Exposure Risks and Reactions
Workers may be exposed to hex chrome through inhalation (of dusts, mists or fumes); ingestion; or dermal or eye contact (with dusts or liquids). Health effects associated with exposure to hex chrome can include irritation or damage to the skin and eyes.
Direct skin contact can cause an allergic reaction called contact dermatitis. Once an allergy develops, even brief skin contact can cause symptoms. Direct skin contact also can cause non-allergic skin irritation called chrome ulcers, which are small sores that heal very slowly and leave scars. Additional health effects can include irritation or damage to the nose and throat.
Prolonged exposure to hex chrome may result in sores, nosebleeds and even holes in the septum (nasal wall). Hex chrome exposure also can cause irritation or damage to the lungs. Inhaling chromate compounds may cause asthma symptoms such as wheezing and shortness of breath. Prolonged exposure may cause lung cancer.
Paints with small percentages of chromate compounds have been found with the potential to exceed airborne occupational exposure limits (OELs) for hex chrome. In particular, painting operations utilizing a compressed air sprayer, which aerosolizes the paint, can present an inhalation and skin hazard. In addition, welding work on stainless steel also has been found with the potential to exceed airborne OELs for hex chrome. A proper assessment of the hazard therefore should be conducted in order to evaluate the potential risk with these operations.
Hex chrome’s qualities – widespread occurrence, continued use, health effects and low exposure limits – make it a good example of steps that are effective in managing a wide range of workplace hazards.
What Works – and What Doesn’t?
Effective measures to protect workers from hex chrome-related hazards should follow the hierarchy of controls:
Elimination: Best practice entails eliminating a workplace threat whenever possible. This might include substituting hazard-free materials for those that may present a risk. In some cases, elimination might include phasing out products that contain the hazardous material. This might work in the case of another welding-related hazard, manganese (welding rods), but the ubiquity of chromium, which can be converted to the hexavalent form when heated to welding temperatures, renders elimination impractical in many cases.
Engineering Controls: If the hazard cannot be eliminated, exhaust fans and hoods may help reduce airborne exposure, or paint rooms may be ventilated separately from the rest of the workplace. However, relying on engineering controls that are not properly set up and periodically evaluated still may result in exposure.
Administrative Controls: A good example of this type of control is training. Exposure can be greatly reduced by educating workers to avoid exposure by body positioning and minimizing other staff in the area where exposure may occur.
Personal Protective Equipment (PPE): This is least-preferred method since it places more responsibility on the worker. In addition, regulations are triggered when using specialized PPE, such as respiratory protection, which can present complications.
Equipment and Culture
Industrial hygienists sometimes face the challenge of engineering control measures only being partially effective. This might include installation of an inadequate or inappropriate ventilation system.
One root cause of the problem is that employers too often rely on the recommendations of equipment manufacturers or mechanical contractors rather than getting advice from a qualified industrial hygienist. Such a professional, with ventilation experience, is up-to-date on recommended practices and is able to offer unbiased advice.
Some companies have the capacity to retain IH professionals on staff. These professionals have the advantage of being familiar with the company’s procedures, culture and what will work within the limitations of the company. This particularly is true in the case of hex chrome, which presents a wide range of situations in which workers can become exposed. Keeping employees safe requires a solid understanding of the specific workplace in question, so their efforts may be more effective given the realities including company culture.
In-house IH professionals also may be familiar with the company’s plans, such as the intention to increase production, so new purchases and retrofits can be made in a way that the company can remain compliant when expansion occurs.
An external IH professional, in contrast, likely will have the advantage of wider experience of how hazards have been dealt with at other workplaces. This person also may have been able to acquire more specialized knowledge about regulations and be familiar with trends than an internal person could be – particularly if the in-house person must wear “hats” other than the industrial hygiene function. Overall, balance of internal resources and external expertise depends on the situation at each workplace.
In addition to the right equipment, the right culture needs to be in place. Workers should feel engaged in their safety programs and offer ideas to reduce or eliminate hazards. Employers should consider implementing effective programs to manage hazards such as hex chrome. Creating such a program should involve management and those employees who are expected to abide by the program.
A company culture that leads with safety may be years in the making, but is well worth it in terms of employee morale, reduced injuries and the success of the company.
Aaron Rogers, ASP is a project scientist/industrial hygienist with Golder Associates Inc., in the Jacksonville, Fla., office. He can be reached at 904-363-3430 or [email protected].