Hexavalent Chromium
Protect your workers by reducing exposure.

OSHA has published detailed compliance requirements for lowering Hexavalent Chromium exposure, also known as Hexavalent Chrome, Chromium 6, Chromium VI, and Cr(V1). It is important to note that the deadline for implementing engineering controls is May 31, 2010. 1910.1026 Chromium (VI)*.

What does it all mean?
The new OSHA Hexavalent Chromium standards apply to all occupational exposures to Cr(V1) with very limited exceptions. Although OSHA has established separate Hexavalent chromium standards for Chromium 6 exposure for the sectors of general industry, construction and shipyards most of the requirements are the same. OSHA has legislated the lowering of Chromium VI exposure limits based on findings that workers exposed to Cr(V1) suffer increased risk of serious health effects. It has now been well documented by the EPA that Hexavalent Chromium is an IARC-1 human carcinogen.

Cr(V1) is present in many types of compounds used in a variety of industrial and commercial applications. In the "hot work" of the welding process some materials such as stainless steel change chemically. In this example the chromium is not originally hexavalent but is converted by the high temperatures involved so it is important to know your materials as well as your processes. Suppliers should be able to supply MSDS sheets if you have questions about material being used.

In measurable terms the new OSHA Hexavalent Chromium standard for PEL or Permissible Exposure Limit has been established as: an 8-hour time-weighted average exposure limit of 5 micrograms of Cr(V1) per cubic meter of air (5 µg/m3). In other words, the average exposure to Cr(V1) cannot exceed (5 µg/m3) over the course of an 8 hour work shift. (See Table 1 below for calculation information).

OSHA Hexavalent Chromium Standards indicate that employers must use engineering and work practice controls as the first means to reduce and maintain employee exposures to Cr(VI) to or below the established PEL. Engineering controls include:

  • Substitution (materials or processes)
  • Isolation (enclosing the source or establishing barriers)
  • Ventilation (local exhaust or general ventilation)

What types of ventilation equipment is available?
The new standard for PEL of (5 µg/m3)or 0.005 mg/m3 although understandable, is certainly low. Contrary to common practice, attempts to reduce exposure by setting up fans or opening up windows and doors have been proven to be ineffective ways to protect workers. Unless engineering controls are in place, many welding and thermal cutting tasks are likely to require supplied air respiratory protection. Most people in the industrial arena are very aware of the physiological challenges that respirators place on workers such as limiting auditory, visual, and odor perception.

At Industrial Maid we manufacture tested and proven fume extractors that, when in place as engineering controls, will be key to compliance with OSHA Hexavalent Chromium standards. In simple terms our air filtration systems efficiently source capture toxic fumes and gases and remove them so that they never enter the welder's breathing space. Of utmost importance to note when striving for the new lower PEL standard, our RH & RHV Series Hoods, EB 56 Side Drafts, and T-Series models can be fitted with final Hepa's filters.

We understand that many employers are concerned about the potential expense involved in making sure they are compliant with the new OSHA Hexavalent Chromium standards. But it has been proven that finding the right industrial ventilation equipment and placing it in the right application saves operating dollars. Talk to one of our engineers at Industrial Maid (877-624-3247) and find out how we strive to help our customers select the right products and consider the "overall cost of ownership". The end result of which is reduced capital expense and lowered operating costs.

Our full line of industrial ventilation systems include ventilation hoods, ducted overhead units, portables, ambient air cleaners or backdraft units, filter walls and booths.

Calculation of Time-Weighted Average Exposures

Both the PEL and the action level are expressed as time-weighted average (TWA) exposures. TWA measurements account for variable exposure levels over the course of a work shift, averaging periods of higher and lower exposures. The TWA exposure for an 8-hour work shift is computed using a simple formula:

TWA = (CaTa+CbTb+...CnTn)÷8

Where:
TWA is the time-weighted average exposure for the work shift;
C is the concentration during any period of time (T) where the concentration remains constant; and
T is the duration in hours of the exposure at the concentration (C).

For example, assume that an employee is subject to the following exposure to Cr(VI):

Two hours exposure at 10 µg/m3
Two hours exposure at 5 µg/m3
Four hours exposure at 1 µg/m3

Substituting this information in the formula, we have:

(2x10 + 2x5 + 4x1)÷8 = 4.25 µg/m3

Since 4.25 µg/m3 is more than 2.5 µg/m3, the action level has been exceeded. However, as 4.25 µg/m3 is less than 5 µg/m3, the PEL has not been exceeded.

Table 1: Calculation of Time-Weighted Average Exposures (pg. 6)
OSHA Publication:Small Entity Compliance Guide for the Hexavalent Chromium Standards

Now how do I go about selecting the right Industrial Air Cleaner?
What happens after you have done all of the testing and research and determined that you need an industrial air cleaning system that protects your welders from Chromium 6 or any and all types of welding smoke and fumes? What happens when you have looked at all the different types of welding smoke ventilation units but you just aren't sure what best fits your needs? Click on this Selection Guide to see a simple guide to finding the fume extractor that will serve you best. Then give us a call at Industrial Maid 877-624-3247 and get friendly free consultation from engineers with a combined 32 years experience in the air filtration and welding supply industries.

OSHA implements a National Emphasis Program to address Hexavalent Chromium

Other important areas of compliance with OSHA Hexavalent Chromium standards include regulated areas, respiratory protection, protective work clothing and equipment, hygiene areas and practices, housekeeping, medical surveillance, recordkeeping, compliance dates and communication of Chromium 6 hazards to employees.OSHA has made an abundance of information available regarding OSHA welding standards and related topics which can be accessed through the links provide on this page or go to www.osha.gov.

A National Emphasis Program has been set up by OSHA to help pinpoint and eliminate dangerous health issues associated with worker exposure to hexavalent chromium. Personnel from OSHA staff will oversee inspections and offer compliance assistance and outreach where it is determined that employees are likely to be exposed to Cr(V1). OSHA has also published a directive which requires employers to notify employees of any exposure to hexavalent chromium even if it falls outside of the allowable exposure limit. View the notice.

*For more details and contact information for complying with the Hexavalent Chromimium standards refer to the Small Entity Compliance Guide for the Hexavalent Chromium Standards published by OSHA.