. Appropriate LSL grade must be specified for stud size and spacing must conform to Table of the NBC 2015.
  5. LSL stud-braced walls must be detailed in accordance with Subsection 9.23.13., Bracing to Resist Lateral Loads Due to Wind and Earthquake, of the NBC 2015.

For use in Part 4 applications:

  1. Blocked shear walls with LSL studs can be used as lateral load resisting systems in wood construction in Canada with no height limitation. Unblocked shear walls are limited to a height of 4.88 m (16 ft.) as per Section 11.4.4 of CSA O86-14.
  2. When a vertical load is present on any wall, it should be included in the design of the wall studs, especially in the case of high walls to avoid potential stud buckling.
  3. Framing members shall be at least 38 mm thick in shearwalls and diaphragms. For diaphragms with multiple rows of fasteners, framing members shall be at least 64 mm thick and 64 mm wide at boundaries or adjoining panel edges as per Clause of CSA O86-14.
  4. Blocked shear walls must be used in high seismic zones (i.e., Part 4, where IEFaSa(0.2) ≥ 0.35, and Part 9, where Sa(0.2) ≥ 0.7 in the NBC 2015).
  5. Double-sided walls with LSL studs should be a minimum nominal 2 in. × 6 in. Nails must be attached in accordance with Clause and Table 11.5.4 of CSA O86-14.
  6. In cases where double studs are used in walls with LVL/LSL studs, the connection between plies must be designed with mechanical fasteners to resist the shear force at the stud interface and prevent separation of the studs. Relatively large forces are generated between the studs during the shear wall response, especially in the end studs and at studs on the perimeters of the panels.
  7. The nail diameter for sheathing-to-framing connections in any wall must not exceed 3.7 mm.
  8. The nail spacing in any case must be equal to or greater than the minimum nail spacing of 76 mm.
  9. The size of the nail heads should be equal to or larger than those of the nails used in the testing program.
  10. Maximum sheathing thickness of 15.8 mm (5/8 in.) can be used in combination with the same length of nails and nail spacing as used in the testing. Sheathing thickness beyond 15.8 mm (5/8 in.) is not permitted.
  11. See Table 5, Note 5.
  12. The stud spacing must not exceed 610 mm (2 ft.) o.c.




Administrative information


This evaluation is issued by the Canadian Construction Materials Centre (CCMC), a part of the Construction Research Centre at the National Research Council of Canada (NRC). The evaluation must be read in the context of the entire CCMC Registry of Product Assessments and the legislated applicable building code in effect.

The CCMC was established in 1988 on behalf of the applicable regulator (i.e., the provinces and territories) to ensure—through assessment—conformity of alternative and acceptable solutions to regional building codes as determined by the local authority having jurisdiction (AHJ) as part of the issuance of a building permit.

It is the responsibility of the local AHJs, design professionals, and specifiers to confirm that the evaluation is current and has not been withdrawn or superseded by a later issue. Please refer to the website or contact:

Canadian Construction Materials Centre
Construction Research Centre
National Research Council of Canada
1200 Montreal Road
Ottawa, Ontario, K1A 0R6
Telephone: 613-993-6189
Fax: 613-952-0268

The NRC has evaluated the material, product, system or service described herein only for those characteristics stated herein. The information and opinions in this evaluation are directed to those who have the appropriate degree of experience to use and apply its contents (i.e., AHJs, design professionals and specifiers). This evaluation is only valid when the product is installed in strict compliance with the stated conditions and limitations of evaluation and the applicable local building code. In circumstances where no applicable local building permit is issued and that no confirmation of compliance ‘for use in the intended field application’ is undertaken, this evaluation is null and void in all respects. This evaluation is provided without representation, warranty, or guarantee of any kind, expressed, or implied, and the NRC provides no endorsement for any evaluated material, product, system or service described herein. The NRC accepts no responsibility whatsoever arising in any way from any and all use and reliance on the information contained in this evaluation with respect to its compliance to the referenced code(s) and standard(s). The NRC is not undertaking to render professional or other services on behalf of any person or entity nor to perform any duty owed by any person or entity to another person or entity.


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© His Majesty the King in Right of Canada, as represented by the National Research Council of Canada, 2022

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior written permission of the CCMC.