CHAPTER 7 Site observations of traffic infrastructure
7.6 Checklists
The checklists can be structured as gen-eral or specific. The gengen-eral lists contain the broad aspects to be considered, for which it is recommended that the audit team define the topics that should be in-corporated in the audit according to the characteristics of the project to be eval-uated and depending on the phase in which the RSA/RSI will be performed. In the same way, special aspects of the project must be identified and not listed in the formats presented in the manual.
The specific checklists contain in detail each of the aspects to be evaluated, dis-aggregating the content established in the general checklist, in order to identify the findings that affect the road safety of the evaluated project. In the specific checklists the magnitude and the risk of
the deficiency are normally assessed.
The magnitude refers to the grade of the deficiency, and it is normally ranked in three levels (very bad, bad and me-dium). For example, we can find a dete-riorated pedestrian crossing, but this de-terioration can be ranked to give an idea of the actual condition of the pedestrian crossing. The risk refers to the impact that deficiencies have on users’ safety, and it is ranked in four levels (continu-ous, frequent, sometimes and sporadic).
Given that the format presented in this handbook is general, the audit team should adjust their formats to allow them to record as much information as possi-ble for each of the items or aspects eval-uated.
7.6.3 ASPECTS TO BE ANALYSED
The audit team must carry out an evalu-ation of the key aspects that the check-lists consider from the point of view of road safety. These aspects differ ac-cording to the stage in which the RSA or RSI is being carried out.
Environment
The generalities of the project are dis-cussed, such as the function or origin, how the project is framed within the road network and for whom the road infra-structure designed will serve. This infor-mation allows an evaluation of the con-text of general project security. It is nec-essary to analyse aspects such as changes from the previous stages (if ap-plicable), drainage, climatic conditions, landscaping, services, access to proper-ties and important developments in the
environment, access to emergency vehi-cles, future extensions and/or future re-alignments, construction by stages of the project, planning by stages of the works, stability of slopes and embank-ments and compliance with technical re-quirements for signalling, road clear-ance, side areas and other users.
Infrastructure
Evaluate whether a previous RSA or RSI has been performed, which allows knowledge of aspects that require spe-cial attention and the changes that have been generated in the project. The audit team must consider additional aspects to those outlined in the handbook in ac-cordance with the characteristics of the
In this section, the corridor is analysed.
When performing an RSI, based on a field visit in combination with the con-struction drawings, we can determine the sites that may have security prob-lems. Here we analyse aspects related to visibility distances, design speed, speed limits, homogeneous sectors, ge-ometry of horizontal and vertical align-ment, overtaking, cross section, bridges and gauges, culverts and boxes, trans-verse slopes and banks, friction, defects of the pavement and slopes of inclines.
Intersections also play an important role.
The intersections must be easy to under-stand for the user, and the design should strive to use the same type of intersec-tion throughout the project, or a typology according to the types of roads that in-tersect, with the aim of preventing the user from deciphering each intersection individually, which generates insecurity and can lead to mistakes.
Special road users
Special users are pedestrians, cyclists, motorcyclists, cargo transport vehicles, public transport and road maintenance vehicles. The project environment should be evaluated with the aim of providing complete solutions for special
users. In this section, we seek to evalu-ate from the perspective of road safety whether the facilities required by these special users have been taken into ac-count and if their use allows safe travel throughout the project.
Transit and transportation
For RSA, it is highly important to know which types of users are going to use the infrastructure or which type of users are going to cross it. How traffic is distributed in time is basic to anticipating road safety problems.
One of the most important aspects in road projects is related to signage, so this must be evaluated judiciously since it is the communication language of the users with the road project to achieve safe and fluid movement. In addition to a good design, it is necessary to provide all the necessary and sufficient infor-mation to the user of a road so that he can manoeuvre safely and with sufficient advance notice. The most important as-pects to be evaluated are lighting, traffic lights, vertical signage, demarcation and road delineation, central barriers, lateral containment barriers, poles and other obstructions and finally bridges, culverts and gutters.
Table 7-5: Road aspects to be analysed when performing an RSI (MINITRANSPORTE, 2017) Aspect General topic Particular topic
Environment
General environment Weather conditions Landscaping Landscaping and terrain
Infrastructure
Corridor
Visibility and visibility distance Design speed
Horizontal and vertical alignment Speed limit/speed zoning Overtaking
Readability Rail widths Berms Bridges Culverts
Transverse slopes and banks Slip resistance
Puddles
Functional defects of the pavement Traverse slopes
Intersections
Location
Horizontal and vertical layout Visibility to and from the intersection Horizontal signage
Vertical signage Lateral banks Illumination Others
Auxiliary lanes
Length and transitions Visibility
Vertical signage and demarcation
Associate infrastruc-ture
Public and private equipment Areas of services and rest
Access to properties and urban developments Accesses for emergency vehicles
Vulnerable road
us-General topics Pedestrians
Motorcyclists
Special road users Public transport Maintenance vehicles
Other road safety as-pects
Parking lots
Provision for heavy vehicles Temporary road works
Activities on the edge of the road Rest areas
Crossing of animals Furniture
Urban landscaping
Traffic and transportation
Signage, facilities and obstructions
Illumination
General topics of vertical signalling Centre line, edge line and lane line Legibility of signals
Devices for traffic regulation Lateral zones
Barriers and defences
Visibility of barriers and defences Traffic light