4。1。Working at elevation

Hazards and fatalities associated with working at an elevation have always been emphasized in the literature of construction safety。 The majority of 153 fall incidents investigated resulted from deficiencies in the use of Personal Protective Equipment (PPE)    by

Table 4

Keywords representing the generic type of rules to be checked。

up or down if the conditions are satisfied, and a number of reason- ing rules to check the conditions present in the accident scenes are

Problem keyword

Class     Description

suggested。 Each rule may deal with one or more objects, resources, locations, or actions, as well as required values and methods to be called (Goh and Chua, 2009; Jiang and Leicht, 2014), and requires a specific procedure to be checked, which resembles a generic type of check, and hence belongs to one of the four classes  introduced

Table 3

Portion of the accidents that are related to design according to accident type。

Existence 1 The whole model or a defined part of it is searched to

find an object with a special attribute

Type 1 A specific attribute field of a known object is  sought

and reported

Geometry 1 Geometric attributes of a known object is  reported Count 1 Objects with a special attribute of interest in the

whole model or a defined part are  counted

Distance 2 Physical distance between the nearest points of two

objects is calculated

Pathfinding 3 The shortest route between two points for a worker    or

machine is plotted

Source/

accident type

Fall or

falling objects

Unsafe

operation

Electric

shock

Cave in or

asphyxiation

Total

Exposure 3 The possible way that a workplace can be exposed  to

precipitation is found

H。 Malekitabar et al。 / Safety Science 82 (2016) 445–455 451

Table 5

Drivers that influence the consequences and probabilities of all kinds of accidents。

Drivers and rules Rule class and  type

of check

Driver:  Victim  Recovery (VR)

Description: Late VR due to being out of sight or access, or being far from medical services drove up the consequence of accidents of all  types

Rules to check

Existence of a helicopter pad Class 1 (existence) Size of workgroups (whether they are to work solely) Class 1 (count) Distance between workplaces Class 2 (distance)

Distance to nearest hospitals Class 3b (external data)

Access to all workplaces Class 3 (pathfinding)

Sight of workplaces over each other Class 3 (pathfinding)

Table 6

Drivers for the risk of ‘‘fall or falling objects”。

Drivers and rules Rule class and  type

of check

Driver: Fall Arrest Systems (FASs)