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This paper aims to present the framework for a model that can be used to estimate the production rate, activity duration, total fuel use, and total pollutants emissions from earthwork activities. A case study and sensitivity analysis for an excavator performing excavations are presented.

The tool is developed by combining the multiple linear regressions (MLR) approach for modeling the productivity with the EPA's NONROAD model. The excavator data were selected to build the productivity model, and emission factors of all type of pollutants from NONROAD model were used to estimate the total fuel use and emissions.

Results indicate that the excavator productivity model had high precision and accuracy, low bias, with trench depth and bucket size are in the model, it can explain 92 per cent variability of productivity rate data, and can be used as the basis for estimating the fuel quantities that will be required and the total expected pollutant emissions for the project.

The estimating tool proposed in this paper will be an effective means for assessing the fuel consumptions and air emissions of earthwork activities and will allow equipment owners or fleet managers, policy makers, and project stakeholders to evaluate their construction projects. The tool will help the contractors to estimate the fuel quantities and pollutant emissions, which would be valuable information for a preliminary environmental assessment of the project.

Although there are already methods and models for estimating productivity rate and emissions for heavy duty diesel (HDD) construction equipment, there currently is not a means for doing all of these at once.

This paper aims to present a synergistic approach that combines both construction and environmental expertise to lay the groundwork for a model that can be used to estimate the productivity rate and emissions from construction equipment activities.

The proposed estimating tool is developed by combining the productivity rate model from a reliable construction estimating data sources and the calculation algorithm employed by the EPA's NONROAD model. In order to develop productivity models, simple earthwork activities involving bulldozer, excavator, and dump truck were selected.

The MLR approach proved to be a useful alternative for estimating productivity rate of three pieces of equipment. The MLR models for the productivity rate can explain high percentage of the variability in the data. The models are good to be used as a benchmark for estimating NO_X and PM emissions from some certain types of construction equipment performing earthwork activities. The productivity rate from this model (lcy/hr) is used with emission factors (g/hp‐hr) from EPA's NONROAD model to estimate the total emissions.

The estimating tool proposed in this paper will be an effective means for assessing the environmental impacts of construction activities and will allow equipment owners or fleet managers, policy makers, and project stakeholders to evaluate more sustainable alternatives. The tool will help the contractor to estimate the total expected pollutant emissions for the project, which would be valuable information for a preliminary environmental assessment of the project.

Although there are already methods and models for estimating productivity for construction equipment, there currently is not a means for doing estimates of air pollutant emissions at the same time, particularly for NO_X and PM.

This paper aims to investigate the behaviour determinants towards cash waqf for productive purposes between two different classes of Muslims: the upper-middle class and the lower-middle class.

Under the Theory of Planned Behavior framework, this study modified previous literature to investigate the determinants of two Muslim classes’ behaviour towards cash waqf for productive purposes. A structural equation model was applied to test the hypothesis, and an in-depth interview was conducted to explain the findings further.

The behaviour of participating in cash waqf for productive purposes differs between the two Muslim segments. Upper-middle-class Muslims’ intentions will not necessarily consider subjective norms, even though they will consider religiosity as their deciding factor. Meanwhile, this study found different results on the influence of attitude, religiosity and subjective norms to intention in the lower-middle-income group. Other attributes such as perceived behaviour control, knowledge, trust and perceived benefits show positive and significant effects on the intention for both income classes of Muslims.

The current findings may not accurately reflect ideal conditions due to the low level of waqf literacy and actual participation of Muslims in cash waqf for productive purposes. Researchers can conduct further studies based on other criteria, such as gender, age, education level or area of residence, using experimental or simulation methods to complement the research.

This study’s findings can support policymakers and related waqf stakeholders to set strategies for cash waqf literacy and participation by providing more detailed information about the differences in Muslims characteristics based on the income classes.

This study specifically modifies the behavioural framework to investigate differences in the behaviour of two classes of Muslims towards their participation in cash waqf for productive purposes in Indonesia.