CHEMICAL ENGINEERING TRANSACTIONS  
 

VOL. 57, 2017 

A publication of 

 
The Italian Association 

of Chemical Engineering 
Online at www.aidic.it/cet 

Guest Editors: Sauro Pierucci, Jiří Jaromír Klemeš, Laura Piazza, Serafim Bakalis 
Copyright © 2017, AIDIC Servizi S.r.l. 

ISBN 978-88-95608- 48-8; ISSN 2283-9216 

Occupational Safety and Health in Highway Maintenance 
Yards: an Approach Suitable to Face Special Criticalities 

Romano Borchiellinia, Corrado Ciriob, Elisabetta De Cillisc, Paolo Fargione*c, Luisa 
Maidac, Mario Patruccoc 
aDipartimento di Energia – DENERG- Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129, Torino, Italia 
bProcura della Repubblica di Savona, Piazza Angelo Barile 1, 17100, Savona Italia 
c
Dipartimento di Ingegneria dell’Ambiente, del Territorio e delle Infrastrutture -DIATI-, Politecnico di Torino, Corso Duca 

degli Abruzzi 24, 10129, Torino, Italia  
paolo.fargione@polito.it 

On the request of Prosecutor Office, the Authors carried out a research work to define the extent of the 
Occupational Safety and Health - OS&H criticalities affecting the highway maintenance yards, in normal and 
special scenarios where hazardous freights are involved. The high number of work related accidents in 
maintenance/improvement yards, often characterized by dramatic Severity Rates, requires a special Risk 
Assessment and Management. The paper summarizes the results of a research leading to identify the main 
parameters directly or indirectly conditioning the design and safety of the highway maintenance yards. We 
developed a schematization of yard typologies and contexts, upon which a thorough Risk Assessment and 
Management becomes possible. Moreover, an original Accident Analysis Technique provided precious 
support to the study, filling the gaps of information on the Standards violations of some accident databases. 
Finally, the paper discusses some innovative Safety Control measures for different highway scenarios. 

1. The context and OS&H problems in highway maintenance yards 

The Italian Highway System covers more than 6000 km, with 1800 km of tunnels, bridges and viaducts. This 
involves the need of systematic maintenance and special interventions, due to the highly variable Italian 
climatic conditions, imposing additional wear to structures and materials of large part of the network. 
Additional deterioration factors, such as mean altitude a.s.l. and traffic load, affect some stretches: Table 1 
summarizes the “total” and “heavy vehicles” traffic rates. 

Table1: Italian highway Traffic rate (source Italian Association of Highway and Tunnel Companies - Aiscat) 

Cumulative data January-March 2015 (millions of vehicles per km) 
Italian highway stretches 

(companies) Total 
Heavy 

vehicles 
Italian highway stretches 

(companies) Total 
Heavy 

vehicles 
Autostrade per l’Italia 9340.1 2307.4 Centro Padane 215.2 74.5 
Traforo Monte Bianco 2.43 0.85 Brescia-Padova 1134 321.2 
Traforo S.Bernardo 1.54 0.15 C.A.V. 369.3 95.6 
R.A.V. 24.2 6.6 Brennero 959.8 284.2 
S.I.T.A.F. 78.3 21.1 Autovie venete 521.3 169.1 
S.A.V. 78.8 17.3 Autostrada dei fiori 240.7 63.2 
A.TI.VA. 113.2 19.4 Aut.le della Cisa 136.3 41 
Asti-Cuneo 29.6 7.1 S.A.L.T. 352.2 79.7 
S.A.T.A.P. A 4 511 128.2 S.A.T. 38.7 8.5 
S.A.T.A.P. A 21 426 147.7 Strada dei parchi 459.1 63.5 
Torino-Savona 177.9 130.9 Tang.le di Napoli 221 18.3 
Milano Serravalle- MI.Tang.li 320.9 65.7 Aut. Meridionali 353.3 32.8 
Società di progetto BREBEMI 51.9 12.2 Consorzio Aut. Siciliane 330.4 52 
Tang.le Esterna di Milano 4.5 1.0 Total 16491.7 4169.2 

                               
 
 

 

 
   

                                                 
DOI: 10.3303/CET1757053

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Please cite this article as: Borchiellini R., Cirio C., De Cillis E., Fargione P., Maida L., Patrucco M., 2017, Occupational safety and health in 
highway maintenance yards: an approach suitable to face special criticalities, Chemical Engineering Transactions, 57, 313-318   
DOI: 10.3303/CET1757053 

313



The presence of dangerous goods further increases the importance of maintenance and the criticality of the 
maintenance yards: dangerous goods are 10.5 % of the total transported freights, and 52 % travel by road 
(Italian Federchimica data). In Figure 1 (left) the dangerous goods circulating in the 28 EU countries in 2013. 
Eurostat data evidence a 8.4 % decrease of dangerous goods transportation on road in Italy, but the problem 
still remains concerning (approx. 7.000 t per kilometer), and a careful safety analysis of the traffic - yards 
interferences is still a priority. 
From January 2008 to May 2013, 5562 non-fatal and 87 fatal accidents (the 1.5 % of the total) occurred in the 
Italian highway maintenance yards (source National Institute for Work Injury Insurance - Inail). In Figure 1 
(right) the main causes of accidents in the Italian highway maintenance yards (from the same source). 

 
 

Figure 1: Dangerous goods circulating in the EU countries in 2013- source Eurostat (left); accidents typologies 

occurred in Italian highway maintenance yards (right).  

A comparison between Italian and USA data from 2003 to 2007 (sources Occupational Safety and Health 
Administration - OSHA, and Census of Fatal Occupational Injuries - CFOI), confirmed the similarity in terms of 
hazard factors and criticalities of highway maintenance yards. Workers run over causes 50 % of the fatal 
accidents: run overs are due to equipment and vehicles belonging to the firm in charge of the site (54 %), or to 
other companies involved in the work (46 %) (Pegula, 2010). The Inail database provides no information on 
the accidents due to traffic - maintenance sites interference; according to the OSHA database the run overs of 
maintenance workers due to traffic amount to approx. 30 % of the total.  
The Authors also referred to the National Statistical Institute - ISTAT and Italian Automobile Association - ACI 
data, to investigate the violations of the Traffic Laws, and the result is impressive: the total number of 
sanctioned violations in 2013 is more than 900,000 (560,000 for excessive speed, 35,000 general for reckless 
driving). No direct correlation is at present possible, but countermeasures are certainly necessary. 
The OS&H situation resulting from the analysis of accident data demonstrates the general lacking Culture of 
Safety in terms of understanding of the interactions between cultural and contextual variables in a given 
scenario, and the effect they have on safety. 

2. Risk Assessment and Management in highway maintenance yards 

Risk can be defined (Borchiellini et al., 2015) as the potential of losing something of value: life, health, 
property or environment can be compromised by a given action, activity or inaction (whose probability can be 
estimated) involving a Hazard Factor which can cause the Unwanted Event and related losses. 
Risk Assessment: the evaluation -pivotal to define a correct prioritization of Risk Management- of the levels of 
risk involved in a situation. 
Risk Management: all the activities giving rise to the elimination / minimization of risks, through prevention 
(technical, organizational or procedural steps to reduce -and possibly set to zero- the frequency of occurrence 
or the contact factor), or protection (general or personal), to mitigate the severity of the possible damage. 
An accurate Risk Assessment in complex situations, such the one under exam, requires a systematic 
approach, based on a rigorous schematization of the various contexts, scenarios and types of maintenance 
and improvement yards, to bring into evidence the problems which may be added to those typical of similar 
temporary or mobile construction sites (see Table 2). 
  

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Table 2: Highway maintenance yards: main parameters affecting the characteristics, design and safety (in 

addition to those typical of a similar temporary or mobile construction site) 

parameter typical criticalities examples 
type and 
characteristics 
of the yard 

urgency, importance, extension, 
and duration of the activities; 

emergency repairs or activities planned with no 
special haste; radical renovations and modifications; 

frequency of occurrence: 
exceptional/occasional/systematic;  

parts maintenance due to accidents; pavement 
repair/renovation,...; 

position and evolution in space: 
stationary / mobile yards;  

localized embankment maintenance; painting of 
lane markings; 

special yards;  not directly related to the highway normal use; 
“internal” 
parameters 

unique features of each situation; in case of emergency repairs, the seasonal 
conditions can require different design approaches 
even for the same activity; 

available areas and special 
constraints, possible interference 
of contemporary activities;  

the limited areas usually available can be further 
reduced, e.g. by overbridges; interference problems 
rise due to other yards, e.g. junctions,…; 

additional problems;  poor design in terms of maintainability, typical of the 
less recent stretches; equipment, materials and 
parts supplying, emergencies management,...; 

“external” 
parameters 

orographic & geomorphological 
characteristics, mean weather 
conditions, traffic load in general, 
and light / heavy traffic "seasonal" 
changes,..;  

different traffic load, steeper stretches, straights and 
bend radii, windy conditions introduce criticalities in 
vehicle velocities, difference in speed between light 
- heavy vehicles, and modify the importance and 
frequency of maintenance and of interferences; 

peculiar site characteristics, such 
as tunnels, viaducts, etc.. 

interventions in tunnels can require special 
ventilation and fittings, criticalities from old linings,...; 

typologies of goods transported  dangerous goods traffic conditions the importance 
and criticality of the maintenance yards.  

Every maintenance yard presents unique features, and requires a special Prevention through Design - PtD 
(National Institute for Occupational Safety and Health – NIOSH) approach for the Risk Management. 
The proposed schematization, together with an in depth investigation of the intermediate and Root causes of 
the occurred accidents, can support the Risk Management phase, and contribute to identify the most suitable 
design for each special situation. The analysis of occurred accidents is still often limited to a general statistical 
approach, possibly involving subjective assumptions. Nevertheless, some innovative investigation techniques 
are nowadays available, among them the Computer-aided Cause Consequence for Prevention - CCCP 
technique (Luzzi et al., 2015), an original evolution from a combination of Fault Tree Analysis - FTA and Event 
Tree Analysis – ETA, based on the System approach (Reason, 2000). The CCCP approach provides help 
also in the discussion of the best control measures to interrupt the chain of causes of the event. Figure 2, from 
a real case, depicts the logical CCCP analysis flow, and provides an example of the achievable results. 
 

 

Figure 2: Results of the CCCP technique applied to a real event occurred in 2006. 

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Table 3 summarizes some possible Risk Management actions on the factors that can increase, in the case of 
highway maintenance yards, the Risks typical of similar temporary or mobile construction sites. 

Table 3: Possible Risk Management actions to minimize the peculiar risks of highway maintenance yards 

 factor technical measures other (organization & procedures) 

In
te

rn
a

l 
R

is
k

s
 

ED emergency solutions special for the context; special emergency procedures; 

FC 
in typically limited areas, throughout analysis 
of the risk of interference and introduction of 
physical/non physical safety barriers; 

introduction of strict work procedures; 
interruption of work in case of difficult 
environmental conditions (e.g. poor visibility); 

P 
PtD approach special for the operation, 
including techniques, technologies and 
equipment selection, etc.; 

special inspection and maintenance of 
equipment and fittings, special supervision and 
IFT (Information, Formation and Training); 

n 
reduction to a minimum of the number of 
exposed workers, through a mechanization 
level as high as technically possible; 

do; 

E
x

te
rn

a
l 

R
is

k
s
 

ED collective protection systems (barriers, Truck 
Mounted Attenuators,…); 

speed limits;  

FC 
scheduling of the highway maintenance 
activities to minimize the need of interventions 
in critical traffic or weather conditions; 

special organization of activities, shifts, and of 
trips to and from the yard;  

P 

minimization of the number of highway 
maintenance interventions, through improved 
design choices and adoption of innovative 
materials and techniques; 

safety lanes, traffic detour, speed limits, yard 
signage coherent with the general provisions 
of D.I. 04/03/2013, etc.; 

n as suggested for the internal risk management; as suggested for the internal risk management. 

3. Some results of the research work 

The safety of both workers and third parties, in general, and more so in the case of particularly risky and 
complex activities, imposes to consider both Safe Work Organization, and the Maximum Safety 
Technologically Achievable criteria. In coherence with the provisions of law (89/391 EEC Directive, enforced in 
Italy by D.Lgs.81/08), Article 6 General Obligations on employers, c.2. states: “The employer shall implement 
the measures … necessary for the safety and health protection of workers, including prevention of 

occupational risks and provision of information and training, as well as provision of the necessary organization 

and means) on the basis of the following general prevention principles: … (e) adapting to technical progress”.  
These criteria should be applied both to operations in the maintenance yard, and to the context in which the 
maintenance site is located. Asides from the well-known guidelines and good practices for the “normal” linear 
yards safety, and taken into account the contents of Table 3, the following pages discuss some examples of 
technological improvements on the safety of stretches and yards, which already proved effective abroad, and 
are finding growing use also in the Italy (EU Commission under the transport RTD programme, 1998). 

3.1 Examples of new technologies to support the safety of highway and of the maintenance yard 
workers  

3.1.1. Innovative materials and laying technologies for the highway pavement 
Innovative materials and laying technologies for the pavements are nowadays available: this is a promising 
theme for study and research on bituminous binders, aggregates, additives and related products. The main 
targets are technical and economic efficiency, pavement duration, and environmental issues (Nösler, 2008).  
Fiber or steel-net reinforced pavements, fiber reinforced asphalt-concrete flexible and high resistance 
pavements in Polymer modified Binders, and other solutions already provide in some cases important benefits 
in resistance to stresses induced by heavy vehicles (Abtahi et al., 2010; Yildirim, 2007), or reducing cracking 
and cracks propagation (Xu et al., 2010). Together with excellent surface characteristics, these advanced 
materials and technologies improve adherence, limit aquaplaning or splash & spray phenomena and 
degradation by deicing, and ensure good soundproofing. Their use for new highway stretches, or to replace 
the existing ones, can enhance the system availability, reducing the number of repair/renovation interventions, 
i.e. the need of maintenance yards. Hence, the FC value decreases, thanks to the increase of the Mean Time 
Between Failures - M.T.B.F. (Mean Time To Failure - M.T.T.F. + Mean Time To Repair - M.T.T.R.).  
Even so, a preliminary Risk Analysis is essential, to define the expectable M.T.T.R. value, and make sure not 
to have introduced new hazard factors for the maintenance yard workers. 

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3.1.2. Technical improvements for the management of possible distributed traffic  yard interferences  
In case of mobile linear yards, the usual segregation of the working areas from the traffic, based on Jersey 
barriers, involves that the progressive modification of the yard area makes also necessary the modification of 
the barriers layout. The traditional procedure (Figure 3 left) implies that the yard workers manually unfasten 
each module of the barrier, lift it up and move it to the new position by means of a crane; finally, it is necessary 
to reconnect the module to the already moved barrier. Workers and equipment operate in immediate proximity 
of the regular traffic; signage, light signals and flagman become necessary to draw the attention of the 
highway users. This operation is one of the most critical for the safety. The adoption of mechanized “Barrier 
Zippers” for Jersey barrier transfer (Rathbone, 2000) makes possible a significant Risk reduction for workers 
and users, see Figure 3 right; Table 4 summarizes the results of a Preliminary Hazard Analysis – PHA. 

  

Figure 3: Barrier transfer: traditional procedure (left), mechanized “Barrier Zipper” technique (right). 

Table 4: Extract of a Preliminary Hazard Analysis on traditional vs “Zipper” barrier movement activity 

Hazard (traditional 
technique) 

Cause (1) Risk reduction achieved by 
use of “Barrier Zipper”  

Note 

workers and 
flagmen run over by 
vehicles unrelated 
to the yard; 

regular traffic in 
proximity of the 
working areas; 

limited exposure of the 
workers;  

during the barrier tranfer with 
the “Barrier Zipper” technique, 
no workers operate in 
unprotected areas; 

yard equipment 
struck by vehicles 
unrelated to the 
yard; 

unprotected 
yard equipment 
and vehicles 
during the 
barrier tranfer; 

minimization of unprotected 
yard equipment and vehicles; 

the Barrier Transfer Machine is 
the sole equipment necessary, 
and operates safeguarded by 
the barrier already tranferred; 

crushing; handling of 
heavy loads; 

hightly mechanized activity 
carried out from cabin and 
safe areas; 

the “Barrier Zipper” does not 
imply manual operations such 
as unfastening/fastening of 
each module; 

(follow)    
(1) some parameters typical of the Italian highway scenarios can further increase the Risk for both yard 

workers and users. 

The Risk reduction possible through the adoption of the described solution results from:  
 the reduction of P, thanks to the continuous barrier covering the whole length of the yard. The safety 

of drivers is also increased, thanks to the clarity of the situation;  
 the reduction of FC, since the yard workers operate exclusively from the safe side of the barrier; 
 the reduction of n, thanks to the mechanization of the system. 

3.1.3. Technical improvements for the management of possible localized traffic  yard interferences 
In case of stationary maintenance yards of limited extension and duration, where no Jersey barriers are 
present, the protection of the yard from vehicles irruption is possible by the positioning of obstacles of 
adequate size and mass (usually some heavy equipment or trucks). Such an improvised approach, even if 
effective to the purpose, can worsen the seriousness of the consequences for the impacting vehicle driver. 
Some Truck Mounted Attenuators - TMA are now available, specially designed to improve the yard protection 
and reduce the collateral damages. Though occasional maintenance interventions are often carried out 
overnight, the critical number of fatal accidents due to the yard presence proves that lighting conditions 
(together with the weather ones) heavily influence the driver’s perception of the yard area (Arditi et al., 2007). 
TMA devices can also contribute to enhance the yard identification and the anticipation of driver’s reactions 
(Bham et al., 2010). Figure 4 shows the basic idea. 

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Figure 4: Truck Mounted Attenuator (left), and crash test results (right).  

Granted that, in this case also, the discussed measures signaling the yard are necessary, the Risk reduction 
possible through the adoption of the TMAs results from the reduction of FC, since the possibility of irruption of 
vehicles out of control into the working area is limited; asides, the safety of drivers is increased. 

4. Conclusion 

The peculiarity of the highway maintenance yards requires a special Risk Assessment and Management, 
particularly relevant in the case of Italian scenarios, whose peculiar characteristics somehow increase the 
common temporary yard Risks. The research work made available some interesting results: 
a. a through categorization of the different maintenance yards, of pivotal importance to define the different 

scenarios, and to identify the most suitable safety measures necessary in each situation; 
b. a critical review and some practical examples of innovative techniques and technologies currently 

available, and of their possible effects on the total system efficiency (safety included); 
More generally, the research work confirmed that at least in complex situations, among them the highway 
maintenance yards, the Risk Assessment and Management must be absolutely specific, and devoted to each 
situation requiring special Prevention through Design and Quality Management approaches. Moreover, also in 
these situations, the dissemination of the "Culture of Safety" can play a key role in the reduction of risks of 
workers and third parties. 

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