NIH Dark Room Operations
Wet photo-processing rooms (aka dark rooms) utilize special paper containing light-sensitive silver compounds to create a high-quality photograph. The solutions used during the development process release the unexposed silver compounds, creating a source of hazardous waste. As a result, it is crucial that all dark rooms on NIH campuses adhere to all Federal, State and local regulations for wastewater discharge. On the Bethesda campus, these regulations are enforced by the Environmental Protection Agency (EPA) and the Washington Suburban Sanitary Commission (WSSC). Dark rooms are subject to inspection by these groups, in addition to wastewater monitoring. Violations found from these compliance checks can result in fines and the suspension or revocation of discharge privileges.
In accordance with WSSC regulations, the NIH has determined that all dark rooms must have:
1) A silver recovery unit (SRU) or effluent precipitation and neutralization (EPAN) chamber.
2) Secondary containment placed under the SRU or EPAN chamber.
3) A maintenance record kept within the dark room area (a sticker with the most recent service date, at minimum).
4) A designated point of contact (POC), with their contact and IC information clearly posted outside the dark room.
In accordance with the NIH Waste Disposal Guide, all waste from wet photo-processing rooms must be collected and disposed as chemical waste. The fixer and developer solutions must be collected separately in their own individual chemical waste carboys (Do not mix fixer and developer waste!). The waste lines from an SRU should NEVER connect to a sink or drain. Consult the NIH Waste Disposal Guide for guidance on collecting and disposing chemical waste.
Any questions regarding the requirements for dark room operations should be directed to the Office of Research Facilities, Division of Environmental Protection at 301-496-7775.