Inspecting Occupational Safety and Health in the Construction Industry
Summary Statement
International Labor Organization handbook is designed to help provide information and training for inspectors. It contains information on key safety and health concepts and occupational safety and health issues, including managing an inspection program and performing on-site inspections.
2009
Section 4: Selection of construction enterprises and sites for inspection
-
4.1 Prior Notice of a construction project
4.2 Method for selecting construction sites to be inspected
4.3 Method for selecting construction enterprises to be inspected
4.4 Procedure to establishing the relative weights
The selection of construction enterprises and sites for inspection should follow previously defined criteria, taking into account the legislation and regulations of each country. These criteria may include many aspects which relate, directly or indirectly, to potential risks and so give information about the level of risk of each construction enterprise or project. Such criteria include:
- type of contract;
- number of contracts and subcontracts;
- number of workers;
- volume of construction work in monetary units;
- types of work;
- types of particular risk; and
- accident statistics for each enterprise compared with the national averages, where available.
Each may be applied at the construction enterprise level or at project level, and be subdivided for more detailed information (sub-criteria). For example, the number of workers should be the number of workers of the enterprise or construction project under consideration, which can be subdivided into the number of permanent workers and non-permanent workers (temporary workers, labour-only subcontracting, etc.).
This process of selecting construction enterprises or sites to be inspected is highly dependent on the national legislation obliging one or more of those involved in the construction process (in particular, the owners/clients) to inform the authorities (labour inspectorates and others depending on each country) that a construction site is to be started (Prior Notice). This is the case in all the countries of the European Union (and also elsewhere), where this obligation exists for all construction projects, under conditions listed in subsection 4.1 of this document.
This method is recommended for every country, taking into account the situation in the construction industry and the legislation of each country, which means that adjustments and simplifications may be needed.
On the other hand, other methods have been used for the selection of construction enterprises and sites for inspection, including:
- comparing the occupational accident statistics of each enterprise with the national figures for the construction industry, where this information exists and is reliable; enterprises with higher accident records than the national average should be inspected as a priority;
- casual visits by labour inspectors to the construction sites within the territory under their supervision, organised by region, city, or any other administrative division;
- a decision to inspect construction projects that involve many subcontractors and workers, considering as a good approach that the smaller enterprises (usually subcontractors) may learn from the large enterprises;
- other decisions based on the high risk involved (e.g. a scaffolding in a specific visible place in a city, which should exemplify good practice).
These methods should continue to be applied, as there will be always situations that justify their use.
Subsection 4.1 addresses the Prior Notice. Subsection 4.2 includes a method for the selection of construction sites for inspection, from which another method is also proposed in subsection 4.3 for the selection of enterprises for inspection.
4.1 Prior Notice of a construction project
A structured method for the selection of construction projects to be inspected (and consequently, also for the inspection of enterprises as referred to above) should be based on an analysis of relevant information related to each of them.
This means that the method depends on the availability and reliability of the information needed and so it is recommended that in every country the legislation require a Prior Notice.
This Prior Notice (PN) aims to inform the competent authorities (labour inspectorate and others, depending on the law of each country) that a construction site will start and so it should be prepared before any work on the site. It must be clear displayed on the construction site and be periodically updated, if necessary.
In the European Union the conditions to prepare this document varies for each country. According to the Construction Sites Directive (92/57/EEC, 1992), this Prior Notice is mandatory whenever:
- the works are scheduled to last longer than 30 working days and on which more than 20 workers are occupied simultaneously; or
- the volume of work is schedule to exceed 500 person-days (i.e. the sum of the working days of all workers).
This means, for example, that in a construction project employing 10 workers every day for 6 months (this could be for one small house), a Prior Notice is necessary, as it involves a volume of 1200 person-days (6 x 20 x 10 = 1200), assuming 20 working days per month and that there are the same number of workers every day), even though the first condition is not fulfilled (i.e. the period of time is more than 30 days, but no more than 20 workers are occupied simultaneously).
The minimum content of this Prior Notice, according to the mentioned EU Directive, is presented in the following Table 1, together with notes. However, in many countries, other information has been included in this document to take into account the situation in the construction industry in each country (e.g. the safety experts acting on behalf of the constructor, other than the safety and health coordinators).
Table 1: Content of the Prior Notice
| (1) Date of forwarding to the authorities; |
| (2) Exact address of the construction site; |
| (3) Client(s) including name(s) and address(es); (while for private projects the client is easy to identify, for public projects the client will depend on the legislation applicable) |
| (4) Type of project; (including a description of the project to enlighten the type of hazards involved and taking into account the working environment; the details of this description is important to Labour Inspectorates to decide whether they should inspect or not the construction site in view of the hazards it may involved) |
| (5) Project supervisor(s) including name(s) and address(es); (client’s representative and so an agent of the client) |
| (6) Coordinator(s) for safety and health matters during the project preparation stage (design phase), including name(s) and address(es); (new stakeholder acting on behalf of the client – he is an agent of the client for the design phase) |
| (7) Coordinator(s) for safety and health matters during the project execution stage (construction phase), including name(s) and address(es); (new stakeholder acting on behalf of the client – he is an agent of the client for the execution phase) |
| (8) Date planned for start of work on the construction site; (including the temporary works, as for the social installations) |
| (9) Planned duration of work on the construction site; (the client should base this duration on a real planning of the project that should be prepared by their agents involved pre-construction phase – project supervisor, designer, coordinator for safety and health) |
| (10) Estimated maximum number of workers on the construction site; (this corresponds to the peak of the normal distribution of labour on the construction site; this maximum number of workers is obtained from the planning of the construction project, usually, made by the Constructor) |
| (11) Planned number of contractors and self-employed persons on the construction site; (includes all subcontracting chain and this information should be given separately as for the workers of constructors, labour-only contractors, temporary workers, self-employed, etc. ) |
| (12) Details of contractors already chosen. (in some countries, this has been required just for the constructors and sub-constructors) |
Moreover, many countries have added details to clarify its content (e.g. listing the number of self-employed workers separately, or subtracting labour-only subcontractors from the number of sub-constructors).
The Prior Notice is a responsibility of the client (or owner), although some information to include in it should be obtained from the constructor. In some countries, the law also calls for a written declaration of acceptance by all those included in this Prior Notice, in particular those parties that are external to the owner’s set-up, namely the safety and health coordinators.
It is also the author’s belief that, where appropriate, this declaration should also refer to the feasibility of the time established for the project to be executed. This is important for supervisors, designers and safety and health coordinators, due to the influence it has on safety and health (a short time means a concentration of workers and potential incompatibility among simultaneous jobs, making accidents more likely). Other information that should be added (or just included as an attachment to the Prior Notice) relates to the method for selecting construction projects to inspect (e.g. the table referred in subsection 4.2).
This Prior Notice is to be presented, according to the mentioned EU Directive, before the construction site starts work (and not before the design phase), and so during the design phase there is a lack of information about the projects that are being developed, except in some “design-build” or PPP contracts (see 2.2 - Key construction concepts). Although in some EU countries there are penalties for the non accomplishment of the duties of the designers, the competent authorities cannot intervene during this phase as they have no information about them. There may be an opportunity for the authorities to analyse the designs during the construction phase, although this is rare.
Moreover, when the construction site closes, it should be required a Final Notice with the information in the Prior Notice (including the annexe) updated (or the last update of the Prior Notice that has been sent to the authorities according to the national law). It should also inform the competent authorities that the construction site has closed. This Final Notice allows a better selection of the enterprises to be inspected, as stated in subsection 4.3.
It is strongly recommend that specific forms be prepared for both the Prior Notice and the Final Notice, including the necessary means for sending them by electronic means (e.g. e-mail) to the competent authorities. This simplifies the processing of the information in both these documents, and consequently allows a better and simpler selection of construction sites and enterprises to be inspected.
4.2 Method for selecting construction sites to be inspected
The method presented below is based on the information contained in the Prior Notice (or the Final Notice, if it exists), which may include (as an attachment) other information needed for the implementation of the proposed method.
This additional information includes the following: type of contract; number of contracts and subcontracts; number of workers; volume of construction work in monetary units; types of work; types of particular risk.
These criteria may be used in isolation or in combination for a single construction site. All these criteria should be analysed in terms of the hazards they may involve (e.g. the construction of a bridge involves higher risks than the construction of a small building). A combination of more than one of these criteria is recommended. Each criterion should be weighted.
For this purpose, two levels are proposed:
- summary evaluation (1st level); and
- detailed evaluation (2nd level).
Table 2 lists possible criteria for the summary evaluation (1st level). Table 3 list possible criteria and sub-criteria for the detailed evaluation (2nd level) providing better information and so it should be followed whenever possible.
Table 2: Possible criteria for the selection of construction sites (1st Level)
| Construction Site: | Reference/Date | ||||||||||
| Nr. | Criteria | Data or Remarks (1) | Wi (2) (1 - 5) | Ai - Assessment(3) | Weighted Eval. Ei (4) | INFO N. (5) | |||||
| 0 | 1 | 2 | 3 | 4 | 5 | ||||||
| 1. | General information | ||||||||||
| 1.1. | Organizational flowchart and human resources on site | ||||||||||
| 1.2. | Past behaviour on OSH of each of the main stakeholders | ||||||||||
| 1.3. | OSH-MS (ILO-OSH 2001) implemented on site | ||||||||||
| 1.4. | Type of contract | ||||||||||
| 1.5. | Type of construction project | ||||||||||
| 2. | Volume of work in monetary units (total) | ||||||||||
| 3. | Number of contracts and subcontracts | ||||||||||
| 4. | Number of workers (maximum) | ||||||||||
| 5. | Type of works involved | ||||||||||
| 6. | Types of particular hazards involved | ||||||||||
| 7. | Free | ||||||||||
| 8. | Free | ||||||||||
| Totals (number of possible points, cases evaluated with 0, 1, …5 and total weighted points) - > | |||||||||||
| Evaluation of the Construction Site - > | |||||||||||
Table 3: Possible criteria for the selection of construction sites (2nd Level)
| Construction Site: | Reference/Date | |||||||||||
| Nr. | Criteria | Data or Remarks (1) | Wi (2) (1 - 5) |
Ai - Assessment(3) | Weighted Eval. Ei (4) | INFO N. (5) | ||||||
| 0 | 1 | 2 | 3 | 4 | 5 | |||||||
| 1. | General information | --- | -- | -- | -- | -- | -- | -- | --- | |||
| 1.1. | Organizational flowchart and human resources on site | --- | -- | -- | -- | -- | -- | -- | ||||
| a) | Suitability and sufficiency of the OSH resources on site | |||||||||||
| b) | Description of documented tasks of those with OSH responsibilities at the management level | |||||||||||
| c) | Documented identification and number of worker 's representatives according to the law | |||||||||||
| d) | Description of documented tasks for worker's representatives and means provided to accomplish them | |||||||||||
| e) | Free | |||||||||||
| f) | Free | |||||||||||
| 1.2. | Past behaviour on OSH of each of the main stakeholders | |||||||||||
| a) | Owner | |||||||||||
| b) | Designers | |||||||||||
| c) | Project supervisors | |||||||||||
| d) | OSH Coordinators or Owner's OSH expert | |||||||||||
| e) | Constructor(s) | |||||||||||
| f) | Constructors' OSH experts | |||||||||||
| g) | Free | |||||||||||
| 1.3. | OSH-MS (ILO-OSH 2001) implemented on site | |||||||||||
| 1.4. | Type of contract (tick below just one) | --- | -- | -- | -- | -- | -- | -- | --- | |||
| a) | Design-Bid-Build (DBB) | -- | -- | -- | -- | -- | -- | |||||
| b) | Design-Build (DB) | -- | -- | -- | -- | -- | -- | |||||
| c) | Developer-Constructor | -- | -- | -- | -- | -- | -- | |||||
| d) | Design-Build-Operate-Maintain (DBOM/BOT) | -- | -- | -- | -- | -- | -- | |||||
| e) | Design-Build-Finance-Operate (DBFO) | -- | -- | -- | -- | -- | -- | |||||
| f) | Design-Build-Own-Operate (DBOO/BOO) | -- | -- | -- | -- | -- | -- | |||||
| g) | Free | -- | -- | -- | -- | -- | -- | |||||
| 1.5. | Type of construction project (tick below just one) | --- | -- | -- | -- | -- | -- | -- | --- | |||
| a) | Building | -- | -- | -- | -- | -- | -- | |||||
| b) | Bridge | -- | -- | -- | -- | -- | -- | |||||
| c) | Viaduct (including under and over passages) | -- | -- | -- | -- | -- | -- | |||||
| d) | Roads and highways | -- | -- | -- | -- | -- | -- | |||||
| e) | Dams | -- | -- | -- | -- | -- | -- | |||||
| f) | Water supply and sewage drainage | -- | -- | -- | -- | -- | -- | |||||
| g) | Free | -- | -- | -- | -- | -- | -- | |||||
| 2. | Volume of work in monetary units (total) | % | ||||||||||
| 2.1. | Labour, including labour-subcontracting | |||||||||||
| 2.2. | Material, including incorporated equipment | |||||||||||
| 2.3. | Equipment (non incorporated, like cranes, etc.) | |||||||||||
| 2.4. | Subcontracts (work-performed based) | |||||||||||
| 2.5. | Free | |||||||||||
| 3. | Number of contracts and subcontracts | % | ||||||||||
| 3.1. | Contracts (i.e. contractors coordinated by the client) | |||||||||||
| 3.2. | Subcontracts (work-performed based) | |||||||||||
| 3.3. | Subcontracts (labour-only) | |||||||||||
| 3.4. | Successive chain of subcontracts (2nd and lower levels) | |||||||||||
| 3.5. | Free | |||||||||||
| Construction Site: | Reference/Date | |||||||||||
| Nr. | Criteria | Data or Remarks (1) | Wi (2) (1 - 5) |
Ai - Assessment(3) | Weighted Eval. Ei (4) | INFO N. (5) | ||||||
| 0 | 1 | 2 | 3 | 4 | 5 | |||||||
| 4. | Number of workers (maximum) | % | ||||||||||
| 4.1. | Permanent workers | |||||||||||
| 4.2. | Temporary workers (time-based) | |||||||||||
| 4.3. | Labour-subcontracting workers | |||||||||||
| 4.4. | Other workers engaged by subcontractors | |||||||||||
| 4.5. | Free | |||||||||||
| 5. | Types of work involved | --- | -- | -- | -- | -- | -- | -- | --- | |||
| 5.1. | Excavation | |||||||||||
| 5.2. | Earthworks | |||||||||||
| 5.3. | Construction | |||||||||||
| 5.4. | Assembly and disassembly of prefabricated elements | |||||||||||
| 5.5 | Conversion or fitting-out | |||||||||||
| 5.6. | Alterations | |||||||||||
| 5.7. | Renovation | |||||||||||
| 5.8. | Repairs | |||||||||||
| 5.9. | Dismantling | |||||||||||
| 5.10. | Demolition | |||||||||||
| 5.11. | Upkeep | |||||||||||
| 5.12. | Maintenance (Painting, cleaning works) | |||||||||||
| 5.13. | Drainage | |||||||||||
| 5.14. | Free | |||||||||||
| 6. | Types of particular hazards involved | --- | -- | -- | -- | -- | -- | -- | --- | |||
| 6.1. | Burial under earth-falls (particularly if more than 1,50 m) | |||||||||||
| 6.2. | Engulfment in swampland | |||||||||||
| 6.3. | Falling from a height (particularly if more than 3 m) | |||||||||||
| 6.4. | Ionizing radiation | |||||||||||
| 6.5. | Work near high voltage power lines (close to 5 meters) | |||||||||||
| 6.6. | Work near railway lines (close to 2 meters) | |||||||||||
| 6.7. | Work exposing workers to the risk of drowning | |||||||||||
| 6.8. | Work on wells, underground earthworks and tunnels | |||||||||||
| 6.9. | Work carried out by divers having a system of air supply | |||||||||||
| 6.10. | Work in caisson with a compressed-air atmosphere. | |||||||||||
| 6.11. | Work involving the use of explosives. | |||||||||||
| 6.12. | Assembly or dismantling of heavy prefabricated components | |||||||||||
| 6.13. | Free | |||||||||||
| 7. | Free | |||||||||||
| 7.1. | Free | |||||||||||
| 7.2. | Free | |||||||||||
| 8. | Free | |||||||||||
| 8.1. | Free | |||||||||||
| 8.2. | Free | |||||||||||
| Totals (number of possible points, cases evaluated with 0, 1, …5 and total weighted points) - > | ||||||||||||
| Evaluation of the Construction Site - > | ||||||||||||
(1) Data or remarks = Information related to the criteria.
(2) Wi Weight of the criteria i rated out between 1 and 5: Wi= 1, means “least important” or “little influence on the potential risks involved”; Wi= 5, means “absolutely important” or “great influence on the potential risks involved”.
(3) Ai = Assessment of each criteria i rated out between 0 and 5: Ai = 0 means “little influence on the potential risks involved” or “little attention is required”; Ai = 5 means “great influence on the potential risks involved” or “great attention is required”.
(4) Ei = Weighted evaluation of each of the criteria i.
(5) INFO - A reference (sequential) number in this column means the reference to a document that supports the evaluation, e.g., notes, comments, etc..
Each country may adopt or adapt different criteria and/or sub-criteria to accommodate its own practice and situation. A detailed definition of each criterion should be attached to the tables.
Each of the criteria should be weighted (Wi) between 1 and 5, with 1 meaning “least important” or “little influence on the potential risks involved” and 5 “most important” or “great influence on the potential risks involved”. Wi represents the weight of the criterion i from 1 to n (number of criteria considered). These weights should be defined following the procedure referred in subsection 4.4.
For each construction site, an assessment of the data related to each of these criteria should be analysed and evaluated. Each of the criteria should be rated (Ai) between 0 and 5, where 0 means “little influence on the potential risks” or, where applicable, “no attention is required” and 5 means “great influence on the potential risks involved” or, where applicable, “special attention is required”. Therefore, Ai represents the assessment of the criterion i from 0 to 5, where higher figures means a higher risk construction site.
For example, the assessment (Ai) should be higher (close to five) where many particular risks are estimated to be involved and/or the data related to the criteria may reveal a higher probability for the occurrence of risk (e.g. high number of temporary workers compared with the total number of workers on site). On the other hand, Ai should be close to zero (or even zero) if the data related to the criterion reveals that no or lesser attention is required (e.g. if there is an occupational safety and health management system implemented, than little or no attention may be required).
The weighted evaluation of each of the criteria (Ei) and the evaluation of the construction site (E) in terms of percentage (total weighted points obtained divided by the total possible points), are obtained using the following formulae, where “n” is the number of criteria checked:
The weighted evaluation of each “2nd level” criteria is obtained by the formula (3) below, and the weighted evaluation of each group of sub-criteria to be transferred to the corresponding “1st level” criteria, is obtained by the formula (4), where “m” is the number of the sub-criteria of each group.
These formulae are similar to those presented above, but using the letter “k” instead of “i” to mean the items of the 2nd level. For example, while Wi means the weight of criterion “i” of the first level (summary evaluation), Wk means the weight of criterion “k” of the second level (detailed evaluation).
For example, in a construction site where only two criteria or sub-criteria are used with W1 = 3 and W2=4, and assessments A1 = 2 and A2 = 5, respectively, the evaluation of this construction site (E) would be: E = 74%, i.e., (3 x 2 + 4 x 5) / [(3 + 4) x 5] = 26 / 35 = 0,74 x 100 = 74%.
The column referred to as “INFO” (information) in the above tables, may be used to record a reference number (e.g. sequential number) referring to a document that supports the evaluation (e.g., notes, comments).
Using this method for the different construction projects under the supervision of a labour inspectorate (or delegation for a region or city), those to be inspected as a priority should be those with higher percentages, i.e. those where more risks are estimated to be involved.
Key points to be inspected at the construction site level
Table 2 and Table 3 above give also the main key points to be inspected at the construction site level. The use of checklists like those presented in these tables, aims to help the labour inspectors to perform the inspections in a systematic way.
4.3 Method for selecting construction enterprises to be inspected
There are many different methods for selecting construction enterprises to be inspected, including decisions based on one or more of the criteria referred to in 2 above, but taking into consideration the information related to the enterprise instead of a specific construction project.
However, the following ways to select construction enterprises to inspect may be considered:
- Analysis of the occupational accident statistics of each enterprise;
- Analysis of all the evaluations of the construction sites of each enterprise.
The first method (selection based on accident statistics) should be used whenever there is a well defined official statistic system implemented in the country and the information given by each enterprise follows the same procedures of the official information and accuracy is assured.
In some countries this information may not be easy to obtain from official bodies, especially for individual enterprises, for reasons including confidentiality. However, the labour inspectorates may use their in-house information about each enterprise based on the occupational accidents that are reported to them in accordance with national law (usually, the fatal and severe accidents).
In this method, all enterprises may be grouped into different levels according to the accident statistics they have reported, using the OSH statistic indicators as referred to in the Resolution of the Sixteenth International Conference of the Labour Statisticians (ILO, 1998), which are summarised in subsection 8.3.
Those construction enterprises with higher OSH indicators in the past year (or a group of past years taken together, say 3 years) than the national average for the construction industry, will be given priority for inspection. This may also be more detailed if it uses subgroups based on the type of construction project (building, bridges, roads, etc.), for these involve different levels of risk.
The second method (analysis of all the evaluations of the construction sites of each enterprise) uses the information of the Prior Notice (or the Final Notice, if it exists) and the attachment to it. This method may be better than the previous one, as it combines statistical indicators with information specific to each enterprise.
This method follows a similar procedure to the one referred above for the selection of construction sites. Table 4 and Table 5, respectively, for the 1st and 2nd levels, may be used for this purpose, in which most of the criteria are the same, but refer to the entire enterprise instead of a single construction project. However, some criteria were added. Each country may adopt or adapt different criteria to accommodate practice and the situation within it. A detailed definition of each criterion should be attached to the table.
Table 4: Possible criteria for the selection of construction enterprises (1st Level)
| Construction Enterprise: | Reference Year(s) | ||||||||||
| Nr. | Criteria (All the information should be referred to the mentioned reference years) |
Data or Remarks (1) | Wi (2) (1 - 5) | Ai - Assessment(3) | Weighted Eval. Ei (4) | INFO N. (5) | |||||
| 0 | 1 | 2 | 3 | 4 | 5 | ||||||
| 1. | General information | --- | -- | -- | -- | -- | -- | -- | --- | ||
| 1.1. | Organizational flowchart and human resources | ||||||||||
| 1.2. | Knowledge of the past behaviour on OSH of each of the enterprise | ||||||||||
| 1.3. | Net profit (total, positive or negative) | ||||||||||
| 1.4. | OSH management system (ILO-OSH 2001) implemented | ||||||||||
| 1.5. | Statistics of occupational accidents | ||||||||||
| 1.6. | Free | ||||||||||
| 2. | Number of contracts of each type (total) | ||||||||||
| 3. | Number of construction projects of each type (total) | ||||||||||
| 4. | Volume of work in monetary units (average per year) | ||||||||||
| 5. | Number of subcontractors (average per year) | ||||||||||
| 6. | Number of workers (average per year) | ||||||||||
| 7. | Number of accidents, fatal and non fatal, by causes (total) | ||||||||||
| 8. | Free | ||||||||||
| 9. | Free | ||||||||||
| Totals (number of possible points, cases evaluated with 0, 1, …5 and total weighted points) - > | |||||||||||
| Evaluation of the Construction Site - > | |||||||||||
Table 5: Possible criteria for the selection of construction enterprises (2nd Level)
| Construction Enterprise: | Reference Year(s) | ||||||||||
| Nr. | Criteria (All the information should be referred to the mentioned reference years) |
Data or Remarks (1) | Wi (2) (1 - 5) | Ai - Assessment(3) | Weighted Eval. Ei (4) | INFO N. (5) | |||||
| 0 | 1 | 2 | 3 | 4 | 5 | ||||||
| 1. | General information | --- | -- | -- | -- | -- | -- | -- | --- | ||
| 1.1. | Organizational flowchart and human resources | ||||||||||
| a) | Suitability and sufficiency of the OSH resources | ||||||||||
| b) | Description of documented tasks of those with OSH responsibilities at the management level | ||||||||||
| c) | Documented identification and number of worker 's representatives according to the law | ||||||||||
| d) | Description of documented tasks for worker's representatives and means provided to accomplish them | ||||||||||
| e) | Free | ||||||||||
| 1.2. | Knowledge of the past behaviour on OSH of each of the enterprise | ||||||||||
| 1.3. | Net profit (total, positive or negative) | ||||||||||
| 1.4. | OSH management system (ILO-OSH 2001) implemented | ||||||||||
| 1.5. | Statistics of occupational accidents (>3 days absence) | ||||||||||
| a) | Number of accidents | ||||||||||
| b) | Incidence rate | ||||||||||
| c) | Frequency rate | ||||||||||
| d) | Severity rate | ||||||||||
| e) | Days lost per accident | ||||||||||
| 1.6. | Free | ||||||||||
| Construction Enterprise: | Reference Year(s) | |||||||||||
| Nr. | Criteria (All the information should be referred to the mentioned reference years) |
Data or Remarks (1) | Wi (2) (1 - 5) | Ai - Assessment(3) | Weighted Eval. Ei (4) | INFO N. (5) | ||||||
| 0 | 1 | 2 | 3 | 4 | 5 | |||||||
| 2. | Number of contracts of each type (total) | % | --- | -- | -- | -- | -- | -- | -- | |||
| 2.1. | Design-Bid-Build (DBB) | |||||||||||
| 2.2. | Design-Build (DB) | |||||||||||
| 2.3. | Developer-Constructor | |||||||||||
| 2.4. | Design-Build-Operate-Maintain (DBOM/BOT) | |||||||||||
| 2.5. | Design-Build-Finance-Operate (DBFO) | |||||||||||
| 2.6. | Design-Build-Own-Operate (DBOO/BOO) | |||||||||||
| 2.7. | Free | |||||||||||
| 3. | Number of construction projects of each type (total) | --- | -- | -- | -- | -- | -- | -- | ||||
| 3.1. | Building | |||||||||||
| 3.2. | Bridge | |||||||||||
| 3.3. | Viaduct (including under and over passages) | |||||||||||
| 3.4. | Roads and highways | |||||||||||
| 3.5. | Dams | |||||||||||
| 3.6. | Water supply and sewage | |||||||||||
| 3.7. | Rehabilitation works (renovations, alterations, etc.) | |||||||||||
| 3.8. | Free | |||||||||||
| 4. | Volume of work in monetary units (average per year) | --- | -- | -- | -- | -- | -- | -- | ||||
| 4.1. | Labour, including labour-subcontracting | |||||||||||
| 4.2. | Material, including incorporated equipment | |||||||||||
| 4.3. | Equipment (non incorporated, like cranes, etc.) | |||||||||||
| 4.4. | Subcontracts (work-performed based) | |||||||||||
| 5. | Number of subcontractors (average per year) | |||||||||||
| 5.1. | Subcontracts (work-performed based) | |||||||||||
| 5.2. | Subcontracts (labour-only) | |||||||||||
| 5.3. | Free | |||||||||||
| 6. | Number of workers (average per year) | |||||||||||
| 6.1. | Permanent workers | |||||||||||
| 6.2. | Temporary workers (time-based) | |||||||||||
| 6.3. | Non national workers (permanent or temporary) | |||||||||||
| 6.4. | Number of nationalities of the non national workers | |||||||||||
| 7. | Number of accidents, fatal and non fatal, by causes (total) | --- | -- | -- | -- | -- | -- | -- | ||||
| 7.1 | Falls from height (from floors, scaffoldings, roofs, etc.) | |||||||||||
| 7.2. | Caught in/between (malfunction of machinery, etc) | |||||||||||
| 7.3. | Struck by (falling objects, etc.) | |||||||||||
| 7.4. | Cave in | |||||||||||
| 7.5. | Electrocution (power lines, power tools, etc) | |||||||||||
| 7.6. | Other causes | |||||||||||
| 7.7. | Free | |||||||||||
| 8. | Free | |||||||||||
| 8.1. | Free | |||||||||||
| 8.2. | Free | |||||||||||
| 9. | Free | |||||||||||
| 9.1. | Free | |||||||||||
| 9.2. | Free | |||||||||||
| Totals (number of possible points, cases evaluated with 0, 1, …5 and total weighted points) - > | ||||||||||||
| Evaluation of the Construction Site - > | ||||||||||||
All the information in these tables should be for the reference years (e.g. previous year, or the last 3 years taken together or on average).
Some additional information related to each construction enterprise may be needed to evaluate a specific criterion. This is the case, for example, of the OSH management system that the enterprise may have implemented in a formal way, where a “letter of recognition” should be available, i.e., an “official” document proving that the system conforms to the national or tailored guidelines (preference should be given to those systems that were implemented based on the national or tailored guidelines following the ILO-OSH 2001 guidelines and recognised by an accredited body).
The implementation and formulae of this method are the same as for selecting of construction sites for inspection (subsection 4.2).
Using this process for the different construction enterprises under the supervision of a labour inspectorate (or delegation for a region or city), those to be inspected as a priority should be those with higher percentages, i.e. those which are estimated to involve more risks.
Key points to be inspected at the construction enterprise level
Table 4 and Table 5 above give also the main key points to be inspected at the construction enterprise level. The use of checklists like those presented in these tables, aims to help the labour inspectors to perform the inspections in a systematic way.
4.4 Procedure to establishing the relative weights
In the multi-criteria methods (like those used in this document for the evaluation of construction enterprises and sites), the weights of each of the criteria (and/or sub-criteria) have a major influence on the evaluation process.
In view of this, it is recommended to establish these weights in relative terms, by comparing each of the criteria with each of the others (i.e., by pairs) and decide which is more important than the other. This reduces significantly the subjectivity on the weights.
This procedure should be used among all the criteria and/or sub-criteria of the same group. For example, the criteria and/or sub-criteria in first level of the checklists included in this document for the evaluation of construction enterprises or sites, forms a group and so their relative weights is important to assure. Moreover, each of the criteria in the second level checklist is subdivided in a number of sub-criteria and so each of these criteria forms a different group for which the relative weights should also be assured.
For this purpose, comparing the criteria A with criteria B (or sub-criteria), it should be assigned the following values: 1 (one), if the criteria A is more important than criteria B; 0 (zero), if both criteria A and B have the same importance, i.e., the criteria A is as much important as the criteria B; -1 (minus one), if criteria A is less important than criteria B.
At the practical level, a square matrix (n x n) with the number of criteria and/or sub-criteria (those to be compared) placed in both lines and columns should be organised. In this matrix each element Vij (interception of each line with each column) means the value (level of importance) of the criteria i compared with the criteria j.
It should be noted that the value assigned when comparing A and B is the symmetric of the value when comparing B and A (i.e., for example, if A is more important than B, then B is less important than A)4. Summing the values assigned to each of the criteria in lines, i.e. Vi = ΣVij j= 1 to n, the most important criteria will be the criteria with the highest value Vi (i.e. Vmax), summing the positives and negatives values, and the less important criteria will be the lowest value Vi (i.e. Vmin). Based on these values, the relative weights of each of the criteria (Wi) will be given by the following formula that converts the values Vi to the scale of 1 to 5 above mentioned5:
The following example may help to clarify this procedure, where 10 criteria are to be weighted in relative terms. The correspondent matrix 10 x 10 is shown in Table 6, where the criteria A was compared to each of the other criteria (B to J) in line one, the criteria B was compared with the criteria C to J, and so on.
Table 6: Example of the definition of relative weights of the criteria and sub-criteria
In this example, the criteria D is less important than the criteria E as the value assigned is -1 (interception of line D with column E) and consequently the value of E compared with D is 1 (interception of line E with column D). The values within the dashed triangle are all the symmetric values of those on the right.
The value of each of the criteria is then obtained by summing all values in each of the lines (Vi). The highest value obtained is 9 and the lowest -9 and so the most important criterion in this example is the criteria E and the less important is the criteria C. The relative weights (Wi), within the scale of 1 to 5, were then obtained using the formula above, rounded to the nearest tenths decimal place.
_________________________________________
4 Mathematically, this matrix is called anti-symmetric matrix, where Vij= - Vji.
5 A good approach to define these relative weights is to ask to as many as possible labour inspectors to fulfill this matrix for each group of criteria and/or sub-criteria to be weighted. The weight of each of these groups would be the average or the median obtained for each of these groups.
