02813 Telecom Duct Banks

SECTION 02813 UNDERGROUND TELECOMMUNICATION DUCTBANKS AND JOINTING CHAMBERS

PART 1 – GENERAL 1.1

DESCRIPTION OF WORK

A.

The work of this section includes the provision of equipment, materials, supervision and labor required to construct and install underground telecommunications ductbanks and jointing chambers (manholes, handholes and associated accessories).

B.

Related Work: 1.

Section 01570:

Maintenance and Control of Traffic

2.

Section 02200:

Earthwork

4.

Section 03300:

Cast-in-Place Concrete

5.

Section 03400:

Precast Concrete

6.

Section 07100:

Dampproofing and Waterproofing

1.2

QUALITY ASSURANCE

A.

The following list identifies organizations that publish codes, standards, and manuals referenced herein: 1.

ASTM:

American Society for Testing and Materials 1916 Race Street Philadelphia, P.A. 19103 U.S.A.

2.

BS:

British Standards Institute 2 Park Street London WYY 4 AA United Kingdom

3.

DIN:

Deutsche Industrie Norm (German Industrial Standards) Deutscher Normenausschuss D-1000 Berlin 30 West Germany

P.O. Number : 7200018725

1.3

4.

ISO:

International Organization for Standardization 1, Rue de Vasembe CH-1211 Geneve 20 Switzerland

5.

MAT:

Material Specification Ministry of Post, Telegraph and Telephone Riyadh Kingdom of Saudi Arabia

6.

SAS:

Saudi Arabian Standards Organization P.O. Box 3437 Riyadh Kingdom of Saudi Arabia

SUBMITTALS Shop Drawings: Submit shop drawings for MARAFIQ's review. Completeness of shop drawings shall be sufficient to indicate compliance with Contract Documents.

1.4

PRODUCT DELIVERY, STORAGE AND HANDLING

A.

Deliveries: Deliver materials in manufacturer's original packaging with all tags and labels intact and legible.

B.

The following information shall be visible on shipping crates and protective wrapping:

C.

1.

Name of manufacturer of polyvinyl chloride (PVC) or polyethylene (PE) materials and accessories. accessories.

2.

Code number of manufacturer.

3.

Address of manufacturer.

4.

Name and telephone number of local representative.

Storage and Handling: Store and handle materials to avoid damage and interference with work of other trades. Protect PVC and PE materials from exposure to sunlight. Store PVC ducts and prefabricated bends to prevent sagging or other mechanical damage.

P.O. Number : 7200018725

PART 2 – PRODUCTS 2.1

POLYVINYL CHLORIDE (PVC) DUCTS AND FITTINGS

A.

Ducts and fittings shall be manufactured of rigid PVC without the use of plasticizers. Lubricants, stabilizers, antioxidants, and pigments may be added to material. No constituent material may be used in the PVC which will adversely effect the long term mechanical strength. All constituents shall be uniformly and and fully dispersed.

B.

Color: Color shall be black or gray to indicate telecom duct.

C.

Requirements of Ducts and Couplings: Ducts and couplings shall be homogeneous material. All surfaces shall be clean, smooth, and without any visible cracks, grooves, blisters, wrinkles, dents, heat marks, or foreign particles. Ends must be square and free from sharp edges.

D.

Mechanical and Thermal Properties shall meet requirements as follows:

1.

2.

Test Method

Tensile Strength:

ASTM D638 DIN 53455

Ultimate Elongation:

ASTM D638 DIN 53455 BS 2782/301F

Requirements

170 kg per cm2 min. BS 2782/301F

350% minimum.

3.

Hardness:

ASTM D2240 DIN 5305

60 D.

4.

Impact Brittleness: Britt leness:

ASTM D746

Below -4°C. -4°C.

5.

Dielectric Strength:

ASTM D149 DIN 53481 BS 2782/201

120 kV per cm.

6.

7. E.

Test

Volume Resistivity:

Thermal Aging:

ASTM D257 DIN 53482 BS 2782/202A 168 hours at

1012 ohm cm. 150°C + 2°C.

Dimensions: 1.

Ducts shall have nominal outside diameters of 50 mm or 110 mm.

P.O. Number : 7200018725

2.

Ducts shall be PVC Series 3 and have nominal wall thickness of 1.8 mm for 50 mm and 3.2 mm for 110 mm. Wall thicknesses shall have a tolerance of -0 mm and +0.2 mm.

3.

Tolerance for out-of-roughness shall be less than +1.0 mm.

4.

Straight ducts shall be provided in lengths of 6 meters including a socket at one end.

5.

Ducts shall be marked clearly and indelibly as follows: Telecommunications - MARAFIQ Duct Nominal Outside Diameter: (mm) Manufacturer's Code or Trade Mark.

6.

Fittings for joining ducts shall be a minimum length of 160 mm and made of the same material as ducts.

7.

Dimensions for PVC ducts and fittings shall meet the following standards: (a) SAS 14 : PVC Pipe (b) DIN 8062 : Rigid PVC Pipe Dimensions

F.

Bends: 1.

Bends shall be fabricated of the same material as PVC ducts.

2.

Standard bends shall be available availabl e in 45° and 90° angles and provided with a socket at one end. Also, they shall be fabricated in the following radii: Nominal Outside Diameters (mm) 50 110

Bend Radii (m) 1.0, 2.5, 5.0, & 10.0 5.0 & 10.0

2.2

HOT DIPPED GALVANIZED STEEL PIPE

A.

Rigid hot dipped galvanized steel pipe shall be used where ductbanks cross highways, deep wadis or areas where ground conditions are unstable. Rigid pipe/PVC adapter fittings shall be used where duct material changes occur.

P.O. Number : 7200018725

B.

C.

Rigid steel pipes shall be welded or seamless and free from dents and internal roughness. Ends shall be reamed and free from metal burrs to prevent abrasion and damage to cable sheath. Pipe dimensions shall be as follows:

Size

Outside Diameter

Wall Thickness

50 mm 100 mm

60.3 mm 114.3 mm

3.91 mm 6.02 mm

The following standards shall apply: 1.

ISO R 630

:

Steel Quality

2.

ISO R 228

:

Threads

3.

ISO R 1459 :

Corrosion Protection

4.

ISO R 1460 :

Hot Dipped Galvanizing – Ferrous Materials

5.

ISO R 1461 :

Hot Dipped Galvanizing – Fabricated Ferrous Materials

6.

ASTM A120 :

Pipe

2.3

SPACERS

A.

Spacers shall be used to maintain a 30 mm uniform separation between assembled ducts in both the vertical and horizontal directions.

B.

When ductbanks consist of ducts with both 50 mm and 110 mm sizes, appropriate spacers shall be used.

C.

Splaying of ductbank configurations is permissible to clear obstructions or avoid right-of-way restrictions. Realignment to the original configuration must be made once the obstruction of right-of-way restriction has been cleared.

D.

Spacers shall be made of polyethylene (PE) or polyvinyl chloride (PVC) material.

2.4

WARNING TAPE

A.

Warning tape for ductbanks shall be yellow PVC tape.

B.

The warning tape shall be 300 mm x 0.125 mm.

C.

The following shall be printed on the tape in both Arabic and English and in durable black letters of 50 mm height:

P.O. Number : 7200018725

"Warning - TELECOMMUNICATION DUCT." 2.5

STEEL TROUGHS

A.

Steel troughs shall be used where ducts rise and terminate at building walls. Troughs are "U" shaped and are also sometimes referred to as "U"-Guard.

B.

Troughs shall be manufactured from hot dipped galvanized hot-rolled steel. Galvanizing shall conform to requirements of 450 gr/m2 and per standards ISO RI459 through 1461. Troughs shall be provided in lengths of 1500 mm and 3000 mm and in the following sizes. 1.

30 mm x 30 mm x 1 mm

2.

55 mm x 55 mm x 1 mm

3.

105 mm x 105 mm x 1 mm

2.6

DUCT SEALS

A.

Duct seals shall be installed to seal used and unused ducts terminated in jointing chambers, buildings and walls. After sealing, ducts must be watertight.

B.

Duct seals shall be made of plastic, neoprene rubber or heat shrinkable material.

C.

Mechanical and thermal properties shall meet the following standards: Test 1.

2.

Test Method Tensile Strength:

Ultimate Elongation:

3.

Impact Brittleness: Britt leness:

4.

Thermal Aging:

Requirement

ASTM D638 DIN 53455

100 kg per cm2 min. BS 2782/301F

ASTM D638 DIN 53455 BS 2782/301F

200% minimum.

ASTM D746

Below -4°C. -4°C.

168 hours at 150°C 150°C +_2°C. +_2°C.

P.O. Number : 7200018725

2.7

JOINTING CHAMBERS

A.

Jointing chambers shall consist of two types: manholes and handholes. Jointing chambers shall be constructed of steel reinforced concrete and shall be watertight.

B.

Ducts shall be designed to enter jointing chambers only in the longitudinal axis.

C.

PVC ducts shall enter jointing chambers via cable duct connection slabs fabricated from polyurethane foam for manholes and precast concrete or other suitable material for handholes.

2.8

MANHOLES

A.

The size and type of manholes shall be dependent on the number of ducts terminated. Refer to MARAFIQ Standard Drawings RC-T-1 and RC-T-4.

B.

Manholes shall be watertight. To ensure water tightness, all prefabricated section joints and duct entrance slab joints shall be properly sealed.

C.

The exterior of all manholes shall be damp proofed or waterproofed in accordance with the requirements of Section 07100.

D.

Manhole Entrance: 1.

Manholes shall be constructed with a round entrance facility through the roof. This shall be referred to as the manhole neck and consist of a round collar, frame, cover and entrance shaft. The frame and cover shall be securely mounted on the collar with the top of the cover set to final grade. The total length of the entrance shaft (measured through neck from top of frame and cover to bottom surface of roof) shall not exceed 1500 mm except under special conditions (see paragraph 2.8.D.2). The entrance shaft shall be a minimum diameter of 690 mm and the collar shall be a minimum height of 150 mm above the top surface of the manhole. The height of the collar may be sized during construction construction to mount the frame and cover cover to final grade; or, the collar may be constructed to a minimum height and subsequently extended by the use of extension and adjustment rings to set the frame and cover to final grade. In either case, the shaft shall contain steps as required at 300 mm intervals to facilitate a safe entrance into the manhole.

2.

Should special conditions warrant construction of entrance shafts greater than 1500 mm in length, MARAFIQ shall be consulted prior to commencing shop drawings.

P.O. Number : 7200018725

E.

Manholes shall be provided with a sump approximately 300 mm x 300 mm located directly below the manhole opening. The floor of the manhole shall slope slightly towards the sump for positive drainage.

F.

Manholes shall be fabricated of steel reinforced concrete complying with requirements of Section 03300 or 03400. The concrete mixture shall be in accordance with MAT 041 (Raw Materials for Concrete).

G.

Manholes shall withstand an evenly distributed load of backfill and road surfacing of 12 kPa and a traffic load of 200 kN + 50% overload for impact from moving vehicles. Covers shall withstand standard truck loading of AASHO HS20-44 + 10%.

H.

Manhole racking bays shall be located on the side walls and at 90° to duct entry walls. Splicing bays shall not be designed on oblique wall bays.

I.

A ladder and related support (step or bottom step) shall be considered as part of all manholes.

J.

Manhole Accessories: Each manhole shall be equipped with the following: 1.

Neck: A neck is required to extend the manhole opening to the final grade of road, landscaped, or paved surfaces. The neck shall consist of a collar, frame, cover cover and entrance shaft. The length of the neck may be adjusted by the use of frame extension rings in accordance with MAT 626 (Manhole Frame Extension) or by the installation of precast concrete rings attached to the collar.

2.

Frame and Cover:

3.

(a)

The frame and cover shall be made of cast iron and dimensioned to withstand loads stated in paragraph 2.8G. The frame and cover shall comply with BS 1452 and MAT 628 and be designed to ensure no rocking.

(b)

The cover shall have a diameter of approximately 730 mm and an inscription on top with the word “Telecommunications" in both Arabic and English. Two pricing slots and four lifting holes shall be provided to facilitate easy removal.

Cable Duct Connection Slabs: Connection of PVC ducts to manhole end walls shall be made by the use of cable duct connection slabs. Connection slabs are required to ensure that ducts are properly terminated and watertight. Material for slabs shall be polyurethane foam or other suitable material. Sizes

P.O. Number : 7200018725

shall be sufficient to accommodate the number of ducts terminating in the manhole. 4.

Cable Hanger Rails: Hanger rails shall be installed in manholes for attachment of hangers to support telephone and CATV cables. Rails shall be be able to sustain both vertical and horizontal loading of 5 kN and provided in two lengths. Rails shall be made of stainless steel ASTM type 304. 304.

5.

Cable Hangers: Cable hangers shall consist of stainless steel ASTM type 304 bearing arms and plastic brackets which shall pivot slightly on the bearing arm to support support the cables. cables. Hangers shall be provided on each side of the manhole for each layer of duct. Hangers shall be provided in length of 420 mm.

6.

Pulling-In Eyelets:

7.

(a)

Pulling-in eyelets shall be installed in manhole floors. The locations shall be in line with the center line of each ductbank at the opposite end of the manhole. Installed eyelets shall withstand a pulling force of 30 KN. Eyelets shall be secured to reinforcing steel of manholes prior to pouring of concrete or fabrication of precast end sections.

(b)

Pulling-in eyelets shall be made of stainless steel ASTM type 304.

Ladder and Ladder Support: (a)

The ladder shall consist of two straight and parallel rails with rungs at 300 mm intervals as required. The top of each rail shall be equipped with a hook securely fixed with bolts, lock washers and nuts. The hooks shall be fixed to the inside surface of the side rails. Each hook shall be attached by at least two bolts and nuts. The hooks shall be easily adjustable and have an approximate range range of 100 mm to 200 mm.

(b)

The ladder shall be made of steel having minimum tensile strength of 300 MPa. The finish shall be hot dipped galvanized per ISO 1459 to R1461 with a minimum coverage of 500 g/m2. All bolts, nuts, washers and rivets shall be made of steel and similarly galvanized. Rungs shall be non-slip corrugated steel bars 15 mm in diameter. All parts, including galvanizing, shall have a smooth finish.

(c)

The ladder shall be of appropriate length for the type of manhole in which it is installed. The ladder shall be of

P.O. Number : 7200018725

adequate length so it is properly seated on the floor with sufficient incline for easy climbing. (d)

The ladder support shall consist of the bottom step mounted in the entrance shaft.

8.

Sump Cover Grille: A sufficiently strong metal sump cover grille shall be provided. When installed, it shall not rock, shall be easily removable and fit flush with the manhole floor. The grille shall be hot dipped galvanized per standards ISO R1459 to R1461 with a minimum coverage of 650 g/m2.

9.

Number Plate: Each manhole shall have a brass number plate fastened to the shaft. Plates shall be made of brass or durable plastic material and securely fastened with lag screws or anchors, mounted at a uniform height and location adjacent to the ladder. Placement shall be such that the plate may be read without entering the manhole.

10.

Cable Duct Direction Plates: Each manhole shall be equipped with cable duct direction plates indicating the route of each duct to adjoining manholes and/or handholes. Plates shall be made of durable plastic material and securely fastened with lag screws or anchors to the manhole wall above or adjacent to each ductbank.

2.9

HANDHOLES

A.

Handholes shall be constructed of cast-in-place or precast reinforced concrete. The concrete shall comply with requirements of Sections 03300 or 03400 and MAT 041. For size and type of handholes refer to MARAFIQ Standard Drawing RC-T-5.

B.

Handholes shall be watertight. To ensure watertightness, properly sealed duct entrance slabs shall be installed at opposite ends of the handhole along the longitudinal axis.

C.

The exterior of all handholes shall be damproofed and waterproofed in accordance with Section 07100.

D.

Handholes shall withstand an evenly distributed load of backfill and road surfacing of 12 kPa and a traffic load of 200 kN + 50% overload for impact from moving vehicles. Covers shall withstand standard truck loading of AASHO HS20-44 + 10%.

P.O. Number : 7200018725

E.

Handhole Accessories: Each handhole shall be equipped with the following: 1.

Frame and Covers: A rectangular opening shall be formed into the top of the handhole to accommodate a frame required to support the covers. Covers shall be made of cast iron and sized to withstand the load stated in paragraph 2.9D. Covers shall fit into the frame without rocking. Each cover shall be inscribed in Arabic and English with the word "Telecommunications." This inscription shall be cast into the face of each cover.

2.

Cable Duct Connection Slabs: Ducts shall terminate in cable duct connection slabs to ensure watertight- ness of the handhole. Slabs shall be constructed of concrete or other suitable material.

3.

Hanger Rails: Hanger rails shall be installed in each handhole for attachment of hangers to support telephone and CATV cables. Rails shall be able to sustain both vertical and horizontal loading of 5 kN. Rails shall be made of stainless steel ASTM type 304.

4.

Cable Hangers: Cable hangers shall consist of stainless steel ASTM type 304 bearing arms and plastic brackets which shall pivot slightly on on the bearing arm to support cables. Two (2) hangers shall be provided on each side of the handhole. Hangers shall be provided in a length of 250 mm.

5.

Number Plate: Each handhole shall have a number plate fastened to the end wall. Plates shall be made of brass or durable plastic material and securely fastened with lag screws or anchors, mounted at a uniform height and location.

6.

Cable Duct Direction Plates: Handholes shall be equipped with cable duct direction plates indicating the route of each duct to adjoining manholes and/or handholes. The plates shall be of durable plastic material and securely fastened with lag screws or anchors to the handhole wall above or adjacent to each ductbank.

PART 3 – EXECUTION 3.1

CONSTRUCTION OF DUCTBANKS AND JOINTING CHAMBERS

A.

Trenching and removal of earth shall be in accordance with Section 02200. In high water table areas, well points and drainage shall be incorporated into the work. Size of trenches shall be dependent on the number of ducts per bank as well as final grade elevations. Recommended trench sizes are indicated on Table 1.

P.O. Number : 7200018725

B.

Dimensions of pits for jointing chambers shall depend on the design and size of the jointing chamber including the height of the neck. Refer to Tables 2 and 3 for recommended excavation sizes for manholes and handholes.

C.

Preparation of Trench: Bottom of trenches shall be covered with layer of sand 0.1 m thick.

D.

Construction Methods of Jointing Chambers: 1.

Prefabricated Chambers: Prefabrication shall be the preferred method of constructing jointing chambers. Prefabricated chambers shall comply with Section 03400.

2.

Cast-In-Place Chambers: Where prefabrication methods are not economically viable or where reconstruction of chambers is required, chambers may be cast-in- place. Cast-in-place chambers shall comply with Section 03300.

E.

Change in Ductbank Configuration: Where it may be required to change ductbank configurations due to clearance limitations, spacers shall be located to give adequate support in the transition area. Ducts shall be in the same configuration on each side of the transition. The distance between ducts during the transition shall be a minimum of 30 mm.

F.

Cold Bends: Cold bends may be fabricated on site. Ducts shall be assembled outside of the trench and lowered into place. Joints shall be located outside of the curve whenever possible. Supports shall be positioned to maintain at least 30 mm between ducts.

G.

Prefabricated Bends: Prefabricated bends shall be laid in the same manner as cold bends including the placement of spacers. Only minor cold bend corrections of prefabricated bends shall be permitted. D&P / AUGUST 08 02813 - 13 Contract No. STG 5 & 6

H.

Duct Connections and Terminations: Duct connections and terminations shall be watertight. Watertightness shall be in accordance with values shown on Table 4. The Contractor shall propose acceptable joining and termination techniques.

I.

Concrete Encasement and Steel Reinforcement: All ductbanks or single ducts shall be concrete encased prior to backfilling. At locations where ductbanks or single ducts cross roads or highways, they shall be concrete encased with steel reinforcement.

J.

Installation of Spacers: Spacers shall be installed at maximum intervals of 3.0 meters.

P.O. Number : 7200018725

K.

3.2

Backfilling: 1.

Backfilling shall not commence until duct work has been inspected and approved by the MARAFIQ.

2.

Backfilling, including compaction tests, removal of spoil, and restoration of surfaces to grade, shall comply with Section 02200.

3.

Landscaping shall be provided and/or restored to original condition.

MANHOLE SPACING

A.

Manhole spacing shall not exceed 270 m for a straight ductbank run. The manhole spacing for ductbank runs with bends will be reduced and shall be individually calculated by the Contractor. MARAFIQ will provide reference documentation for the calculation of manhole spacing.

3.3

PROTECTION FROM OTHER UTILITIES

A.

When crossing other utility lines and facilities, a minimum of 0.3 m separation shall normally be maintained. If 0.3 m cannot be met, ducts shall be underpinned by reinforced concrete or by other approved methods.

B.

Horizontal separation from other utility lines and facilities shall not be less than 1.0 m.

3.4

PRESSURE TESTING Individual ducts shall be pressure tested upon completion of installation to ensure that all joints are properly sealed and ducts are not defective. The test pressure shall be 1.5 bar for 2 minutes after a "steady state" is achieved and shall show no evidence of leaking. For ducts deeper than 1.0 meter, see Table 4 for additional test pressure requirements. D&P /  AUGUST 08 02813 - 14 Contract No. STG 5 & 6

3.5

COMPLETION TESTING Ducts shall be swabbed out to remove all sand, dirt, stones and mud. Ducts shall be mandril tested (minimum allowable diameter shall be 95 mm for 110 mm and 42 mm for 50 mm ducts). Dimensions of mandrils shall be 95 mm x 300 mm for 110 mm ducts and 42 mm x 200 mm for 50 mm ducts. After mandrilling, a 6 mm nylon pull rope shall be installed in each duct and seals installed in all duct ends.

P.O. Number : 7200018725

TABLE 1 TRENCHES FOR PVC DUCTS Duct Assembly

Size of Trench

Configuration (layer x ducts per layer)

W (m)

H (m)

Without Timbering (m)

With Timbering (m)

D (m)

1x1

0.11

0.11

0.60

0.90

0.95

1x2 2x2 3x2 4x2 5x2 6x2 7x2 8x2 1x3 2x3 3x3 4x3 5x3 6x3 7x3 8x3 1x4 2x4 3x4 4x4 5x4 6x4 7x4 8x4 1x5 2x5 3x5 4x5 5x5 6x5 7x5 8x5

0.25

0.39

0.53

0.67

0.11 0.25 0.39 0.53 0.67 0.81 0.95 1.09 0.11 0.25 0.39 0.53 0.67 0.81 0.95 1.09 0.11 0.25 0.39 0.53 0.67 0.81 0.95 1.09 0.11 0.25 0.39 0.53 0.67 0.81 0.95 1.09

0.65

0.80

0.95

1.10

0.95

1.10

1.25

1.40

0.95 1.05 1.20 1.35 1.50 1.65 1.75 1.90 0.95 1.05 1.20 1.35 1.50 1.65 1.75 1.90 0.95 1.05 1.20 1.35 1.50 1.65 1.75 1.90 0.95 1.05 1.20 1.35 1.50 1.65 1.75 1.90

P.O. Number : 7200018725

TABLE 1 TRENCHES FOR PVC DUCTS Duct Assembly Configuration (layer x ducts per layer) 1x6 2x6 3x6 4x6 5x6 6x6 7x6 8x6 1x7 2x7 3x7 4x7 5x7 6x7 7x7 8x7 1x8 2x8 3x8 4x8 5x8 6x8 7x8 8x8

W (m)

0.81

0.95

1.09

Size of Trench H (m)

0.11 0.25 0.39 0.53 0.67 0.81 0.95 1.09 0.11 0.25 0.39 0.53 0.67 0.81 0.95 1.09 0.11 0.25 0.39 0.53 0.67 0.81 0.95 1.09

Without Timbering (m)

1.25

1.35

1.50

With Timbering (m)

1.55

1.65

1.80

D (m)

0.95 1.05 1.20 1.35 1.50 1.65 1.75 1.90 0.95 1.05 1.20 1.35 1.50 1.65 1.75 1.90 0.95 1.05 1.20 1.35 1.50 1.65 1.75 1.90

P.O. Number : 7200018725

TABLE 2 EXCAVATION FOR MANHOLES Size of Manhole Inside Demension

Size of Excavation Maximum Size

MH Type

Length

Width

Depth

Length

Width

Depth

I II III IV Va

2.50 3.90 5.00 6.10 7.20

1.50 1.50 1.80 2.00 2.20

2.10 2.10 2.10 2.10 2.10

4.30 5.70 6.80 7.90 9.00

3.60 3.60 3.90 4.10 4.30

3.25 3.25 3.25 3.25 3.25

TABLE 3 EXCAVATION FOR HANDHOLES

Size of Manhole Inside Demension

Size of Excavation Maximum Size

MH Type

Length

Width

Depth

Length

Width

Depth

I II

1.40 1.40

0.80 0.80

0.60 1.08

2.70 2.70

2.20 2.20

1.00 1.50

TABLE 4 VALUES OF WATER TIGHTNESS Depth of Lowest Layer Underground Level

Test Pressure (Excess pressure in bar)

1.0 m 2.0 m 3.0 m 4.0 m 5.0 m 6.0 m 7.0 m

1.5 2.0 2.1 2.3 2.5 2.7 3.0

P.O. Number : 7200018725