The Solvent Dispensing Area (SDA) is a controlled and ventilated workspace designed specifically for:
- Receiving, measuring, and dispensing of volatile or flammable solvents (e.g., methanol, ethanol, acetone, IPA, toluene).
- Transferring solvents from large containers (drums or barrels) into smaller, accurately measured quantities for use in production or analytical processes.
Key Design Elements:
| Element | Purpose |
|---|---|
| Dispensing booth / laminar flow hood | Provides local exhaust ventilation to capture solvent vapors. Often equipped with flameproof lighting and explosion-proof fittings. |
| Anti-static flooring and grounding | Prevents static discharge during solvent transfer, reducing explosion risk. |
| Pressure differential control | Maintains negative pressure relative to adjacent clean areas to contain vapors. |
| Exhaust and supply air ducts | Ensures a minimum number of air changes per hour (e.g., 20–25) and directs solvent fumes to a safe exhaust system. |
| Safety shower and eye wash station | Provides immediate decontamination in case of accidental exposure. |
| Solvent-resistant floor drains | Safely collect accidental spills into solvent collection tanks. |
Safety Features:
- Flameproof Light.
- Continuous exhaust ventilation to keep vapor concentrations below 25% of LEL (Lower Explosive Limit).
- Automatic fire detection and suppression system (CO₂ or dry powder).
- Earthing and bonding for all metal drums, vessels, and transfer lines.
- Solvent vapor detectors with alarm and interlock features.
Environmental Controls:
- Temperature: typically 20–25°C
- Relative humidity: ≤ 60%
- Air pressure: Negative to adjacent areas
- Air filtration: HEPA filtered air if part of a cleanroom-grade operation
Example Workflow:
- Solvent drums brought from quarantine → to dispensing area.
- Drum connected to earthing line and grounded dispensing pump.
- Solvent dispensed under local exhaust ventilation.
- Measured volume transferred into clean, labeled stainless-steel or HDPE containers.
- Area cleaned, and documentation completed before next batch.
References:
- WHO GMP / EU GMP Vol. 4
- ISPE Guidelines
- NFPA (National Fire Protection Association) standards
- Schedule M (India)
- OSHA & ICH Q7 (for APIs)