link to homepage

Navigation and service

Chemical Hazards

A variety of chemical hazards exist in the HNF. HNF users are expected to educate themselves about chemicals, take the necessary precautions associated with chemicals, and conduct themselves in a safe manner when handling chemicals.

Hydrofluoric Acid (HF)

HF burns are extremely serious and result in massive tissue damage. HF burns may not cause discomfort until long after exposure.
If a user contacts HF, or suspects they have contacted HF, flush the area well with water for 5 minutes. Immediately contact the medical service for examination.
Buffered HF (AF91-09) is NOT dilute HF. The fluorine content is the same as in HF no matter what the ratio of buffered HF is. Therefore the same action has to be taken as for HF.


Instructions for safe use of piranha solutions:

  • Substrates should be triple rinsed and dried before placed in a piranha solution
  • Do not store wash bottles near piranha (IPA and acetone)
  • No Photoresist stripping near any piranha
  • No acid piranha in dropped decks

Cryogenic (Liquid Nitrogen (LN2))

Cryogenic hazards exist in the HNF. HNF users should familiarize themselves with cryogenic materials to avoid injury.
LN2 s used throughout the lab. LN2 has a sufficiently low temperature, -196°C (77°K), to burn skin from freezing and to crack the flooring. HNF users should take all necessary precautions when working with or around LN2.

  • Only authorized personnel may fill LN2 containers.
  • Only containers designed for transporting LN2 are allowed.
  • Special gloves must be worn when handling LN2

Handling gases

·         The TRGS (Technische Regeln für Gefahrstoffe) are applicable.

·         Gas cylinders are normally to be placed in extracted safety cabinets.

·         Gas cylinders with toxic, corrosive or highly flammable gases should be chosen as small as possible. These cylinders are to be placed and secured in the gas cabinets of HNF.

·         Cylinders must be moved with special trolleys and with a valve cap mounted to the top. Carrying the bottles is strictly prohibited.

·         For taking gas from compressed gas cylinders only fittings and hoses that are allowed for each respective type of gas and pressure may be used. Particular care must be taken that oxygen does not come into contact with oil or fat.

·         Compressed gas cylinders, whose valves cannot be opened by hand, must be marked and taken out of order.


Because of the potential exposure to chemicals, working in the HNF while pregnant is at the users own risk. Chemicals that cause miscarriages and birth defects may only be used with HNF permission and proper training.