Recently OSHA completed an inspection at a workplace where they identified a hazard that was not a violation of a specific OSHA standard, nor was it considered appropriate at the time to invoke Section 5(a)(1) of the Occupational Safety and Health Act (e.g. General Duty Clause). In these cases, OSHA may send the employer a formal letter asking/suggesting the employer address said hazard(s). This was done most recently this month and was related to storage of peracetic acid (PAA). During the course of the inspection, the CSHO discussed conditions and/or practices related to peracetic acid use. OSHA then followed up with a letter – the letter goes on to state…
In particular, a 250 gallon-sized chemical tote containing PAA, an organic acid and strong oxidizer, was stored on the floor next to other chemical totes (of the same size) containing an incompatible strong base, sodium hydroxide (NaOH).
No secondary containment was provided, exposing employees to the hazards associated with an adverse chemical reaction between these two incompatible chemicals. The filling and emptying process for these totes is visual only, contributing to a possibility of spillage, where the incompatible chemicals could mix. Decomposition of PAA can be prompted by erroneous contamination with a base such as NaOH. Reactions between strong acid and strong bases produce heat and can be violent. The production of heat during this reaction could increase the decomposition rate of PAA under certain conditions, leading to an uncontrolled reaction.
Pursuant to Section 21 of the Act, which authorizes OSHA to train employers and employees about workplace hazards and appropriate abatement methods, it is recommended that the following steps be taken as a means of reducing the risk of injury to employees working in your facility:
- Segregate PAA and NaOH totes;
- Install secondary protection measures, such as dedicated, isolated storage areas with containment curbs for PAA and NaOH totes;
- Modify the filling and emptying process for the PAA and NaOH totes to include indicators of chemical level that do not rely on visual determination, such as floats/float switches.
Fortunately, no employee injury was reported to be associated with this hazard. However, these safety enhancements are recommended in order to avert potential future accidents. While no OSHA standards appear to address these conditions as noted during the inspection, nor is it considered appropriate at this time to invoke Section 5(a)(1) of the Occupational Safety and Health Act, it should be noted that specific OSHA standards or Section 5(aX1) maybe applicable in the future.
You can find information about safety and health programs, plus an array of electronic e-tools, publications and other information at www.osha.gov. Your interest in and support of the occupational safety and health of your employees is greatly appreciated. If you have any questions regarding these recommendations, please do not hesitate to contact this office.
Sincerely,
Erin G. Patterson
Area Director
US Department of Labor
CLICK HERE to see the letter