http://www.safety.ed.ac.uk/resources/index.shtm
  
UK Health and safety site. Safety information on fire, radiation and biological hazards. Good links to other sources of information.
  
http://europe.osha.eu.int/
  
European Agency for Health and Safety at Work. Has an excellent A-Z index covering all the major hazard groups. Includes downloadable fact sheets.
  
http://www.hsa.ie/safety/index.htm
  
The Irish Health and Safety Authority. Includes general information on health and safety in the workplace with links to relevant publications (available for purchase).
  
http://www.epa.ie/
  
The Environmental Protection Agency (Ireland). Includes a web page on GMO regulations and licensing. Also includes a page on regulations pertaining to the use of solvents.
  
http://www.who.int/health_topics/en/
  
World Health Organisation – Health Topics. A comprehensive A-Z index covering both work-related and general health hazards.

http://www.cdc.gov/niosh/database.html
  
National Institute for Occupational Safety and Health (USA; a subsidiary site of the Centre for Disease Control). Access to a number of comprehensive chemical databases. Links to chemical data sheets and other general safety information.
  
http://www.hc-sc.gc.ca/pphb-dgspsp/ols-bsl/index.html
  
Office of Laboratory security – Canadian Health Authority. Contains comprehensive information on biohazards including pathogen classification.  

http://www.ehs.cornell.edu/
  
Environmental Health and Safety (hosted by Cornell University, USA). A very useful site with searchable databases. It has detailed information on most aspects of safety in the workplace, including fire, chemical, radiation, biological and occupational safety.
  
http://www.msdssearch.com/DBLinksN.htm
  
Material Safety Data Sheet (MSDS) databases. An excellent site with links to several very extensive databases. For specific in formation a particular chemical this is probably the best site to start at (no registration required).