The Urban Road Safety Plan

(PSSU): the case study of Brescia

Cagliari, 10-12 maggio 2012

(PSSU): the case study of Brescia

Eng. Margherita CADEI

PhD student in “Places and times of the city and territories”

University of BresciaFaculty of Engineering - DICATA

margherita.cadei@ing.unibs.it

INTRODUCTION

Urban Road Safety Plan (Piano Della Sicurezza Stradale Urbana – PSSU) has been

introduced in Italy in 2001

(Ministry of the Public Works Circular n.3698 “Piani della sicurezza stradale urbana –

Linee guida per la redazione”, Rome, June 8th 2001)

BRESCIA (Middle-sized city; population: about 200.000 people; surface: about 90

km2)

First PSSU elaborated in 2009

PSSU: a planning tool to manage road

INPUT 2012 – Cagliari 10-12 may 2012 Eng. Margherita Cadei – University of Brescia

PSSU: a planning tool to manage road

safety at local level (urban areas) in an

organic and systemic way.

Based on road accident data analysis, it is

able to detect the road accident problems

on the urban road network and to offer

objective criteria to make choices.

Before: decisions about road safety based

on extemporary choices or warnings coming

from the population.

A PSSU’s main document (Piano Direttore) contains:

- aggregate analysis of the road accident data;

- detection of the network “Black spots”;

- definition of quantitative objectives and list of actions/strategies to be implemented;

- quantification of costs/benefits;

- definition of the monitoring process and coordination of the plan.

One of the most important purpose of a PSSU consists in making lists of critic

INPUT 2012 – Cagliari 10-12 may 2012 Eng. Margherita Cadei – University of Brescia

One of the most important purpose of a PSSU consists in making lists of critic

sites where infrastructural interventions are more urgent (“Black spots”).

It’s important to use adequate indicators to express the level of risk of the

network segments.

A PSSU’s main document (Piano Direttore) contains:

- aggregate analysis of the road accident data;

- detection of the network “Black spots”;

- definition of quantitative objectives and list of actions/strategies to be implemented;

- quantification of costs/benefits;

- definition of the monitoring process and coordination of the plan.

One of the most important purpose of a PSSU consists in making lists of critic

INPUT 2012 – Cagliari 10-12 may 2012 Eng. Margherita Cadei – University of Brescia

One of the most important purpose of a PSSU consists in making lists of critic

sites where infrastructural interventions are more urgent (“Black spots”).

It’s important to use adequate indicators to express the level of risk of the

network segments.

A PSSU’s main document (Piano Direttore) contains:

- aggregate analysis of the road accident data;

- detection of the network “Black spots”;

- definition of quantitative objectives and list of actions/strategies to be implemented;

- quantification of costs/benefits;

- definition of the monitoring process and coordination of the plan.

One of the most important purpose of a PSSU consists in making lists of critic

INPUT 2012 – Cagliari 10-12 may 2012 Eng. Margherita Cadei – University of Brescia

One of the most important purpose of a PSSU consists in making lists of critic

sites where infrastructural interventions are more urgent (“Black spots”).

It’s important to use adequate indicators to express the level of risk of the

network segments.

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In Brescia: ROAD ACCIDENT RATE (for each “homogeneous road segment i”):

Instead of calculating the road accident rate for road segments belonging to single

itineraries and instead of comparing the segments’ rate with two threshold values

(CNR,1998) in Brescia each road segment rate is compared with the average

value calculated for the road functional class to which the road segment belongs

(Maternini, 2000).

INPUT 2012 – Cagliari 10-12 may 2012 Eng. Margherita Cadei – University of Brescia

Id Road segment Ti

21 VIA MILANO 2,71

44 VIA CROCIFISSA 2,38

35 VIA ZIMA 2,34

50 P.LE SPEDALI 2,32

13 VIA CHIUSURE 2,30

49 VIA DAL MONTE 2,26

20 VIA MILANO 2,23

40 V.LE PIAVE 1,94

… … …

This indicator is able to express the risk related to

road safety: it puts into relation the number of

accidents, the road segment length and the amount

of traffic.

FAULTY ASPECT: Inaccuracy inherently contained

in the Istat road accident data (Tiboni, 2004)

The exact localization is not always possible;

Uniform distribution of the incomplete data!

SOME CRITICALITIES ABOUT THE ELABORATION OF THE PSSU:

ENDOGENIC FACTORS EXTERNAL FACTORS

- quality of the Istat road accident data:

- imprecise mapping introduces a

systemic error in the road accident

rate calculation;

- late delivery of the Istat data

makes unfeasible the monitoring of

the actions (PSSU life time spans 2

years)

- PSSU is just a “mandatory task”: it

is elaborated but not actually

implemented;

- lack of a strong policy towards the

road safety issues:

- inadequate resources

assignment for the

INPUT 2012 – Cagliari 10-12 may 2012 Eng. Margherita Cadei – University of Brescia

years)

- disaggregate analysis

methodologies based on road

accident scenarios/collisions

diagrams cannot be easily applied

- the Ministry Guidelines are, in some

parts, vague/incomplete:

- cost/benefit analysis;

- the “participated plan process” is

not sufficiently promoted

assignment for the

implementation plans;

- scarce coordination among

the technical departments in

delivering the road safety

projects/plan updating

SOME CONCLUSIONS

There are still some aspects that makes road safety planning/implementation

difficult;

it is hoped a wider application of the good practices available in

literature/resarches in this field;

it is hoped a review/enhancement of the present Ministry guidelines;

a stronger integration between the road safety and the already existing

INPUT 2012 – Cagliari 10-12 may 2012 Eng. Margherita Cadei – University of Brescia

a stronger integration between the road safety and the already existing

urban/mobility planning tools should be promoted.

The Urban Road Safety Plan (PSSU):

Cagliari, 10-12 maggio 2012

:: Thank you for your attention ::

The Urban Road Safety Plan (PSSU):

the case study of Brescia

Eng. Margherita CADEI

PhD student in “Places and times of the city and territories”

University of Brescia

Faculty of Engineering - DICATA

margherita.cadei@ing.unibs.it