Examination of laboratory fume hoods acc.

to the guidelines for laboratories (BGR120) [link] sub-section 11.5

In accordance with sub-section 3.1.5.1 of the guidelines for laboratories (ZH1/119), laboratories must be equipped with adequate technical ventilation facilities that are effective at all times.

Sub-section 5.3.1.1 of the guidelines for laboratories (BGR120) stipulates that any work involving gases, vapors or suspended matter in dangerous concentration or quantity may only be carried out in fume hoods.

The basis of the testing obligation for fume hoods is § 39 Para. 3 of the Unfallverhütungsvorschriften (UVV), "Allgemeine Vorschriften" (http://www.bc-verlag.de/UVVen/1/inhaltHTM) ("Safety facilities for the prevention or elimination of risks, e.g. safety lighting, fire extinguishing appliances, suction equipment, signaling equipment, standby units and emergency stops as well as ventilation systems with air purification have to be regularly serviced and have their functional reliability tested. The tests have to be carried out at least every year on safety facilities, with the exception of fire extinguishers, and at least every two years on fire extinguishers and ventilation systems.") As "suction systems", there is a relevant annual testing obligation for fume hoods acc. to UVV standard text. An extensive definition and explanation of this basic obligation took place through the supplementation of the guidelines for laboratories (BGR120) by sub-section 11.5 ("Fume hoods must be regularly serviced and their functional reliability tested and documented. An expert must carry out the test at least once a year. The annual test of the ventilation function need not take place if it is safeguarded through permanent monitoring of the individual fume hood that a dropping of the minimum volume current is displayed optically and acoustically.") An expert is a person...


"...who has sufficient knowledge in the field of fume hood testing as a result of his professional training or experience and is acquainted with the relevant national work protection regulations, safety standards, guidelines and generally recognized technical regulations (e.g. DIN standards, VDE directives, technical regulations of other European Union member countries or other contracting states of the agreement on the European economic area) to such an extent that he can judge the safe working condition of fume hoods."

The regular test comprises:
  1. The general visual inspection of the safe working condition of the fume hood (with fume hoods acc. to DIN 12 924 Part 1 of August 1991 with self-monitoringtechnical facilities for permanent monitoring, which signalize monitoring unavailability by reporting the fault optically and acoustically in the event of contamination, corrosion, chemical pollution, ageing or electrical faults - with fume hoods acc. to DIN 12 924 Part 1 with technical facilities for permanent monitoring - function display with fume hood acc. to DIN 12 924 of January 1978) with regard to:

    • Sound condition of the fume hood setup
    • Deposits on the rear wall
    • Proper operation of the front sliding valve
    • Sound condition of the glazing
    • Correct ventilation connection
    • Additional (lockable?) openings
    • Thermal pollution in the fume hood
    • Sound condition of the sill plate incl. disposition


  2. The mechanical control of the front sliding valve mechanism (with fume hoods acc. to DIN 12 924 Part 1 of August 1991 with self-monitoring technical facilities for permanent monitoring, which signalize monitoring unavailability by reporting the fault optically and acoustically in the event of contamination, corrosion, chemical pollution, ageing or electrical faults - with fume hoods acc. to DIN 12 924 Part 1 with technical facilities for permanent monitoring - function display with fume hood acc. to DIN 12 924 of January 1978) with regard to:

    • Smooth running
    • Toe-in or toe-out
    • Noises
    • Damage to ropes or weights


  3. The ventilation operation test based on the manufacturer's information: the following determinations apply alternatively for fume hoods that were put into operation before October 1, 1993:

      • Table/platform fume hoods (working surface height 900 mm) need 400 m3 air-volume current per running meter frontage
      • Deep vents (working surface height 500 mm) need 600 m3 air-volume current per running meter frontage
      • Passable vents (working surface height 0 mm) need 700 m3 air-volume current per running meter frontage
      • Treatment fume hoods (working surface height 900 mm) need 700 m3 air-volume current per running meter frontage

    1. The regular testing of the ventilating function can take place as differential pressure or speed measurement in ventilating nozzles above the hood or at the front sliding valve opening. (With fume hoods according to DIN 12 924 Part 1 with technical facilities for permanent monitoring function display - with fume hoods acc. to DIN 12 924 of January 1978)
    2. The speed measurement can take place by determination of the average admission speed with a front valve opened at a height of 100 mm. Suitable measurement devices are for example thermal or hydrometric vanes. (With hoods acc. to DIN 12 924 of January 1978).


  4. The examination of the technical facilities for permanent monitoring (with fume hoods acc. to DIN 12 924 Part 1 of August 1991) with self-monitoring technical facilities for permanent monitoring according to the manufacturer's specification - with fume hoods acc. to DIN 12 924 Part 1 with technical facilities for permanent monitoring - function display annually).