News

Environmental Control Requirements for Physicochemical Laboratories

Release time:

2026-03-12 13:32

Environmental control in the physicochemical laboratory is crucial for ensuring testing accuracy, equipment stability, and personnel safety, as different functional areas have varying requirements for environmental parameters.

I. Ventilation System Requirements

Local exhaust ventilation : Fume Hood Face Velocity 0.3–0.8 m/s; one unit for every 2–3 workstations; omnidirectional fume hoods are used for localized exhaust above instruments; ventilation hoods are installed for high‑temperature equipment.

Ventilation on all sides : General laboratory ventilation 8–12 air changes per hour; 10–15 air changes per hour in the chemical handling area; 8–10 air changes per hour in the reagent storage area. The airflow is supplied from above and exhausted from below.

Make-up air system The make-up air volume equals the exhaust air volume. 70–80%, delivered after primary filtration.

2. Temperature and Humidity Control Requirements

Region

Temperature requirements

Humidity requirements

General Physical and Chemical Laboratory

18–28°C

30–70%

Chemical Operations Area

18–26°C

45–65%

Instrumental Analysis Area

20–25°C

40–60%

Precision Instrument Room

20–25°C

45–55%

Balance Room

20–25°C

45–60%

Standard Solution Room

20–22°C

45–55%

Reagent Storage Area

15–25°C

30–60%

The precision instrument area is equipped with independent air conditioning, and key areas are continuously monitored and recorded.

3. Cleanliness Requirements

Cleanliness Level The general physicochemical laboratory is classified as Class 100,000 to 300,000, the instrumental analysis area as Class 10,000 to 100,000, and the precision instrument room and balance room as Class 10,000.

Control measures : New air system with primary filter +Use medium-efficiency filters and install filtration in critical areas; maintain positive pressure of 5–10 Pa in the instrument area and negative pressure of -5 to -10 Pa in the chemical operation area; personnel must change shoes and wear cleanroom garments.

4. Differential Pressure Control Requirements

Pressure Differential Setting : The pressure difference between cleanrooms and non-cleanrooms shall be ≥10 Pa; between cleanrooms of different classes, the pressure difference shall be 5–10 Pa; the instrument room shall be maintained at +5–10 Pa relative to the corridor; and the chemical operation area shall be kept at -5 to -10 Pa relative to the corridor.

Differential Pressure Monitoring Install differential pressure gauges in critical areas, equip them with alarm functionality, and record data daily.

5. Lighting System Requirements

Illuminance Standards : General Operation Area 300–500 lux; 500–750 lux in the precision operation area; 300–500 lux in the instrument analysis area; 400–600 lux in the balance room; 150–250 lux in the reagent storage area.

Light Source Requirements Color Rendering Index Ra≥80, color temperature 4000–5000K, flicker-free. Use sealed cleanroom luminaires in clean areas.

6. Vibration Control Requirements

Sensitive areas : Balancing Room, Precision Instruments Area, Optical Instruments Area.

Control measures : Keep away from vibration sources (roads, elevators, air conditioning units); install a separate concrete foundation for the observation deck; equip precision instrument tables with vibration isolation devices; conduct vibration tests in critical areas.

VII. Electromagnetic Interference Control

Sensitive instruments : Nuclear magnetic resonance, electron microscopy, precision electrochemical analyzers.

Control measures The critical instrument room is equipped with electromagnetic shielding; it features an independent grounding system with a resistance of ≤1Ω; it is located away from high‑power equipment and is fitted with power line filters.

8. Special Area Environmental Requirements

Balance Room Independent enclosure with stable temperature and humidity, positive pressure dust prevention, vibration‑proof platform, and protection from direct sunlight.

Precision Instrument Room Strict control of temperature and humidity, positive pressure, Class 10,000 cleanliness, vibration and electromagnetic interference protection, independent air conditioning. 24-hour operation.

Chemical Operations Area Good ventilation, negative pressure, corrosion‑resistant surfaces, emergency showers and eyewash stations, fire and explosion protection.

Reagent Storage Area Cool, dry, well‑ventilated storage with leak‑proofing measures, temperature and humidity monitoring, and segregation of incompatible reagents.

9. Environmental Monitoring

Daily Monitoring Temperature and humidity, pressure differentials, and ventilation status are recorded daily, with continuous monitoring in critical areas.

Regular verification Cleanliness, ventilation performance, and temperature and humidity uniformity must be inspected at least once a year.

recommend News