Workshop Waste Management Checklist

Pre-Workshop Setup

Waste Collection Infrastructure

☐ Silver-bearing waste container

  • Labelled: “SPENT FIXER / BLIX – CONTAINS SILVER – HAZARDOUS”
  • Capacity: At least 2× expected fixer volume
  • Lid that seals

☐ General hazardous waste container

  • Labelled: “HAZARDOUS DARKROOM WASTE – DO NOT DRAIN”
  • For: colour chemistry, toners, specialty chemicals
  • Separate from silver waste if possible

☐ Neutralisation station (if using acids/bases)

  • Sodium bicarbonate (for neutralising acids)
  • Weak acid/vinegar (for neutralising bases)
  • pH strips
  • Mixing container

☐ Rinse water collection (optional but good practice)

  • First rinse water contains most residual chemistry
  • Can be collected and treated as hazardous if volume permits

Process-Specific Setup

For standard B&W: ☐ Two-bath fixer system ready ☐ Silver test supplies available

For C-41/RA-4 colour: ☐ All chemistry containers labelled ☐ Blix/bleach-fix collection separate from B&W fixer ☐ Gloves available (CD-3/CD-4 are sensitisers)

For mordançage: ☐ Copper chloride bleach in dedicated, labelled container ☐ Sodium hydroxide available for neutralisation ☐ Participants informed: bleach is reusable—do not discard

For chromoskedasic sabattier: ☐ Brush application setup (NOT tray method) ☐ Small containers for working solutions (50–100ml max) ☐ Thiocyanate waste container labelled ☐ Ventilation confirmed adequate ☐ Vapour masks available

For toning (selenium): ☐ Selenium toner in dedicated container ☐ Participants informed: replenish, do not discard ☐ Hazardous waste collection arranged for eventual disposal

For gum bichromate: ☐ STOP — Confirm participants understand dichromate is carcinogenic ☐ Gloves mandatory ☐ All dichromate waste collected — nothing down drain ☐ Separate labelled container: “DICHROMATE – CARCINOGENIC – HAZARDOUS”

Participant Briefing Checklist

Before workshop begins, ensure all participants understand:

☐ The hierarchy: Silver is the primary concern (~80% of impact)

☐ What's drain-safe:

  • Wash water (after initial rinse)
  • Oxidised B&W developer (diluted)
  • Neutralised stop bath

☐ What's NEVER drain-safe:

  • Fixer (contains silver)
  • Bleach-fix / blix (contains silver)
  • Colour chemistry (developer, bleach)
  • Toners (especially selenium)
  • Mordançage bleach (copper)
  • Chromo chemistry (thiocyanate)
  • Dichromate (gum bichromate)

☐ Container locations: Point out all waste containers

☐ Spill procedure: What to do if chemistry spills

☐ PPE requirements: Gloves for colour/specialty processes

During Workshop

Ongoing Monitoring

☐ Waste containers not overflowing ☐ Correct chemistry going to correct containers ☐ No one pouring fixer down the drain ☐ Ventilation adequate (especially for chromo, sulfide toning) ☐ Spills cleaned up promptly

Common Problems to Watch For

Problem Solution
Participant about to pour fixer down drain Intervene immediately; redirect to collection
Mixed waste in wrong container Note it; may complicate disposal but don't panic
Chromo tray method being used Stop; switch to brush application
Mordançage bleach being discarded Recover if possible; it's reusable
Selenium toner being discarded Recover; it lasts years with replenishment
Strong chemical smell Check ventilation; take break if needed

Process-Specific Monitoring

Lith printing:

  • Standard B&W waste profile
  • Developer is very dilute—less concern than standard
  • Fixer is the issue, as always

Mordançage:

  • Ensure bleach returns to storage container after use
  • Collect silver chloride precipitate if bleach is being strained
  • Remind participants: one batch lasts 100+ prints

Chromoskedasic:

  • Enforce brush method only
  • Monitor solution volumes—should be using 40–60ml total, not litres
  • Collect ALL waste, even small amounts

End of Workshop

Chemistry Handling

☐ Fixer

  • Pour into silver-bearing waste container
  • Do NOT mix with colour blix (different recovery chemistry)
  • Record approximate volume

☐ Colour developer

  • Collect in hazardous waste container
  • Or return to storage if reusable

☐ Colour bleach/blix

  • Collect in dedicated container (silver-bearing)
  • Label if mixed with B&W fixer

☐ Stop bath

  • If acetic acid: neutralise with bicarb, then drain
  • If water: drain directly

☐ B&W developer

  • If still usable: return to storage
  • If exhausted: can drain with dilution (low hazard)

☐ Mordançage bleach

  • Return to storage container for reuse
  • Top up with hydrogen peroxide if weakened
  • Do NOT discard

☐ Chromo solutions

  • Collect ALL waste in hazardous container
  • Even small brush-wash volumes

☐ Toners

  • Selenium: return to storage; replenish if needed
  • Sulfide: can drain with dilution after neutralising
  • Gold: collect for hazardous waste

Equipment Cleaning

☐ Trays rinsed (rinse water to appropriate container for first rinse) ☐ Tongs/tools rinsed ☐ Work surfaces wiped down ☐ Brushes cleaned (chromo brushes kept separate)

Waste Container Management

☐ All containers sealed ☐ All containers labelled with:

  • Contents
  • Date
  • Approximate volume
  • “HAZARDOUS” where applicable ☐ Containers stored securely (not accessible to unauthorised persons) ☐ Disposal arranged (see below)

Post-Workshop Disposal

Immediate (within 1 week)

☐ Silver-bearing waste: Begin steel wool treatment OR store for professional collection ☐ Neutralisable waste: Neutralise and drain ☐ Reusable chemistry: Properly stored for next session

Scheduled (arrange in advance)

☐ Hazardous waste collection date: __________ ☐ Contact: __________ ☐ Materials to dispose:

  • ☐ Exhausted fixer (after silver recovery)
  • ☐ Colour chemistry
  • ☐ Selenium toner (when truly exhausted)
  • ☐ Mordançage bleach (when truly exhausted)
  • ☐ Chromo waste
  • ☐ Dichromate waste (if applicable)
  • ☐ Silver sludge from recovery

Documentation

☐ Volume of each waste type recorded ☐ Disposal receipts retained (if professional collection) ☐ Any incidents noted

Quick Reference: Workshop Waste by Process

Process Primary Waste Disposal Method
B&W film/print Fixer (silver) Steel wool recovery → drain
C-41 Developer, blix (silver) Hazardous waste collection
RA-4 Developer, blix (silver) Hazardous waste collection
Lith Fixer (silver) Steel wool recovery → drain
Mordançage Copper bleach Reuse; eventual haz waste
Chromo Thiocyanate, KOH Hazardous waste collection
Selenium tone Selenium compounds Reuse; eventual haz waste
Sulfide tone Sulfide solution Neutralise → drain
Cyanotype Iron rinse water Drain (safe)
Gum bichromate Dichromate Hazardous waste—carcinogen

Emergency Procedures

Chemical Spill

  1. Small spill (<100ml): Absorb with paper towels, dispose as hazardous waste
  2. Large spill: Contain spread, ventilate area, absorb, dispose as hazardous
  3. Dichromate spill: Treat as serious; full cleanup, all materials to hazardous waste

Skin Contact

  1. Most darkroom chemicals: Rinse thoroughly with water for 10+ minutes
  2. Strong acids/bases: Rinse 15+ minutes; seek medical attention if burns visible
  3. Dichromate: Rinse thoroughly; note exposure for medical records
  4. Silver nitrate: Rinse; staining is harmless but persistent

Eye Contact

  1. Rinse with eyewash or clean water for 15+ minutes
  2. Seek medical attention for any chemical eye exposure
  3. Bring SDS sheet to medical provider if available

Ingestion

  1. Do not induce vomiting
  2. Rinse mouth with water
  3. Seek medical attention
  4. Bring container/SDS to medical provider

Workshop Leader Sign-Off

Pre-workshop setup complete: ☐ Yes

Participant briefing delivered: ☐ Yes

End-of-workshop procedures complete: ☐ Yes

Waste disposal arranged: ☐ Yes

Signature: __________________ Date: __________

Sustainable Darkroom series