# Securing Construction Workers' Data Security and Privacy with Blockchain Technology
## 3 Methodology
### Experimental Design of the Proposed Blockchain
#### 3.1.3 Deployment of Proposed Blockchain
The model functions because (i) it allows pertinent stakeholders, such as the Human resource manager, project manager, contractor, health and safety officer, regulatory bodies, inspector, and certification body, to register as members of the network to endorse the construction workers' data; (ii) construction workers' bi-data and safety data are stored and require the participants in (i) to sign and endorse the information digitally, and the governance of the network is established based on the consensus and consent of all of the stakeholders; (iii) every time information is requested by a permitted stakeholder, the smart contract (chaincode) converts it into a transaction and sends it to the ordering service through which transactions are packed into blocks; in this way, the transactions are then secured cryptographically before being added to a blockchain system to create an immutable chain of records; (iv) to further enhance the security of the information during the endorsement process, the proposed model uses a consensus algorithm to ensure complete protection of the privacy of the data; and (v) each participant (stakeholder) on the blockchain sets up a copy of the ledger to keep track of the endorsed transaction information, and the smart contract can retrieve the stored transactions from the ledgers whenever requested by the stakeholders. #### 4.1.2 Testing of Conceptual Blockchain-Based System Using the Transaction Testing Approach

To validate the functionality and effectiveness of the Hyperledger Fabric blockchain system developed for the tiling activity case study, comprehensive testing was conducted, with a significant focus on transaction verification. The primary objective was to ensure the system's reliability, data accuracy, and its ability to securely manage and store construction workers' biographic and safety data related to work-related musculoskeletal disorder (WMSD) risk assessments. Transaction testing played a crucial role in validating the blockchain's functionality and data integrity. Hyperledger Explorer, a powerful visual

Figure 7: Screenshot of part of the Transaction History API tested in POSTMAN. ization tool, was employed to facilitate the monitoring and analysis of transactions, shown in Figure 9.

Through this implementation, the blockchain demonstrated its capability to securely collect, store, and manage sensitive worker information. Each step of the data collection process, from capturing workers' biodata to assessing WMSD risks, was translated into transactions on the blockchain. These transactions were then visualized using Hyperledger Explorer, providing a clear and transparent overview of the entire process. In this testing

Figure 8: A blockchain-based model for enhancing the privacy and safety of construction workers’ information. (**i**) Membership registration; (**ii**) Information management; (**iii**) Ordering Service; (**iv**) Consensus mechanism; (**v**) Decentralized ledger of construction workers’ biodata and safety data. scenario, a total of five blocks, each containing a set of transactions, were generated. These transactions represented various interactions related to the management of construction workers' data. The involvement of three nodes in the network underlines the decentralized nature of the Hyperledger Fabric blockchain, where multiple stakeholders collaboratively maintain the integrity of the network and validate transactions. Furthermore, the presence of one chaincode emphasized the smart contract's role in governing the rules and logic for managing data on the blockchain. This comprehensive testing phase not only ensured the technical robustness of the blockchain system but also demonstrated its applicability in a real-world construction context. The blockchain system exhibited its capability to securely manage and provide access to authenticated and verified construction workers' information. The successful visualization of transactions using Hyperledger Explorer showcased the transparency and tamper-resistant nature of the data stored.