| Term | Definition | 
|---|---|
| AAV | Aggregate Abrasion Value - the standard measure of an aggregate’s resistance to abrasion. | 
| Authority | The authority as defined in the Act. | 
| Bond coat | Proprietary materials certified by a Product Acceptance Scheme, generally formulated to provide cohesion between bituminous layers. | 
| CBGM base | Cement bound granular mixture – a mixture of controlled graded aggregate using cement that sets and hardens by hydraulic reaction. This is a specific type of relatively strong hydraulically bound material (HBM) typically used for base layers in composite roads. | 
| CBR | California bearing ratio - a penetration test for the mechanical strength of soils and granular materials. | 
| Composite footway, footpath or cycle track construction | A pavement comprising lean mix concrete or other hydraulically bound material (including cement bound granular mixtures) overlaid with a bituminous surface course or a bituminous surface and binder course. | 
| Composite road construction | A pavement comprising concrete, lean mix concrete, CBGM base or some other hydraulically bound granular material with a bituminous overlay of 100 mm or more. Where the bituminous overlay is less than 100 mm or there is no bituminous overlay, the pavement is considered rigid. | 
| Cut-back | See ‘stepped joint’. | 
| Cycle track | A way constituting or comprised in a highway, being a way over which the public have a right of way on pedal cycles only, with or without a right of way on foot. | 
| Deep opening | Any opening, excavation, core or trench where the depth of cover over the apparatus is greater than 1.5 m but not including openings with a depth of cover intermittently greater than 1.5 m over lengths of less than 5 m. | 
| DMRB | Design Manual for Roads and Bridges. | 
| Emergency works | Works required to prevent the occurrence of circumstances likely to cause danger to persons or property. See S52 of the Act for the formal definition. | 
| FCR | Foamed Concrete for Reinstatements. | 
| Flexible construction | A structure where the base comprises a bituminous or granular material, or a combination thereof. | 
| Footpath | A way over which the public has a right of way on foot only, not being a footway. | 
| Footway | A way comprised in a highway, which also comprises a carriageway, being a way over which the public has a right of way on foot only. | 
| Geosynthetic materials | A generic term describing a product at least one of whose materials components is made from a synthetic or natural polymer in the form of a sheet or a 3D structure and used in contact with soil or other materials in geotechnical and civil engineering applications. | 
| HBM | Hydraulically bound material – material comprising a mixture of soil and/or graded granular material with hydraulic binder and water that sets and hardens by hydraulic reaction. | 
| Immediate reinstatement | Works comprising the orderly replacement of excavated material, reasonably compacted to finished surface level, usually with a cold-lay surfacing. This technique is used when it becomes necessary to temporarily reinstate an excavation to permit immediate trafficking. | 
| Interim reinstatement | The orderly placement and proper compaction of reinstatement layers to finished surface level, including any temporary materials. | 
| Intervention | Repair to a compliant condition of a reinstatement that does not comply with the performance requirements of this Code. | 
| LA | Los Angeles abrasion value – a measure of an aggregate’s resistance to abrasion. | 
| Large diameter core | A core over 150 mm in diameter. | 
| Major works | Standard works that have been identified specifically in the undertaker’s annual operating programme or which, if not specifically identified in that programme, are normally planned at least 6 months in advance of works commencing. | 
| MCHW | Manual of Contract Documents for Highway Works. | 
| Micro trench | An opening up to 60 mm wide and over 1 m long. | 
| Modular construction | A structure where the surface comprises setts, concrete blocks, brick pavers or paving slabs etc. laid on an appropriate sub-construction. | 
| msa | Million standard axles – based on the expected traffic to be carried over 20 years. See S1.3. | 
| Narrow trench | An opening over 60 mm and up to 300 mm wide and over 1 m long. | 
| NRSWA | See "The Act". | 
| Other openings | Any opening, excavation or core that is not a micro trench, a narrow trench, a large diameter core, a small opening or a deep opening. | 
| Pen | The penetration grade of a bituminous binder. | 
| Permanent reinstatement | The orderly placement and proper compaction of reinstatement layers up to and including the finished surface. | 
| PMMA | Polymer modified mastic asphalt to BS EN 13108-6. | 
| Preferred | The favoured choice between permitted options. | 
| Product Acceptance Scheme | Product Acceptance Scheme in accordance with 100 Series of the MCHW, Clauses 104.15 and 104.16 (such as British Board of Agrément certificates). | 
| PSV | Polished Stone Value. | 
| Restricted area | Small openings, openings less than 200 mm wide or other areas where conventional compaction equipment cannot be used effectively. | 
| Rigid construction | A pavement quality concrete surface slab (that may be reinforced) which also performs as the base or a concrete base with less than 100 mm bituminous overlay. Where the bituminous overlay is 100 mm or more the pavement is considered to be composite. | 
| Road & footway structure | The surface course, binder course, base and sub-base. | 
| Small features | Frames and surface boxes smaller than 600 mm x 600 mm. | 
| Small openings | An excavation with a reinstatement surface area, excluding the apparatus surface area, up to 2 m2 in road types 0, 1 and 2 and up to 4 m2 in road types 3 and 4 and in footways, footpaths and cycle tracks, that is not a large diameter core, a micro trench or a narrow trench. | 
| SRV | Skid Resistance Value – a measure of the frictional properties of a surface using a pendulum test device. | 
| Stepped joint | A step where the reinstated binder and/or surface courses are made wider than the reinstatement below to provide higher resistance to water ingress. | 
| Street | The whole or any part of the following, irrespective of whether it is a thoroughfare: 
 | 
| Street manager | As referred to in the Act, Section 49(4). | 
| Surface treatment | A thin protective layer (e.g. surface dressing) applied to the surface to restore skid resistance and/or to seal it. This does not include high amenity or high duty surfaces, or surfaces with an aesthetic requirement. | 
| The Act | The New Roads and Street Works Act 1991 (NRSWA). | 
| Trim-line | The cut face that defines the outer edge of an excavation at the surface. | 
| Trimback | The area between the trim-line and a fixed feature and the edge of an excavation. | 
| UKAS | United Kingdom Accreditation Service. | 
| Undertaker | A person with a statutory right to execute street works or the holder of a street works licence. | 
| Verge | The area of the highway outside the carriageway (and footway if present). A verge may be slightly raised but is exclusive of embankment or cutting slopes and is generally grassed. | 
| Wheel tracking | A test to determine the resistance to deformation (rutting) of, primarily, surface courses. | 
