Community Darkroom Guidelines

Sustainable Practice for Shared Spaces

THE GOLDEN RULE

Never pour fixer down the drain.

Your fixer contains 3,000–8,000 mg/L dissolved silver. Aquatic life dies at 0.6 ΞΌg/L.

This is non-negotiable. No exceptions. Ever.

Waste Stations

πŸ”΄ SILVER-BEARING WASTE

Location: _________________

Put here:

  • ALL spent B&W fixer
  • ALL spent colour blix/bleach-fix
  • First rinse water after fixing (optional)

Never:

  • Pour down any drain
  • Mix with other chemicals
  • Leave unlabelled

🟑 HAZARDOUS CHEMISTRY

Location: _________________

Put here:

  • Colour developer (C-41, RA-4)
  • Colour bleach
  • Selenium toner (when exhausted)
  • MordanΓ§age bleach (when exhausted)
  • Chromo solutions
  • Any unknown chemistry

🟒 DRAIN-SAFE

Location: Sink

OK to drain (with water):

  • Wash water
  • Oxidised B&W developer (brown/black)
  • Neutralised stop bath
  • Cyanotype rinse water

Two-Bath Fixing System

This darkroom uses two-bath fixing to extend fixer life 4–10Γ—.

β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”      β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”
β”‚   FIRST BATH    β”‚  β†’   β”‚  SECOND BATH    β”‚
β”‚    (older)      β”‚      β”‚   (fresher)     β”‚
β”‚                 β”‚      β”‚                 β”‚
β”‚  Brief fix      β”‚      β”‚  Full fix time  β”‚
β”‚  30-60 sec      β”‚      β”‚  2-4 min        β”‚
β””β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜      β””β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜
     ↓ When exhausted:
     1. Silver recovery
     2. Discard first
     3. Promote second β†’ first
     4. Make fresh second

Your responsibility:

  • Use BOTH baths in sequence
  • Log your usage
  • Report if first bath tests exhausted

Silver Recovery

Method: ☐ Steel wool ☐ Electrolytic ☐ Professional collection

Status indicator:

Light Meaning Action
🟒 System working Proceed normally
🟑 Needs attention Check with manager
πŸ”΄ Full/offline DO NOT add fixerβ€”notify staff

Current status: ____________

Water Efficiency

Film Washing (Ilford Method)

Step Inversions Drain completely
1 5 βœ“
2 10 βœ“
3 20 βœ“

Total: ~2 litres per roll

❌ Do not run water continuously for 20+ minutes

RC Paper: 2 minutes maximum. Do not overwash.

Fibre Paper: Use HCA bath, then sequential tray washes.

HCA location: _________________

❌ Do not run water continuously for 60 minutes

Chemistry Handling

Before You Start

☐ Check fixer test logβ€”is fixer still good? ☐ Check silver recovery status ☐ Know where waste containers are ☐ Have appropriate PPE for your process

During Processing

☐ Use chemistry efficiently (don't overfill trays) ☐ Return reusable chemistry to storage containers ☐ Wipe up spills immediately ☐ Keep work area clean

When You Finish

☐ Fixer β†’ silver-bearing waste container ☐ Developer β†’ drain (if oxidised) or storage (if reusable) ☐ Stop bath β†’ neutralise and drain, or storage ☐ Rinse trays (first rinse to appropriate container) ☐ Log your session ☐ Leave space clean for next user

Process-Specific Rules

Standard B&W

  • Two-bath fixer system
  • Log rolls/prints processed
  • Silver recovery from all fixer

Colour (C-41/RA-4)

  • Gloves required (CD-3/CD-4 are sensitisers)
  • ALL chemistry to hazardous waste
  • Temperature controlβ€”don't waste chemistry on failed batches

Lith Printing

  • Standard B&W waste profile
  • Developer is very diluteβ€”drain-safe when exhausted
  • Fixer rules apply as normal

Toning

  • Selenium: Return to storage; never discard; lasts years
  • Sepia/sulfide: Ventilate; drain-safe when done
  • Other: Check with staff

Mordançage

  • Bleach is REUSABLEβ€”return to storage container
  • Location: _________________
  • Notify staff when bleach weakens (slower action)
  • Never discard without authorisation

Chromoskedasic Sabattier

  • Brush application ONLYβ€”no tray method
  • Collect ALL waste, even small amounts
  • Ventilation required
  • Waste container location: _________________

Alternative Processes (Cyanotype, etc.)

  • Cyanotype: drain-safe
  • Van Dyke/Kallitype: silver recovery applies
  • Gum bichromate: DICHROMATE IS CARCINOGENICβ€”special handling required

Logging Requirements

Session Log

Location: _________________

Record:

  • Date
  • Your name
  • Process used
  • Rolls/prints processed
  • Fixer bath used
  • Any issues

Fixer Test Log

Location: _________________

Test before each session or every 10 rolls.

Record:

  • Date
  • Tester name
  • Bath tested
  • Result
  • Action taken

Safety

PPE Available

Location: _________________

  • Gloves (nitrile)
  • Safety glasses
  • Apron
  • Vapour mask (for chromo, sulfide toning)

First Aid

Location: _________________

Emergency Procedures

Chemical spill:

  1. Contain spread
  2. Absorb with paper towels
  3. Dispose as hazardous waste
  4. Notify staff

Skin contact:

  1. Rinse with water 10+ minutes
  2. Report to staff
  3. Seek medical attention if irritation persists

Eye contact:

  1. Eyewash station: _________________
  2. Rinse 15 minutes
  3. Seek medical attention

The Hierarchy of Impact

Priority Issue Contribution
1 Silver in fixer ~80%
2 Water consumption ~10%
3 Hazardous chemistry ~5%
4 Developer choice ~2%

Address the big things first.

Silver recovery is not optional in this space.

Questions?

Darkroom manager: _________________

Contact: _________________

Hours: _________________

Community Agreement

By using this darkroom, I agree to:

☐ Never pour fixer or silver-bearing waste down any drain

☐ Use the two-bath fixing system correctly

☐ Log my sessions and fixer tests

☐ Dispose of all waste in designated containers

☐ Leave the space clean for the next user

☐ Report any problems or supply issues to staff

Signature: _________________ Date: _________

Sustainable Darkroom series