Advanced Environmental Group, Inc. - CA Aero Environmental Services - CA AGX, Inc. - PA AirQuest Environmental, Inc. - CA, FL Alliance Consulting International - CA ALTIH LLC - NJ AM Health and Safety, Inc. - PA American Analytical Laboratories, Inc. - OH Analytical Consulting Group, Inc. - CA Applied Improvement Technologies, LLC - CT Associated Wyoming Environmental Testing - WY Associates in Occupational + Environmental Health, LLC - CO Atlas - AK, AL, AZ, CA, CO, CT, FL, GA, HI, IA, IL, IN, KS, KY, LA, MA, MD, MI, MN, MO, NC, NE, NH, NJ, NV, NY, OH, OR, PA, RI, SC, TN, TX, UT, VA, VT, WA Atlas Technical Consultants - ID Aurora Industrial Hygiene - CA Aurora Industrial Hygiene - CA Baer Engineering and Environmental Consulting, Inc. - TX BDN Industrial Hygiene Consultants, Inc. - MI Benchmark Safety, Health & Environmental Services - WV BluMetric Environmental Inc. - ON CanAm Environmental Safety, Inc. - NY Carnow, Conibear & Associates, Ltd. - IL Cashins & Associates, Inc - MA Central Colorado Industrial Hygiene, LLC - CO Century Environmental Hygiene, LLC - CO Chemistry & Industrial Hygiene, Inc. -CO CIH Service, LLC - TN Citadel EHS, Inc. - CA Clean Environments, Inc. - TX Coastal Safety, LLC - CT Colden Corporation - LA, NH, NY, PA Compliance Management International - PA Control EHS - GA CRAWSA Environment and Health, LLC - AL DirectCIH, LLC - AL DNA Industrial Hygiene - CA Dotson Group, LLC - AZ Eagle Industrial Hygiene Associates, Inc. - PA ECOH Management, Inc. - ON EI Group, Inc. - GA, KY, NC, SC, VA Elysium Environmental Services, Ltd. - SC Emerald Environmental, Inc. - OH Empire Environmental, Ltd. - NJ

EMS Safety Solutions - CA EnHealth LLC - MN Environmental Health Investigations, Inc. (EHI Inc.) - NJ Environmental Health Management - KY Environmental Safety Consultants, Inc. - FL Environmental Safety Management Corporation - NJ EnvirOSH Services, Inc. - TX EPIC - AZ, GA, IL, TX Euro Safety & Health - UK Forensic Analytical Consulting Services, Inc. (FACS) - CA, IL, MI, NV, OR G.E. Risk Management, LLC - FL Gallagher Bassett Technical Services - FL, IL Garden State Environmental, Inc. - NJ Harris & Lee Environmental Sciences, LLC - CA Health and Safety Services, LLC - ID Health Science Associates - CA Helix Environmental, Inc. - OH Hellman & Associates, Inc. - CO High Environmental Health & Safety Consulting Ltd. - PA HRA Environmental Consultants, Inc. - CA Hutzel & Associates, Inc. - AZ IES Engineers - PA IHSC, LLC - CT Incident Free Operations - TX Indoor Environmental Concepts, LLC - NJ Indoor Science - IL Industrial Hygiene Resources, Ltd. - ID Insight Exposure & Risk Sciences Group - CO Insight IH Consulting, LLC - WI J.E. Spear Consulting, LP - TX James R. Strobridge, CIH, LLC - MI Jan Koehn, M.S., CIH, Inc. - TX Jeff Pothast & Associates, Inc. - CO Jobspot Health and Safety Solutions - OR John A. Jurgiel & Associates, Inc. - MO, TX Kaizen Safety Solutions, LLC - AZ Liberty Occupational Health Management, Inc. - OK M.B. Amster & Associates, Inc. - MA Mabbett & Associates, Inc. - MA, VA Marshall Environmental Management, Inc. - OK Microecologies, Inc. - NY MML Environmental, Inc. - CA Morris Industrial Hygiene and Safety - MD Mystic Air Quality Consultants, Inc. - CT Ninyo & Moore Geotechnical & Environmental Consultants - CA NORTECH, Inc. - AK Occuhealth, Inc. - MA Occupational Environmental Health Solutions, Inc. (OEHS) - IL OHE Consultants - ON Omega Environmental Services, Inc. - NJ Pacific EH&S Services, Inc. - CA Page Engineering, Inc. - MI Pennoni - PA PHASE Associates, LLC - NJ Pinchin Ltd - ON Pinyon Environmental, Inc. - CO Precision Environmental Inc. - NC, NY PSARA Technologies, Inc. - OH QUEST Environmental - CO R&R Environmental, Inc. - UT Ramboll - CA, CO, FL, IL, IN, LA, MI, MN, MO, NJ, OH, ON, OR, WA, WI RHP Risk Management, Inc. - IL, PA, TN RISC, LLC - VA SafeBridge Regulatory & Life Sciences Group - CA, NY Safety Priority Consultants, LLC - CT SafeX, Inc. - OH Sandler Occupational Medicine Associates, Inc. (SOMA) - VA Sentinel Safety Group, LLC - IN SHEPRD, LLC - SC Skelly and Loy, Inc., A Terracon Company - PA Skyline Environmental, Inc. - NJ Southern Environmental Management & Specialties, Inc. (SEMS) - MS Stonehouse Process Safety, Inc. - NJ T. Harris Environmental Management, Inc. - ON TEM Environmental, Inc -IL Terracon Consultants, Inc. - AL, AZ, CA, CO, FL, GA, IA, KS, LA, MN, MO, MS, NC, NE, OH, OK, SC, TX, UT, WA Testing Engineers and Consultants, Inc. - MI Tetra Tech, Inc. - CA, TX, WA The Environmental Quality Organization, LLC - CA Theodore J. Hogan & Associates, Inc. - IL Tormod LLC - AL W.L. Bouchard & Associates, Inc. - AZ Watson & Associates Occupational Hygiene and Safety, LLC - NY Weaver Consultants Group - IL, TX Work Environment Associates, Inc. - VA Workplace Safety & Health Company, Inc. - IN