Engineering and Technical Support Group
School of Information Technology & Electrical Engineering

OH&S Requirements

  1. Ensure you have either completed a Risk Assessment or read (and confirmed as being read) the relevant Risk Assessment before attempting to operate this equipment
  2. The Process ID which refers to the general Risk Assessment regarding activities in the Darkroom / PCB Etching Facility is 19251 and addresses the chemicals used in conjunction with this equipment
  3. The UQ Risk Management Database is located at: https://www.risk.admin.uq.edu.au/Signin.aspx
  4. Ensure the fume extraction system is switched on and running
  5. Visually check the equipment is safe to operate and the electrical safety tag is current.  If expired, the equipment must be tested and tagged before proceeding
  6. Wear safety glasses, gloves and a lab coat before operating this equipment or attempting to add chemicals to the tanks
  7. Clean room protocols apply to the Darkroom / PCB Etching Facility

Tank Levels & Chemical Replacement

  1. Check for adequate levels in the 3 tanks and ensure their contents have not exceeded their use by dates.  This can be confirmed by checking the associated log sheet.
  2. If required, top up or replace as required ensuring the maximum level (as indicated on each drain hose) is not exceeded
    1. Ensure the heater controller has been turned off and unplugged from the power source for at least one hour and the contents of each tank is below 35oC before continuing
      • Tank A 9L Max Developer EEL 50-11-04 Use 1 part chemical to 2 parts tap water
      • Tank B 9L Max Rinse Tank EEL N/A Tap water
      • Tank C 9L Max Fixer EEL 50-11-05 User 1 part chemical to 2 parts tap water
    2. Tank A should be drained, thoroughly washed with water and the developer replaced at periods no greater than 12 months.  The associated log sheet should be updated at each event.
    3. Tank B should be drained, thoroughly washed and the water replaced at periods no greater than 4 weeks.  The associated log sheet should be updated at each event
    4. Tank C should be drained, thoroughly washed with water and the fixer replaced at periods no greater than 12 months.  The associated log sheet should be updated at each event
  3. To empty each tank, carefully remove the flexible hose from it's holder and close the opening by placing your thumb over the end of the hose
    • Place the end of the hose into a suitable receptacle, remove your thumb and drain the tank
    • Remember to replace the hose in it's holder before refilling the tank
    • Chemicals are to be disposed of in accordance with University policy
  4. Chemicals are to be disposed of in accordance with University policy

Operating Temperature

  1. Set the heater switch to on and allow chemicals to reach a nominal temperature of 30oC before continuing
    • A small heater is situated in Tank B which is designed to maintain the temperature of the water and adjoining tanks to approx 28oC - 34oC

Developing and Fixing Process

  1. Ensure the door to the darkroom is shut and the safelights are adjusted to the required level before removing the film from the photoplotter (to be better defined at a later date)
    • Before continuing, be aware that cross contamination between Tank A and Tank C will render the chemicals unusable
  2. Remove the tank covers and place in a secure location
  3. Stir contents of Tank A and Tank C, using exclusive tools for each tank
  4. Immerse the film in the Developer Tank A for 1 minute
  5. Rinse well in water Tank B
  6. Immerse the film in the fixer Tank C for 1 minute
  7. Rinse well in water Tank B
  8. Carefully pat both sides of the film dry using a paper towel
  9. Hang to dry for approx 15 minutes and ensure the developed film is no longer opaque
    • The film should be sufficiently dry such that liquid does not drip on the floor

Shutdown Instructions / End of Day

  1. Set the heater switch to off
  2. Ensure the fume extraction system is turned off, unless in use by another operator
  3. The equipment is to be thoroughly cleaned and chemicals spills removed
  4. Before leaving, please ensure the room is left in a clean and orderly fashion
  5. Leave the door wide open in order to eliminate the possibility of a build up of chemical odours

Additional Information

  1. The manufacturers safety data sheet for the Developer EEl 50-11-04 is MSDS003
  2. The manufacturers safety data sheet for the Fixer EEL 50-11-05 is MSDS 004

Amendments to Procedure

Inform the Engineering & Technical Support Manager at the earliest opportunity if this procedure has, or needs to be altered in any way.