Presentation on theme: "Chromates (Hexavalent Chromium) ASSE ASSE Region III Professional Development Conference Austin, Texas August 7, 2006 Frank M Parker, III CIH, CSP, PE,"— Presentation transcript:
Chromates (Hexavalent Chromium) ASSE ASSE Region III Professional Development Conference Austin, Texas August 7, 2006 Frank M Parker, III CIH, CSP, PE, DEE
Chromates Chrome Compounds –Chrome (II) CrF 2 Green CrCl 2 White CrBr 2 White CrI 2 Red-Brown –Chrome (III) CrF 3 Green CrCl 3 Red-Violet CrBr 3 Green-Black CrI 3 Black Cr 2 O 3 Green
Chromates Chrome Compounds –Chrome (IV) CrO 2 Brown - Black –Chrome (VI) CrO 3 Deep RedK 2 Cr 2 O 7 CaCrO 4 YellowNa 2 Cr 2 O7·2H 2 O PbCrO 4 YellowSrCrO 4 K 2 CrO 4 ZnCrO 4
Chromates Health Effects –Cr (III) 50 – 200 µg / day Required in Diet Irritation, Dermatitis, Allergies –Cr (VI) Water Soluble –Liver, Kidney, Respiratory Insoluble –Cancer, Irritation
Chromates Where Chromates (VI) Are Found –Pigments (paints, inks, & plastics) –Spray Coatings –Stainless Steel –Electroplating & Metal Cleaning –Corrosion Inhibitors –Wood Preservatives –Tanning –Textiles Dyes –Chromate Production
Chromates OSHA’s Final Rule Published: February 28, 2006 Effective Date: + 90 days Start up Date: 180 days (1 year for Employers < 20 Workers) Engineering Controls: 4 years
Chromates Permissible Exposure Limits Chromium (VI) in any form or compound AL = 2.5 µg/m 3 (8 hr. TWA) PEL = 5 µg/m 3 (8 hr. TWA) Aircraft Industry: 25 µg/m 3 + RPE Portland Cement & Pesticides: NA
Chromates IH Sampling –8hour TWA: Sufficient Number of Samples Each Employee Full Shift Each Shift Each Job Class Each Work Area Accuracy For Concentrations ≥ A.L. –Monitoring & Analysis Accuracy = ±25% –Accurate Measurements = 95% C.L.
Chromates Scientific Challenges –Sampling; Enough volume for LOD –Analysis Quantifying Concentrations of Metals (Sr, Pb, Ca, etc) Quantifying Cr +6 –Calculating Exposure Concentrations
Chromates Calculations –Consume Cr +6 per Hierarchical Method Sr – 0.005 µg/m 3 First; Ca – 0.001 µg/m 3 Next; tBCr – 0.001 µg/m 3 Next; Pb – 0.012 µg/m 3 Last.
Chromates Program Challenges –Finding Chromates in the workplace; –Selling the effort necessary to quantify exposures; –Maintaining program for all future use of chromates; –Dealing with PR issues surrounding historical exposures; –Meeting the statistical standards; –Finding substitutes; –Implementing appropriate controls; –Keeping your program between OSHA, ACGIH, NIOSH, etc. and the current state of art and science.
Chromates Mother Nature Doesn’t Give a Dam! People don’t do what you expect them to do, they do what you inspect them to do. Good safety programs are not free. A significant percentage of your workers will get cancer! Cancer is not free; someone will pay the bill. The only question is who? Time is of the essence.