Transforming brick manufacturing in Bangladesh to promote clean air and better health

The effectiveness of energy efficiency improvements and worker incentives for coal-fired brick zigzag kilns: a randomized controlled trial on energy use and brick quality

Status

Active, not recruiting

Phases

Unknown

Study type

Interventional

Source

ISRCTN

Registry ID

ISRCTN15354089

Enrollment

300

Registered

2022-10-21

Start date

2022-10-01

Completion date

Unknown

Last updated

2025-09-08

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Inefficient operation of coal-fired brick kilns that results in substantial emissions of PM2.5, black carbon, and CO2. Other

Interventions

We will have two experimental arms: 1) technical knowledge and training (technical arm) and 2) technical knowledge and training + worker incentives (incentive arm). Kilns assigned to both arms will re

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: The unit of randomization will be brick kilns. The study subjects will include the owner and workers of the brick kiln. Inclusion criteria for brick kilns are: 1. The kiln owner is a member of the Bangladesh Brick Makers Owners Association. 2. The kiln owner operates at least one coal-fired zigzag kiln that is located in Khulna Division. 3. The kiln owner consents to participate in the study

Exclusion criteria

Exclusion criteria: 1. Participated in the pilot study 2. Took efforts on their own to adopt interventions similar to those implemented in the pilot study 3. Unwilling to be randomized to a control group 4. Already have one kiln from this owner enrolled in the trial

Design outcomes

Primary

Measure	Time frame
1. Carbon monoxide/carbon dioxide ratio (a measure of combustion efficiency measured by placing a sensor into the flue gas) 2. Specific energy consumption (the energy used in MJ for firing 1 kg of brick) measured by multiplying tons of coal consumed by the gross calorific value of the coal and dividing by total production of bricks 3. Percent of Class 1 bricks produced measured by kiln owners' self-report of total brick production and the percent breakdown by quality, as well as fieldworker calculation of fired bricks coming out of the kiln. All three primary outcomes will be collected during a 24-hour measurement visit to each kiln approximately 4 months post-intervention, which is when kiln firing reaches a steady-state.	—

Measure

Time frame

1. Carbon monoxide/carbon dioxide ratio (a measure of combustion efficiency measured by placing a sensor into the flue gas) 2. Specific energy consumption (the energy used in MJ for firing 1 kg of brick) measured by multiplying tons of coal consumed by the gross calorific value of the coal and dividing by total production of bricks 3. Percent of Class 1 bricks produced measured by kiln owners' self-report of total brick production and the percent breakdown by quality, as well as fieldworker calculation of fired bricks coming out of the kiln. All three primary outcomes will be collected during a 24-hour measurement visit to each kiln approximately 4 months post-intervention, which is when kiln firing reaches a steady-state.

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Secondary

Measure	Time frame
1. Use of financial or in-kind incentives for workers to adopt technical intervention measured at 1 month, 4 months, and 7 months. 2. Worker self-reported respiratory symptoms collected by survey at 7 months compared to baseline. 3. Specific fuel consumption (SFC) measured at 4 months by dividing total quantity of coal consumed by total number of bricks produced. 4. Tons of CO2 equivalent measured by converted the primary outcome specific energy consumption into its CO2 equivalent by applying the Intergovernmental Panel on Climate Change (IPCC) carbon emissions factor for fuel, and a carbon to CO2 conversion factor. 5. Distributional change in brick quality of all types measured by kiln owners' self-report of total brick production and the percent breakdown by quality, as well as fieldworker calculation of fired bricks coming out of the kiln. 6. Value of production measured by multiplying brick production per brick class by the median price reported per class measured at 7 months.	—

Measure

Time frame

1. Use of financial or in-kind incentives for workers to adopt technical intervention measured at 1 month, 4 months, and 7 months. 2. Worker self-reported respiratory symptoms collected by survey at 7 months compared to baseline. 3. Specific fuel consumption (SFC) measured at 4 months by dividing total quantity of coal consumed by total number of bricks produced. 4. Tons of CO2 equivalent measured by converted the primary outcome specific energy consumption into its CO2 equivalent by applying the Intergovernmental Panel on Climate Change (IPCC) carbon emissions factor for fuel, and a carbon to CO2 conversion factor. 5. Distributional change in brick quality of all types measured by kiln owners' self-report of total brick production and the percent breakdown by quality, as well as fieldworker calculation of fired bricks coming out of the kiln. 6. Value of production measured by multiplying brick production per brick class by the median price reported per class measured at 7 months.

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Countries

Bangladesh

Outcome results

None listed

Source: ISRCTN (via WHO ICTRP) · Data processed: Feb 4, 2026