Protecting Workers from Hexavalent Chromium Surface Accumulations
Hexavalent chromium, a.k.a Cr (VI), is a hazardous compound found in a variety of industrial processes. Hexavalent chromium is used in, but not limited to, pigments, metal finishing, wood preservatives, dyes and coatings, fungicides, and chemical synthesis processes. Hexavalent chromium may also be present in fumes generated during the production or welding of chrome alloys.
Workers may be exposed to Hexavalent chromium through inhalation (dust, mist or fumes), or dermal or eye contact with dust or liquids. Additionally, workers may be exposed to Hexavalent chromium through ingestion, via handling food, cigarettes, and applying cosmetics with hands contaminated with hexavalent chromium. Workplace exposure to airborne chromium (VI) may cause the following health effects: lung cancer; irritation or damage to the nose, throat and lungs; irritation or damage to the eyes and skin. Ingestion may cause severe abdominal pain, vomiting and hemorrhaging. Therefore, housekeeping has an impact on the magnitude of workplace exposure. For this reason, the Hexavalent chromium Cr (VI) standard for general industry includes requirements for housekeeping.
In the Hexavalent chromium standard, 29 CFR 1910.1026(j)(1)(i) states the employer shall ensure all surfaces are maintained as free as practicable of accumulations of Hexavalent chromium. Proper housekeeping requirements are important because they target possible sources of exposure to Hexavalent chromium. Exposed employees can inhale or ingest Hexavalent chromium while performing tasks using the compound or being exposed to in the compound in the workplace.
In order to ensure employee protection against Hexavalent chromium exposures in operations where Hexavalent chromium may accumulate on surfaces, the employer shall institute a housekeeping program in accordance with 1910.1026(j). In addition, whenever an employer allows employees to consume food or drinks at a worksite where Hexavalent chromium is present, the employer must “ensure that eating and drinking areas and surfaces are maintained as free as practicable of Hexavalent chromium.” To meet this requirement, the employer must establish hygiene practices, such as regular cleaning, for eating and drinking areas.
It is suggested that an employer collect dust wipe surface samples to evaluate the efficacy of its hygiene practices and ensure surfaces are free from accumulations of Hexavalent chromium. It is noted the standard does not require the collection of surface wipe samples to be performed or specify the allowable surface loading of Hexavalent chromium. However, surface wipe sampling may prove beneficial, as it can be used as a means to ensure surfaces are “as free as practical” from accumulations of Hexavalent chromium. Brookhaven National Laboratories has suggested a guidance concentration of 50 micrograms per 100 square centimeters for operational areas and a concentration of 3.3 micrograms per 100 square centimeters for non-operational areas (IH75190 “Surface Wipe Samples for Metals”).
In order to minimize exposure to Hexavalent chromium accumulations, contaminated surfaces must be cleaned regularly. Work surfaces should be cleaned by applying wet methods, such as wet wiping, wet sweeping or wet scrubbing. Vacuuming should only be used when using a High Efficiency Particulate Air Filter (HEPA) equipped vacuum. Employers must evaluate the specific hazards in their workplaces to determine the frequency and type of cleaning required to maintain eating and drinking areas and surfaces as free as practicable of chromium (VI) contamination.
Resources:
- Hexavalent Chromium. OSHA Publication 3373, (2009).
- SS-835 Hexavalent Chromium. Saif, (2018).
- Clarification of the Chromium (VI) Standard – Change Rooms and Hygiene Practices. [1910.141; 1910.141(e); 1910.1026; 1910.1026(h)(1); 1910.1026(i)(1)]. (September 2, 2011).
- 1910.1026(d)(2) – Clarification of monitoring and sampling requirements for hexavalent chromium. – (09/30/2010)
- IH75190, “Surface Wipe Sampling for Metals,” Rev. 23, Brookhaven National Laboratory, 06/23/17