Mechanical Pencil

Material Composition Assumptions

A standard mechanical pencil weighing approximately 20 grams consists of several petroleum and mineral-derived components. The polystyrene or polypropylene plastic barrel represents the largest component at roughly 12 grams or 60% of total weight. Metal components including the steel spring mechanism, aluminum ferrule, and brass sleeve collectively contribute about 4 grams or 20% of the product mass. The synthetic rubber eraser accounts for approximately 2 grams or 10% of weight. Graphite-clay lead mixture and plastic lead refill casings make up the remaining 2 grams or 10% of the mechanical pencil’s total composition.

Manufacturing Geography

The majority of mechanical pencils are produced in East Asian manufacturing centers, particularly China, which accounts for over 70% of global production. This concentration occurs due to established supply chains for plastic injection molding equipment, abundant graphite mining operations, and integrated metal processing facilities. Chinese manufacturing facilities operate on an electricity grid with relatively high carbon intensity at 555 gCO2e per kilowatt-hour, significantly impacting the carbon footprint of energy-intensive processes like plastic injection molding and metal stamping operations.

Regional Variation

Manufacturing Region	Grid Intensity	Estimated CCI Score	Adjustment vs Default
China	555 gCO2e/kWh	52	Baseline
Germany	366 gCO2e/kWh	44	-15%
Japan	462 gCO2e/kWh	48	-8%
India	708 gCO2e/kWh	60	+15%
Costa Rica	35 gCO2e/kWh	36	-31%

Provenance Override Guidance

1. Electricity consumption data and renewable energy certificates for plastic injection molding and metal stamping operations at the manufacturing facility.

2. Transportation records documenting shipping distances and modes from raw material suppliers to final assembly locations.

3. Material composition specifications with exact plastic resin types, metal alloy compositions, and graphite source documentation.

4. Packaging material inventories including plastic blister packs, cardboard backing, and lead refill container specifications.

5. End-of-life processing data for manufacturing waste streams including plastic trimming recycling rates and metal scrap recovery percentages.

Methodology Notes

• The CCI score represents cradle-to-gate emissions for one complete mechanical pencil including initial lead refills and primary packaging materials.

• Scope 1 emissions predominantly reflect fuel combustion during plastic injection molding and metal forming processes at manufacturing facilities.

• Scope 2 emissions capture electricity consumption for factory operations including assembly line equipment and quality control testing procedures.

• Scope 3 emissions encompass upstream material extraction, graphite mining, petroleum refining for plastic resins, and transportation logistics.

• The functional unit assumes normal consumer usage patterns with periodic lead refill replacement over the product’s operational lifetime.

• Consumer use phase emissions are excluded as mechanical pencils require no energy input during normal writing activities.

• End-of-life disposal impacts are not included due to varying regional waste management infrastructure and recycling program availability.

• Eraser replacement frequency varies significantly among users and is excluded from the baseline assessment.