Resource, Site and Supply Chain Management

Introduction and Context

Construction projects convert designs, specifications and contractual commitments into physical assets through the coordinated use of labour, plant, materials, information, finance and temporary facilities. Resource management is therefore more than purchasing materials or allocating workers. It is the systematic planning, acquisition, deployment, control and improvement of resources so that work is safe, productive, compliant, economical and resilient.

In construction, resources are consumed in a changing environment. Access may be restricted, weather may be uncertain, drawings may be revised, productivity may vary, and suppliers may fail to deliver. A project can therefore suffer delay even when its total resources are theoretically sufficient. The central managerial problem is to ensure that the right resource is available at the right location, in the right condition, at the right time and at an acceptable total cost.

This chapter integrates labour, plant, materials, temporary works, site layout, logistics, work study, lean construction, subcontracting, procurement lead times, supply-chain resilience and responsible sourcing. The emphasis is on managerial decisions and their interaction rather than on isolated resource categories.

Learning Objectives

By the end of this chapter, the reader should be able to:

1. Prepare resource plans for labour, plant, materials and temporary works.

2. Design site layouts and logistics systems that support safe and productive operations.

3. Apply work-study methods and productivity measures to identify improvement opportunities.

4. Explain lean construction principles and apply tools such as pull planning and constraint removal.

5. Manage subcontractors, suppliers, procurement lead times and expediting activities.

6. Evaluate supply-chain risk, resilience, ethical sourcing and sustainability.

7. Use digital technologies and data responsibly in resource and site management.

1. The Resource Management System

A resource plan should be derived from the work breakdown structure, construction methods, programme and budget. For each work package, the project team should define:

• the required activities and quantities;
• the construction method and sequence;
• labour skills and crew composition;
• plant type, capacity and utilisation assumptions;
• material specifications, quantities and delivery dates;
• temporary works and enabling facilities;
• inspection, testing and acceptance requirements;
• risks, constraints and contingency arrangements.

Resource planning is iterative. At tender stage, estimates are broad and uncertain. During pre-construction, methods and quantities become clearer. During execution, actual production data should be used to revise forecasts, improve allocations and identify emerging constraints.

A useful distinction is between resource availability and resource productivity. Availability asks whether a resource exists when needed. Productivity asks how much acceptable output is obtained from the resource and the time used. A project may have adequate labour but low productivity because of congestion, poor information, repeated rework or waiting for materials.

Resource decisions should be assessed using total cost, not only purchase price. Total cost may include transport, handling, storage, inspection, wastage, downtime, maintenance, financing, disposal and environmental impacts. A cheaper material that arrives late or generates extensive waste may be more expensive in project terms.

Resource loading and levelling

Resource loading places planned resource demand against time. It can be displayed as a histogram showing, for example, the number of electricians required each week. Resource levelling modifies activity timing or methods to avoid unacceptable peaks and shortages, usually while respecting project completion requirements. Resource smoothing adjusts activities within available float so that demand becomes more even without changing the critical completion date.

These techniques involve trade-offs. Levelling may extend the programme, while overtime or additional crews may preserve the completion date but increase cost and supervision requirements. A sound decision considers critical-path effects, labour availability, fatigue, site congestion, contractual milestones and risk.

2. Labour Planning and Productivity

Labour planning concerns both quantity and capability. A labour schedule should identify trades, competence levels, crew structures, shift arrangements, supervision and expected output. Competence must include technical skill, safety training, equipment authorisation and familiarity with the specific construction method.

Labour productivity

A basic labour productivity measure is:

Labour productivity = accepted output / labour input

If output is measured in square metres and input in labour-hours, the unit is m² per labour-hour. The reciprocal is labour-hours per unit of output, often useful for estimating. For a work package with quantity Q, a planned labour coefficient h (labour-hours per unit) and available effective hours per worker per period H, the approximate number of workers required is:

N = Qh / H

This calculation assumes that the work content, crew composition and effective hours are known and that output is not constrained by plant, materials, space or preceding activities. Effective hours should exclude realistic allowances for breaks, access, preparation, coordination and unavoidable interruptions. It should not be confused with paid hours.

Worked example. A finishing package contains 1,200 m². The estimated labour requirement is 0.80 labour-hours per m². Each worker provides 36 effective hours per week. The weekly labour requirement is 960 labour-hours. If the package is planned over four weeks, the average requirement is 240 labour-hours per week, or:

N = 240 / 36 = 6.67

Thus, seven workers are required on average, subject to practical crew composition and fluctuations. Rounding upward does not guarantee completion because access, material supply and supervision may constrain production.

Productivity is influenced by method, learning, weather, design quality, site access, congestion, supervision, morale, payment systems, safety conditions, rework and the reliability of preceding work. Productivity comparisons should therefore be made cautiously. A low output rate may reflect system constraints rather than poor individual effort.

Work study

Work study combines method study and work measurement. Method study records the current process, questions each step and develops a safer or more efficient method. Work measurement estimates the time required by a qualified worker, operating at a defined performance level, under specified conditions.

Common observation techniques include:

• direct time study using a stopwatch or digital recorder;
• activity sampling, which estimates the proportion of time spent in categories through random observations;
• production studies, which compare output against resource hours;
• video analysis, used ethically and with appropriate consent;
• first-run studies, which capture actual learning and coordination effects.

A practical observation classification is productive work, contributory work and non-productive time. Contributory work, such as positioning tools or receiving instructions, may be necessary, whereas avoidable waiting and rework indicate improvement opportunities. Observations should identify system causes rather than blame workers.

3. Plant and Equipment Management

Plant selection should reflect production requirements, site conditions, safety, whole-life cost and logistical compatibility. Important criteria include capacity, reach, mobility, ground bearing pressure, fuel or energy use, reliability, operator competence, emissions, maintenance support and transport requirements.

A plant plan normally contains an equipment schedule, mobilisation dates, operator requirements, inspection records, maintenance arrangements, utilisation targets, backup arrangements and demobilisation dates. The planner should distinguish ownership, hire and subcontracted plant. Each option has implications for capital, availability, maintenance risk and flexibility.

Plant utilisation can be represented as:

Utilisation = productive operating time / available time

This ratio is meaningful only when the observation period and definitions are stated. A machine may be available but idle because materials, operators or work fronts are unavailable. Increasing utilisation is not always beneficial if it creates congestion, unsafe interaction or excessive maintenance risk.

For repetitive operations, production capacity should be checked against the limiting resource. For example, an excavation system may include an excavator, trucks and a disposal facility. Increasing excavator capacity will not improve output if trucks or disposal slots remain the bottleneck. The system should be balanced around the constraint.

Plant management also includes statutory examinations, pre-start checks, lifting plans, traffic segregation, operator certification, defect reporting and energy management. Equipment failure should be analysed through preventive maintenance and failure data rather than treated only as an isolated event.

4. Materials, Inventory and Temporary Works

Material management begins with a procurement schedule linked to drawings, specifications, quantities and the programme. Materials should be identified by required-on-site date, not merely by purchase date. The schedule should include approval, manufacture, testing, shipping, customs where applicable, delivery, inspection, storage and installation allowances.

Material quantity control should distinguish gross quantity, net installed quantity, expected waste, damage allowance and contingency. Excess ordering ties up cash and creates storage and disposal problems; insufficient ordering causes disruption and emergency procurement.

Inventory and lead time

Lead time is the elapsed time between initiating a procurement action and having an accepted resource available for use. It may include design approval, enquiry, tender evaluation, purchase order, manufacture, testing, transport, customs, unloading and inspection. Critical items should have a documented lead-time analysis and an identified owner.

A reorder point can be expressed as:

Reorder point = expected demand during lead time + safety stock

The formula assumes that demand and lead time are measured in compatible units. Safety stock is not a universal percentage; it should reflect variability, consequence of shortage, storage cost and the availability of substitutes. In project procurement, the reorder-point concept must be adapted because demand is often a planned one-time requirement rather than a continuous repetitive demand.

Materials should be protected from moisture, contamination, theft, impact and deterioration. Storage should preserve identification and traceability. The first-in, first-out principle may be appropriate for perishable or time-sensitive materials, but compatibility, curing requirements and manufacturer instructions take priority.

Temporary works

Temporary works include scaffolding, formwork, falsework, shoring, propping, hoarding, access platforms, temporary drainage, cranes bases, haul roads and temporary services. They may be removed later, but their safety and engineering significance can be greater than that of permanent elements during construction.

A temporary-works management system should define design responsibility, checking category, approval, loading limits, erection sequence, inspection, modification control and dismantling. Temporary works must be designed for actual construction loads, including wind, impact, water, construction traffic, eccentric loading and accidental conditions where relevant. Unauthorised alteration is a major control failure.

5. Site Layout and Construction Logistics

Site layout is a production-system design problem. It should support safe movement, short and reliable material flows, clear supervision, environmental control and future phases of work. Typical components include gates, security, offices, welfare, storage, fabrication areas, plant routes, pedestrian routes, lifting zones, waste facilities, emergency access, utilities and temporary drainage.

The layout process should begin with constraints: land boundaries, neighbours, existing services, topography, environmental restrictions, fire access, public interfaces and construction sequence. The team should then map major flows of people, materials, equipment, waste and information. A layout that is efficient in phase one may be unsuitable in phase three; therefore, phased layouts are often preferable.

Important principles include:

1. Separate pedestrians and vehicles wherever practicable.

2. Minimise double handling and crossing flows.

3. Place high-use facilities close to the relevant work fronts without compromising safety.

4. Provide stable, drained and adequately lit routes.

5. Locate storage according to delivery frequency, lifting requirements and protection needs.

6. Maintain emergency access and escape routes.

7. Plan for changing work fronts and temporary works.

8. Use visual controls, signage and controlled access.

Logistics planning should specify delivery windows, booking systems, vehicle sizes, unloading equipment, holding areas, traffic marshals, documentation and contingency routes. Just-in-time delivery can reduce storage but increases vulnerability to traffic, weather and supplier disruption. It should be used selectively rather than as an ideology.

6. Lean Construction and Work-Flow Reliability

Lean construction adapts lean production ideas to the uncertain, project-based and multi-organisational nature of construction. Its central concern is reliable value creation with reduced waste. Waste includes waiting, excess movement, unnecessary transport, overproduction, excess inventory, defects, rework, inappropriate processing and underused knowledge.

Lean does not mean simply working faster or reducing labour. It requires improving the production system so that work flows and commitments are reliable. Key practices include:

• value-stream mapping to visualise material and information flows;
• pull planning, in which activities are planned backward from a milestone;
• constraint analysis before work is promised;
• reliable weekly commitments by those performing the work;
• daily coordination and visual management;
• first-run studies and standard work;
• root-cause analysis of plan failures;
• continuous improvement through small, evidence-based changes.

The Last Planner approach distinguishes should, can, will, did and learned. A schedule may state what should happen, but a reliable weekly plan includes only work that can be performed because prerequisites are satisfied. Percent Plan Complete (PPC) is commonly calculated as:

PPC = number of completed promised tasks / number of promised tasks × 100%

PPC is a reliability indicator, not a direct measure of productivity or project value. A high PPC can result from making conservative promises, while a low PPC should trigger analysis of reasons such as design information, materials, labour, plant, access or preceding work.

Lean methods must be adapted to the contract and culture. Poorly implemented lean can become another reporting burden or a mechanism for transferring risk to trade contractors. Collaboration, transparent information and respect for workers are essential.

7. Subcontractor and Supplier Management

Subcontractors often perform the majority of physical work and hold essential specialist knowledge. Their management should begin before award with capability assessment. Evaluation may include relevant experience, financial capacity, technical resources, safety performance, quality systems, programme capacity, ethical practices, insurance and supply-chain dependencies.

A subcontract package should define scope boundaries, interfaces, design responsibility, access, temporary works, materials, testing, programme obligations, payment, change control, records, health and safety, environmental duties and handover requirements. Ambiguous interfaces generate claims and rework. A responsibility matrix such as a RACI chart can clarify who is responsible, accountable, consulted and informed.

Supplier performance should be monitored using indicators suited to the package, such as on-time delivery, conformity rate, response time, documentation completeness, corrective-action closure, safety performance and forecast reliability. Measures should not encourage undesirable behaviour, such as shipping incomplete orders merely to achieve an on-time metric.

Commercial relationships should combine control with collaboration. Early supplier involvement can improve design-for-manufacture, packaging, sequencing and logistics. However, collaboration does not remove the need for competition, due diligence, clear records and protection against conflicts of interest.

8. Procurement Strategy, Lead Times and Resilience

Procurement strategy determines what will be bought, when, from whom and under what commercial arrangement. Options include single or multiple sourcing, framework agreements, local or international supply, design-and-build procurement, early orders, off-site manufacture and direct purchase by the main contractor or subcontractor.

A procurement risk register should record each critical item, responsible person, required-on-site date, current status, approval dependencies, manufacturing duration, transport exposure, alternative suppliers and recovery action. Long-lead items should be identified during design, not after construction has started.

Supply-chain resilience is the ability to anticipate, absorb, adapt to and recover from disruption while maintaining critical functions. Disruptions may arise from extreme weather, conflict, cyberattack, industrial action, insolvency, disease outbreaks, regulatory changes, port congestion or quality failures.

Resilience measures include:

• mapping suppliers beyond the immediate tier;
• identifying single points of failure;
• prequalifying alternatives;
• approving technically equivalent substitutions in advance where possible;
• holding strategic, not excessive, inventory;
• using modular or standardised designs;
• diversifying transport routes and suppliers;
• maintaining accurate forecasts and open communication;
• rehearsing contingency and recovery plans.

Resilience has a cost. Multiple suppliers may reduce dependency but increase coordination and quality variation. Local sourcing may shorten transport distances but may not provide sufficient capacity or technical capability. Decisions should be based on consequence, probability, recovery time and total cost.

9. Responsible Sourcing, Governance and Ethics

Responsible sourcing addresses environmental, social and governance impacts across the supply chain. Relevant issues include legal employment, modern slavery, forced or child labour, discrimination, fair wages, occupational safety, corruption, conflict minerals, community impacts, biodiversity, carbon emissions, waste and resource depletion.

Procurement documents should include proportionate requirements, evidence expectations, audit rights, reporting duties and corrective-action procedures. Certification can provide useful evidence but should not replace independent judgement. A supplier with impressive policies may still perform poorly in practice.

Ethical procurement requires transparent evaluation criteria, segregation of duties, declaration of interests, controlled communications, documented approvals and audit trails. Emergency procurement may justify accelerated procedures but should not eliminate accountability. Gifts, facilitation payments, undisclosed relationships and manipulation of competition create legal and professional risks.

Environmental decisions should consider life-cycle effects. A material with low embodied carbon may be inappropriate if it is incompatible with the design or causes premature failure. Responsible decisions integrate durability, maintenance, reuse, recyclability, transport, local impacts and end-of-life management.

10. Digital Technologies and AI

Digital tools increasingly connect the programme, procurement schedule, site records, models, delivery bookings and resource data. Building information modelling can support quantity extraction, sequencing, spatial coordination and logistics simulation. Enterprise systems can connect purchase orders, receipts, invoices and inventory. Sensors, telematics and computer vision can provide information about equipment use, location and site conditions.

Artificial intelligence can assist with demand forecasting, anomaly detection, document classification, schedule-risk analysis and image-based progress monitoring. Its use requires reliable data, clearly defined decision authority, validation, cybersecurity and protection of personal information. AI predictions should be treated as decision support rather than unquestionable fact. Bias in training data may disadvantage workers or suppliers, while automated surveillance may damage trust and raise legal concerns.

The best digital implementation begins with a management problem and a usable workflow. Technology that produces data without ownership, action thresholds or integration may increase administrative burden rather than performance.

11. Illustrative Case: Urban Hospital Extension

Background

A fictional contractor is constructing a six-storey hospital extension on a constrained urban site. The project must maintain access to the operating hospital, has limited storage, and includes a tower crane, prefabricated façade panels and several specialist subcontractors.

Problem

During the first structural phase, deliveries arrived without coordination, trucks blocked the public road, reinforcement was stored in walking routes, and façade panels were forecast to arrive six weeks late. Weekly planning showed a PPC of 58%. The project team initially attributed the problem to subcontractor productivity.

Analysis

A logistics review mapped vehicle, pedestrian, reinforcement, concrete and waste flows. It showed that three trades shared one narrow unloading zone. Work-study observations found that steel fixers spent substantial time searching for bundles and waiting for the crane. Procurement analysis showed that façade approval was not included in the manufacturing lead-time baseline. Constraint reviews also found incomplete opening details and late survey information.

Approach and solution

The team introduced a phased site layout, a delivery-booking system and timed unloading slots. Reinforcement was tagged by zone and delivered in smaller, sequenced loads. A protected pedestrian route and a separate waste collection point were established. The façade supplier joined weekly pull-planning meetings, and design approvals were converted into explicit constraints with named owners. A second approved transport route and a limited buffer of critical façade components were arranged. Subcontractors made weekly commitments only after access, drawings, materials and preceding work were confirmed.

Outcome

After six weeks, the project recorded PPC of 86%, reduced crane waiting, and eliminated public-road obstruction. The façade forecast returned to the required installation window. Storage area was not increased; instead, delivery timing and identification improved. The team also found that some apparent labour underperformance had been caused by system-level waiting.

Learning points

1. Site congestion is often a flow-design problem rather than a motivation problem.

2. Procurement lead times include approvals and information, not only manufacturing.

3. Reliable planning depends on removing constraints before promising work.

4. Small buffers can improve resilience when they are targeted at high-consequence items.

5. Performance measures should encourage learning and expose causes, not assign blame prematurely.

12. Challenges and Limitations

Resource planning models depend on assumptions that may be wrong. Productivity rates from previous projects may not transfer because of different methods, labour markets, weather or site constraints. Resource histograms can conceal skill shortages by counting all workers as interchangeable. Lean indicators can be gamed, and digital dashboards can create false precision.

Construction supply chains also contain power imbalances. Smaller subcontractors may lack the cash flow to absorb late design changes or delayed payment. Risk transfer through contract clauses may reduce the main contractor’s apparent exposure while increasing the probability of failure elsewhere in the chain. Good management therefore requires fair allocation of risk, timely decisions and payment discipline.

Finally, optimisation of one resource can damage the whole system. Maximising plant utilisation may increase waiting elsewhere; reducing inventory may increase stoppage risk; compressing labour may increase fatigue and defects. The appropriate unit of analysis is the complete production and supply system.

13. Best-Practice Implementation Framework

A practical implementation sequence is:

1. Define the work breakdown structure, construction methods and information requirements.

2. Identify resource quantities, skills, plant, materials and temporary works.

3. Link each resource to programme activities and required-on-site dates.

4. Map site flows and design phased layouts.

5. Identify constraints, bottlenecks and long-lead items.

6. Select procurement and subcontracting strategies using total cost and risk.

7. Establish inspection, traceability, safety and ethical controls.

8. Use reliable weekly planning and measure causes of failure.

9. Review productivity through work study and first-run learning.

10. Update forecasts using actual data and maintain contingency plans.

11. Close the loop through lessons learned, supplier feedback and asset information handover.

This framework works best when responsibilities are explicit. Every critical resource, constraint and procurement action should have an owner, a required decision date and an escalation route.

Chapter Summary

Resource, site and supply-chain management is an integrated production-system discipline. Effective planning aligns labour, plant, materials, temporary works, site layout and logistics with the programme and construction method. Labour productivity must be interpreted in relation to system constraints, while plant capacity and utilisation should be balanced around bottlenecks. Materials require accurate quantities, protection, traceability and lead-time control; temporary works require formal design, checking and modification management.

Lean construction improves reliability by reducing waste, removing constraints and making realistic commitments. Subcontractor and supplier management requires clear interfaces, capability assessment, performance measurement and collaborative yet accountable relationships. Resilient procurement maps dependencies, prepares alternatives and uses targeted buffers. Responsible sourcing incorporates ethical, environmental and governance requirements. Digital tools and AI can improve visibility and forecasting, but only when supported by reliable data, human judgement, cybersecurity and clear accountability.

Key Terms

Resource loading: Placing planned resource demand against time.

Resource levelling: Adjusting activities to reduce resource peaks and shortages.

Resource smoothing: Adjusting activities within available float to improve demand stability.

Labour productivity: Accepted output per unit of labour input.

Work study: The combined use of method study and work measurement.

Plant utilisation: Productive operating time divided by available time.

Lead time: Time from initiating procurement to having an accepted resource ready for use.

Safety stock: Additional inventory held to protect against uncertainty.

Temporary works: Structures or facilities used to enable construction and later removed or altered.

Construction logistics: Planning and control of movements, storage and access on and around a site.

Lean construction: A production-system approach focused on value, flow, waste reduction and reliable commitments.

Constraint: A condition that must be satisfied before planned work can be performed.

Percent Plan Complete: The percentage of promised tasks completed as planned.

Subcontractor: An organisation contracted to perform a defined part of the construction work.

Responsible sourcing: Procurement that considers environmental, social, ethical and governance impacts.

Supply-chain resilience: The ability to withstand, adapt to and recover from disruption.

Total cost: All relevant acquisition, use, risk, handling, maintenance and disposal costs.

Pull planning: Planning backward from a required milestone using commitments by those performing the work.

Review Questions

Short Answer Questions

1. Distinguish resource availability from resource productivity.

2. What is the difference between resource levelling and resource smoothing?

3. Identify four elements that should be included in a material procurement schedule.

4. Why are temporary works subject to formal design and inspection controls?

5. What does Percent Plan Complete measure?

Long Answer Questions

1. Explain how labour, plant, materials and site logistics should be integrated in a resource plan.

2. Discuss the principles and limitations of work study in construction productivity improvement.

3. Explain how lean construction improves workflow reliability and distinguish it from simple cost cutting.

4. Develop a framework for evaluating and managing subcontractors and critical suppliers.

5. Discuss responsible sourcing and supply-chain resilience in the context of construction procurement.

Analytical / Application Questions

1. A project has adequate labour on site but persistent low output. Design a diagnostic work-study investigation and identify the data you would collect before changing crew size.

2. A critical façade component has a 16-week manufacturing lead time, uncertain approval duration and only one qualified supplier. Propose a procurement and resilience strategy, including decision gates and contingency actions.

3. Design a phased logistics plan for a constrained urban site with one access gate, a tower crane, public interface and multiple specialist trades. Explain how you would measure whether the plan improves system performance.

Multiple Choice Questions with Answers

Question 1

A project requires 960 labour-hours per week, and each worker provides 36 effective hours per week. What is the minimum whole number of workers required?

A. 24

B. 26

C. 27

D. 30

Correct Answer: C. 27

Question 2

Which statement best describes resource smoothing?

A. Adding unlimited labour to eliminate all delay

B. Adjusting activities within available float to stabilise resource demand

C. Replacing all hired plant with owned plant

D. Ordering materials only after installation begins

Correct Answer: B. Adjusting activities within available float to stabilise resource demand

Question 3

Which item is normally part of procurement lead time?

A. Only factory manufacturing duration

B. Only transport duration

C. Approval, manufacture, transport and inspection activities

D. Only the payment period after installation

Correct Answer: C. Approval, manufacture, transport and inspection activities

Question 4

What does Percent Plan Complete primarily measure?

A. The reliability of promised weekly work

B. The profitability of a subcontract

C. The embodied carbon of materials

D. The utilisation of construction equipment

Correct Answer: A. The reliability of promised weekly work

Question 5

Which action is most consistent with lean construction?

A. Making commitments before checking prerequisites

B. Increasing inventory for every material regardless of risk

C. Removing constraints before including work in a reliable weekly plan

D. Measuring only individual worker speed

Correct Answer: C. Removing constraints before including work in a reliable weekly plan

Question 6

A plant utilisation ratio is calculated as:

A. Total purchase cost divided by operating hours

B. Productive operating time divided by available time

C. Available time divided by fuel consumption

D. Output quantity divided by material quantity

Correct Answer: B. Productive operating time divided by available time

Question 7

Which is an appropriate control for temporary works?

A. Allowing unrecorded alterations by any trade

B. Using formal design, checking, inspection and modification control

C. Inspecting only after dismantling

D. Ignoring construction-stage loads

Correct Answer: B. Using formal design, checking, inspection and modification control

Question 8

What is a principal risk of just-in-time delivery on a highly uncertain project?

A. Excessive permanent storage capacity

B. Greater exposure to transport or supplier disruption

C. Elimination of all procurement coordination

D. Guaranteed reduction in total cost

Correct Answer: B. Greater exposure to transport or supplier disruption

Question 9

Which procurement practice most directly supports responsible sourcing?

A. Selecting solely on lowest initial price

B. Ignoring lower-tier suppliers

C. Including ethical, environmental and governance requirements with verification

D. Avoiding records for emergency purchases

Correct Answer: C. Including ethical, environmental and governance requirements with verification

Question 10

Why should AI-generated construction forecasts remain subject to human review?

A. AI cannot process any project data

B. Forecasts may reflect poor data, bias or uncertain assumptions

C. Human review always makes forecasts less accurate

D. AI is legally prohibited from all construction applications

Correct Answer: B. Forecasts may reflect poor data, bias or uncertain assumptions