NOTES TO THE SPECIFICATION FOR RAISED PAVEMENT MARKERS. These notes are for guidance and are not to be included in the contract documents.

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1 NOTES TO THE SPECIFICATION FOR RAISED PAVEMENT MARKERS These notes are for guidance and are not to be included in the contract documents. 1. SCOPE The scope has been introduced to define raised pavement marker types in accordance with Australian Standard (AS) : This includes expanding the specification for non-reflective markers to include non-ceramic markers. The colour of non-reflective markers has been limited to white to be consistent with the Transit New Zealand (Transit)/Land Transport Safety Authority (LTSA) guidelines such as the Manual of Traffic Signs and Markings and Road and Traffic Standards (AS allows white and. 2. GENERAL This section has been introduced to clarify the requirements and testing regimes for both type approval and subsequent quality control testing. The sample selection process has been changed and the sample number has been increased from the M/12 (1986) specification requirement of two samples per laboratory test to the AS requirement of five per test (Figure 1). This is in line with concerns expressed in a report on the revision of Transit Specifications P/14 and M/12 (Dravitzki, 1994), regarding both the low sample number and bias in favour of the manufacturer in the selection process. 3. REQUIREMENTS OF NON-RETROREFLECTIVE MARKERS 3.1 Field Trial (Non-ceramic Markers) This requirement is new, and is additional to the requirements of AS Previously M/12 only allowed ceramic non-retroreflective markers. Although plastic markers have previously been available on an experimental basis, they have tended to discolour and lose their reflectivity to an unacceptable level. However, the current AS does not restrict the composition of the markers. This is in line with the philosophy of a performance based specification and is therefore consistent with Transit s policy of moving towards performance based specifications. Further, it appears that plastic markers have recently been used successfully in Australia. Therefore, it was decided to widen the range of materials that could be used in the construction of markers. SP/NM12: NOTES FOR RAISED PAVEMENT PARKERS Page 1 of 13

2 Laboratory tests do not accurately predict the performance of non-ceramic markers, so the field trial has been included to provide the necessary indication of performance with respect to time and wear. Evidence that markers can meet these requirements, such as compliance with equivalent overseas field testing regimes that have similar climatic and road surface conditions to New Zealand, may be considered to help establish compliance, in lieu of the field trial. For ceramic markers the field trial is normally considered to be unnecessary and the laboratory tests alone are regarded as sufficiently rigorous indicators of their field performance. These markers could however be subjected to the field trial where doubt exists. 3.2 Laboratory Tests Appearance The general appearance requirements of the Australian Standard specification (AS : 1992) is included. The composition requirements which relate to the ceramic markers have been removed. No other material requirements have been set for other marker types. The proof of the suitability of composition should be compliant with the requirements of this specification. This philosophy is in line with the move by Transit toward performance based specifications. The shape and finish as detailed in M/12 (1986) has been retained, as it was felt that these markers should have a specific shape, which is not specifically stated in the AS specification Colour The AS method has been incorporated here for routine assessment. As given in the standard, this method is subjective. To remove the subjectivity, the acceptable colour of the comparison sample is defined by reference to CIE coordinates as per AS and M/12 (1986) Reflectivity The M/12 method cites an ASTM method (E97) for determining the reflectance factor which has been superseded by ASTM E It appears that the replacement specification produces the same result. Ultimately it would be desirable to adopt the AS method/requirement of a minimum luminance factor. However, until the relationship between the two systems, in particular the minimum value, has been established the approach of M/12 (1986) is being retained. SP/NM12: NOTES FOR RAISED PAVEMENT PARKERS Page 2 of 13

3 3.2.4 Water absorption This requirement has been replaced by that of AS , so both types (A and B) of raised pavement markers are now tested in the same way. The M/12 (1986) method was based on an ASTM (American) test for ceramic and white wear, which was modified for ceramic markers. This test required the marker to be subject to temperatures of 150 C, with assessment being by weight change. In contrast the requirement for type A markers was based on testing at 50 C, with assessment (more appropriately) being by measuring the before and after test changes in retroreflectivity. Incorporation of the AS : 1992 requirement also means that the reflectivity of the markers subsequent to testing will be by instrumental measurement, rather than by eye as in M/12 (1986) Heat and UV tests The AS requirements constitute new additions to M/12 (1986) in terms of type B markers. In M/12 (1986) these tests were required for retroreflective markers only. However, in AS they are required for both types of marker. Inclusion of these requirements is particularly relevant as the new M/12 scope is not restricted to proven ceramic, non-retroreflective markers. For example, non-retroreflective markers may be of similar material to the retroreflective (type A) markers, therefore their performance under this condition needs to be established. The requirement for the satisfactory test performance is based on comparison of the test marker with an acceptable control marker Compressive strength The AS : 1992 compressive strength/deformation requirements have been incorporated here. This is in line with report on the revision of M/12 and P/14 (Dravitzki, 1994) which expressed concern that there should be different requirements for retroreflective and non-retroreflective markers. AS requires the same values for both marker types Glaze thickness and hardness (ceramic only) The glaze thickness and hardness requirements of M/12 (1986) have been retained for ceramic markers. The glaze thickness requirement is that of AS and is referenced accordingly. SP/NM12: NOTES FOR RAISED PAVEMENT PARKERS Page 3 of 13

4 3.3 Tests Discontinued From M/12 (1986) Bond strength and impact tests Both the impact and adhesive bond strength tests have been removed. This is in line with comments from the report by Vince Dravitzki (1994), questioning the relevance of this requirement with respect to field performance. With respect to the bond strength test, M/12 (1986) and AS adhesive bond tests use epoxy, whereas thermoplastic and bituminous binders tend to be used in New Zealand as an adhesive for marker installation. The requirement for the marker to bond to the adhesive and road surface is specified in P/ REQUIREMENTS OF RETROREFLECTIVE MARKERS 4.1 Required Number of Specimens As discussed earlier, the sample number is to be increased from two to five per test (refer Figure 1 of M/12) consistent with the AS Field Trial The retroreflectivity values remain as the M/12 (1986) requirements, but the field trial is to be increased from 8 weeks to 12 months. This effectively increases the reflectivity performance required. Therefore, a marker which has a rapid CIL decay rate, and currently just passes the minimum CIL criteria at 8 weeks, but falls below this level shortly beyond this time, say at 10 weeks, will no longer meet the requirements of M/12 (1986). This revision does bring the M/12 requirement up to that of the current AS : Evidence that markers have met this requirement may be used to help establish compliance with further research required to improve and confirm the necessary level of visibility required by the motorist. 4.3 Appearance The required marker body (case) colour is now specified in P/ Retroreflectivity As mentioned in Clause 4.1 of the specification, compliance with the field trial is the primary retroreflectivity requirement for type A markers. However, it is useful for quality assurance purposes to gauge whether an as-new marker has a sufficiently high initial CIL value to ensure compliance with the field trial. SP/NM12: NOTES FOR RAISED PAVEMENT PARKERS Page 4 of 13

5 Australian research has found that the CIL value of type A markers of varying construction decay at different rates when exposed to traffic on the road surface. AS uses the rationale that, by determining the rate of decay for a given marker type from the field trial, it is then possible to establish what the minimum as-new CIL value should be in order to attain the minimum field trial values. This then can be useful in assessing whether subsequent markers of that brand and generic type have sufficiently high initial CIL values for acceptance in terms of quality assurance purposes. Decay rates for two generic marker types, A1 and A2, have been established and incorporated in AS : 1992, along with a criterium developed which can be applied to further types (type Awxyz). This process is detailed in AS Clauses 2.3 and , and determines the Performance Ratio (PR) of a given marker type. The PR is the CIL ratio of the new marker to the trafficked marker, and is specific for generic marker type and CIL geometry. In practice it has been found that markers of the same generic type can have different decay rates. Therefore, although this classification may be useful as guidance, this specification requires new retroreflective marker brands to be field trialed in order to establish their actual durability in terms of retroreflective performance. Alternately, evidence of compliance with the field test, for example AS may be accepted in lieu of the trial. The procedure detailed in AS , Clause may be useful in formulating the minimum as-new value required, once the decay rate has been established from the field trial. This formula together with the decay rates and classification is included here for background information: Type A1 markers are those with retroreflective elements behind one or more smooth plastic face(s) presented directly to oncoming traffic such that vehicle tyres come into direct contact with the face(s). Type A2 markers are those having retroreflective elements which comprise of a series of glass lenses or lens like devices, the front faces of which are presented directly to oncoming traffic such that vehicle tyres come into direct contact with the faces. Type Awxyz markers are those of different construction to types A1 and A2 which have been shown by the procedures of this specification to have different photometric performance characteristics from either of these types. Such markers are to be identified with wxyz signifying a three or four character alphanumeric code assigned by the manufacturer or supplier. SP/NM12: NOTES FOR RAISED PAVEMENT PARKERS Page 5 of 13

6 Table 2: Minimum Retroreflectivity (CIL) Values for Clean, New Markers (source AS : 1992, Tables 3.1 and 3.2) Entrance Angle β (deg) Observation Angle α (deg) Minimum CIL Values (mcd/lux) White Yellow Red Type A1 Markers Type A2 Markers Type Awxyz Markers *PR = Performance Ratio x PR*(1) 2.2 x PR (2) 2.0 x PR (3) 3.0 x PR (1) 1.3 x PR (2) 1.2 x PR (3) 1.5 x PR (1) 0.7 x PR (2) 0.6 x PR (3) 4.5 Compressive strength As discussed under non-retroreflective raised pavement markers, M/12 now incorporates the compressive strength/deformation requirements of AS : The M/12 (1986) requirements were based on an earlier edition of AS Impact and Adhesive Bond Strength As discussed under the non-retroreflective pavement markers section, these tests are to be deleted as they are considered irrelevant. 5. MARKING AND PACKAGING This requirement is the same in both M/12 (1986) and AS requirement is to be retained, but with reference added to AS : This A further requirement is that each marker is to be identified with generic brand and type of marker permanently imprinted on every marker. 6. REFERENCES AND SUPPORTING DOCUMENTS SP/NM12: NOTES FOR RAISED PAVEMENT PARKERS Page 6 of 13

7 American Society for Testing Materials (1990): Test Method for Colour and Colour Difference Measurement by Tristimulus (Filter) Colorimetry, ASTM E British Standards I (1990): Grey Scale for Assessing Change in Colour, ISO 105-A021987/ BS 1006-A02:1990. SDC Standard Methods, 5th edition, A02. BSI (British Standards Institute), London. Dravitzki, V.K. (1994): Revision of TNZ P/14 and M/12, Central Laboratories Report , Lower Hutt. Standards Australia (1993): Retroreflective Materials and Devices for Road Traffic Control Purposes: Part 1, Retroreflective Materials, AS : Standards Australia (1992): Retroreflective Materials and Devices for Road Traffic Control Purposes: Part 3, Raised Pavement Markers (Retroreflective and Non-retroreflective, AS : SP/NM12: NOTES FOR RAISED PAVEMENT PARKERS Page 7 of 13

8 APPENDIX A NOTES ON RAISED PAVEMENT MARKERS 1. TYPE Section 3.1 of M/12 covers type approval of raised pavement markers. Provisional approval will be considered on the production of independent evidence demonstrating compliance with Australian Standard 1906, Part "Retroflective Materials and Devices for Road Traffic Control Purposes". Provisional approval will be for a period of up to 3 months provided satisfactory steps have been taken to have the marker tested by an approved laboratory. 2. APPROVED MARKERS Tables 1 and 2 list the markers that have current approval in terms of M/12. Contract supervisors should check that the markers are the same as those submitted for testing when type approval was given. This confirmation should first be obtained from the supplier. In cases of doubt the marker can be visually compared with samples held or laboratory tests can be carried out. 3. TNZ M/12: 1998 AS/NZS :2017 has been published replacing Standard (AS) : 1992 upon which TNZ M/12: 1998 is based. Consultation is scheduled to commence in 2017 with manufacturers/ suppliers and other interested parties on updating TNZ M/12: 1998 to reflect the new standard. While the consultation process is underway the interim approval dates for Raised Pavement Markers that comply with TNZ M/12: 1998 have been extended to 31/1/2019 to enable: Manufacturers to undertake testing to demonstrate compliance with the revised specification. Suppliers to reduce their stocks that comply with the current specification. SP/NM12: NOTES FOR RAISED PAVEMENT PARKERS Page 8 of 13

9 TNZ M/12 Notes :2007 TABLE 1 CERAMIC MARKERS TYPE S Apex BRAND LABEL ON MARKER TYPE OBTAINED BY LEVEL 18 Radial Spokes on base of marker Ceramic Dome surface adhesion Britesite (NZ) Ltd 11 Dale Rd RD3 Drury SP/NM12: NOTES FOR RAISED PAVEMENT PARKERS Page 9 of 13

10 TABLE 2 REFLECTIVE RAISED PAVEMENT MARKERS TYPE S BRAND Apex LABEL ON MARKER APEX UNIVERSAL INC MODEL 921 Stimsonite C80 AW white) C80 BW (one way white) Stimsonite C80 AY C80 BY (one way Stimsonite C80 AR red) C80 BR (one way red) TYPE 921 white monodirectional and bi-directional White Yellow Red OBTAINED BY Traffic Safety Products Ltd 11 Dales Rd Ramarama RD 3 Drury AUCKLAND LEVEL Stimsonite 80 AW white) 80 BW (one way white) Stimsonite 80 AY 80 BY (one way White Yellow SP/NM12: NOTES FOR RAISED PAVEMENT PARKERS Page 10 of 13

11 BRAND LABEL ON MARKER Stimsonite 80 AR red) 80 BR (one way red) TYPE Red OBTAINED BY LEVEL Stimsonite MODEL 911BW (one way white) MODEL 911AW (two way white) Stimsonite MODEL 911BY (one way MODEL 911AY (two way Stimsonite MODEL 911BR (one way red) MODEL 911AR (two way red) Stimsonite MODEL 88BW (one way white) MODEL 88AW (two way white) Stimsonite MODEL 88BY (one way MODEL 88AY Series 911 Glass Faced Abrasion Resistant pavement marker White mono and bidirectional Series 911 Glass Faced Abrasion Resistant pavement marker Yellow mono and bidirectional Series 911 Glass Faced Abrasion Resistant pavement marker Red mono and bidirectional Series 88 Acrylic Plastic pavement marker White mono and bidirectional Series 88 Acrylic Plastic pavement marker Yellow mono and bidirectional SP/NM12: NOTES FOR RAISED PAVEMENT PARKERS Page 11 of 13

12 BRAND LABEL ON MARKER Stimsonite MODEL 88BR (one way red) MODEL 88AR red) Ray-O-Lite Model AA, Arc II, Ray-O- Lite DIV OF PAC-TEC INC NEWARK, OHIO Ray-O-Lite Model AA, Arc II, Ray-O- Lite DIV OF PAC-TEC INC NEWARK, OHIO Ray-O-Lite Model AA, Arc II, Ray-O- Lite DIV OF PAC-TEC INC NEWARK, OHIO Britesite Apex Model 828 AR white) Britesite Britesite Apex Model 828 AR Apex Model 828 AR (one way red) TYPE Series 88 Acrylic Plastic pavement marker Red mono and bidirectional AA Arc II White monodirectional and bi-directional AA Arc II Yellow monodirectional and bi-directional AA Arc II Red monodirectional and bi-directional White Yellow Red OBTAINED BY APEX SAFETY PRODUCTS P O Box 560 New Plymouth APEX SAFETY PRODUCTS P O Box 560 New Plymouth APEX SAFETY PRODUCTS P O Box 560 New Plymouth Britesite (NZ) Ltd 11 Dale Rd RD3 Drury Britesite (NZ) Ltd 11 Dale Rd RD3 Drury Britesite (NZ) Ltd 11 Dale Rd RD3 Drury LEVEL Interim approval, expires 31 January 2019 Interim approval, expires 31 January 2019 Interim approval, expires 31 January 2019 SP/NM12: NOTES FOR RAISED PAVEMENT PARKERS Page 12 of 13

13 BRAND Hi-Brite 213 Series Hi-Brite 213 Series Hi-Brite 213 Series LABEL ON MARKER REFLECTIVE ROAD Australia SAFETY PRODUCTS REFLECTIVE ROAD Australia SAFETY PRODUCTS REFLECTIVE ROAD Australia SAFETY PRODUCTS TYPE Series 213 Microprismatic mono directional plastic bodied White RRPM Series 213 Microprismatic mono directional plastic bodied Yellow RRPM Series 213 Microprismatic mono directional plastic bodied Red RRPM OBTAINED BY Stones Group Ltd PO Box 107 Paraparaumu Stones Group Ltd PO Box 107 Paraparaumu Stones Group Ltd PO Box 107 Paraparaumu LEVEL Interim approval, expires 31 January 2019 Interim approval, expires 31 January 2019 Interim approval, expires 31 January 2019 SP/NM12: NOTES FOR RAISED PAVEMENT PARKERS Page 13 of 13

SPECIFICATION FOR RAISED PAVEMENT MARKERS

SPECIFICATION FOR RAISED PAVEMENT MARKERS 1. SCOPE This specification covers performance requirements of retroreflective and nonretroreflective raised pavement markers which are bonded directly to the