On February 21, the U.S Occupational Safety and Health Administration (OSHA) released a new guidance document titled Preventing Skin Problems from Working
On February 21, the U.S Occupational Safety and Health Administration (OSHA) released a new guidance document titled Preventing Skin Problems from Working with Portland Cement. Available at www.osha.gov/dsg/guidance/cement-guidance.html, the document was created to educate employers and employees regarding prevention of skin-related problems while working with cement. No additional rulemaking is anticipated as a result of this publication.
That wet concrete can damage skin, primarily due to its caustic nature, is well known to producers. OSHA now advises that trace amounts of hexavalent chromium contained in cement also are harmful to skin and may be an underlying cause of allergies some persons develop to cement. According to OSHA, cement accounts for approximately 25 percent or more of all work-related skin problems, while occupational skin disorders constitute an estimated 10-15 percent of all work-related diseases.
The new program identifies methods to prevent, or minimize, skin problems through proper selection and use of personal protective equipment, including gloves, boots, and kneepads. Also provided is guidance on proper skin care and work practices, such as use of pH-neutral or slightly acidic soaps, as well as ways to fabricate less hazardous cement-containing products.
Wet concrete can cause caustic burns, resulting in blisters, dead or hardened skin, and black or green skin discoloration. Contact with wet concrete sometimes does not cause pain or discomfort until the cement burn is somewhat severe. In addition to cement burns, wet concrete can cause dermatitis whose effects include itching, redness, swelling, blisters, scaling, and other changes in the normal condition of the skin.
For persons apparently allergic to cement, a reaction is triggered actually by trace amounts of hexavalent chromium, or Cr(VI), which is contained in cement. Thus, the immune system of a sensitized employee overreacts to small amounts of Cr(VI), which can lead to severe inflammatory reactions upon subsequent exposures. Sensitization may result from a single Cr(VI) exposure or repeated exposures over the course of months or years Û or, it may not occur at all. After an employee becomes sensitized, brief skin contact with very small amounts of Cr(VI) can trigger acute chronic dermatitis (ACD).
All producers have known persons who became Îallergic to cement,Ì now known as ACD to Cr(VI). In some cases, the severity is great enough to render an employee unable to continue working in the concrete industry. ACD is reportedly long-lasting, and employees can remain sensitized to Cr(VI) years after exposure to cement has occurred. Medical skin patch tests are available that can confirm whether an employee has become dermally sensitized to Cr(VI).
In hot summer weather, the problem is most prevalent, as workers perspire and cement dust adheres to the skin. When CR(VI) enters into solution under such conditions, prolonged skin contact inevitably results.
Producers should be aware that the Hazard Communication regulation requires provision of training to all workers who may be exposed to cement. (Compliance with regulations requiring prompt reporting of health-related incidents is also necessary.) The training must be documented and provide the following information and/or components:
- Hazards associated with exposure to cement, including those associated with the cement’s Cr(VI) content
- Measures to prevent exposure, including proper use and care of PPE, as well as the importance of proper hygiene practices
- Employee access to hygiene facilities, PPE, and relevant data (including MSDSs)
- Procedures for reporting work-related injuries, illnesses, and all cases of cement burns, dermatitis, or allergic reactions.
OSHA has established permissible exposure limits (PEL) for inhalation of dry portland cement at 15 milligrams per cubic meter (mg/m3) of air for total dust and 5 mg/m3 for respirable dust. Because the Cr(VI) content in portland cement is extremely low, meeting the permissible exposure limit (PEL) of 15 mg/m3 for portland cement will enable employers also to meet a Cr(VI) PEL and action level of 5 and 2.5 micrograms, respectively, per cubic meter (µg/m3).
The only way to document airborne cement-dust exposure is to enlist a Certified Industrial Hygienist to conduct airborne monitoring at all plant stations. Even if no exposures are found to exceed the PEL, monitoring should be conducted periodically Û and at different times of the year Û to ensure that changing conditions do not create a dust-exposure problem. Among factors or circumstances that could alter atmospheric conditions are humidity; open bay doors, allowing wind to create dust; operational or equipment changes, e.g., increased forklift traffic stirring up floor dust; or, other conditions that may cause an obvious or subtle change in dust exposure.
Producers should avoid flushing floor dust into the yard or out bay doors, since mobile traffic is notorious for pulverizing and spreading dust once the wash debris dries, generating considerable airborne matter. Employees should be trained to sweep floors correctly, using a broom stroke that stops the broom on the floor at the end of the stroke rather than flipping the broom at the end of the stroke to throw the dust ahead. For extensive pavements in the shop, floor sweeping machines employing a wet-vac system provide an effective solution, although the abrasive qualities of cement and concrete dust can shorten the life of sweepers. Repairing all conveyor drips and leaks, while maintaining a vacuum-filtration system on the mixers, is also crucial to optimal dust control.
Butyl or nitirile nonporous gloves are suitable, but not those fabricated of cotton or leather. Light disposable cotton liners are excellent for use inside nonpervious gloves to wick perspiration and provide warmth in winter conditions. Additionally, employees should wash and thoroughly dry their hands before putting on gloves and immediately after taking them off. Specific methods for wearing and removing gloves should be reviewed with employees, so contaminated parts of the glove are not handled inadvertently.
Producers should also consider requiring employees to wear long-sleeved shirts to minimize dust exposure. Any work clothes contaminated with wet cement or excessive dust should be changed and kept separate from street clothes to prevent cross contamination. OSHA advises that using barrier creams is not effective for cement dust exposure, since airborne matter simply mixes with the ointment and remains stuck to the skin.
A common source of exposure is wet leather boots. The Cr(VI) in cement enters into solution and soaks with the water through a leather boot, resulting in cement burns to the feet. Such burns can be severe, since initial contact is painless. Thus, producers should ensure that all employees wear boots covering the ankles and that rubber boots are used in wet conditions to keep water off leather or fabric footwear.
When kneeling on wet cement, wet production floors, or dry dusty floors, personnel should use waterproof kneepads or dry kneeboards to prevent the knees from coming into contact with cement. Workers should also wear proper eye protection when working with cement. Besides allergic reactions to cement, dust particles lodged in the eye present a common problem among plant employees.
Soap selected for use in concrete plants should be pH neutral to slightly acidic Û not including abrasive or waterless hand cleaners, such as alcohol-based gels or citrus cleaners. OSHA strongly advises against the use of lanolin, petroleum jelly, or other skin-softening products, because these substances can seal cement residue to the skin, increase the skin’s ability to absorb contaminants, and cause irritation. Similarly, skin-softening products should not be used to treat cement burns.
Plants should also consider prohibiting rings or watches, since dust and sweat tend to collect under such items. Moreover, prohibiting jewelry is recommended, due to the serious electrical burn hazard associated with conductivity of the metal against a live circuit. The hazard of injury or amputation associated with machinery snagging the jewelry or a protrusion catching it warrants consideration.
Cement dust is now known to contain (1) small amounts of Cr(VI), which can cause ACD in some persons, as well as (2) respirable silica, a cause of silicosis. Accordingly, producers are required to implement additional measures to control airborne dust and minimize employees’ dust exposure.
PLANT POLICY GUIDELINES, BEST PRACTICES
- Require long-sleeved shirts and long pants
- Require ANSI-approved safety boots that cover the ankles
- Require wearing of ANSI-approved safety rubber boots in wet conditions
- Require use of impervious gloves with disposable cotton liners when working with concrete or cement
- Require knee pads when kneeling
- Require safety glasses with side shields
- Require additional PPE including hardhat, face shields when grinding, welding PPE, and other items appropriate to the task
- Employees should wash and thoroughly dry their hands before putting on gloves and immediately after taking them off.
- Work clothes that become contaminated with cement paste or excessive dust should be changed and kept separate from street clothes to prevent cross contamination.
Including watches, bracelets, rings and necklaces
BEST PLANT PRACTICES
- Do not wash nor sweep production floor material or dust onto the yard or drive areas.
- Shovel all concrete chips and bits, so they do not become pulverized by mobile equipment.
- When the yard becomes dusty due to the pulverizing action of mobile equipment and truck traffic, scrape off and dispose of the dusty top layer of the yard, replacing it with new crushed stone, if necessary.
- Select hand soaps that are pH neutral or slightly acidic. Soaps should not contain abrasives nor be waterless hand cleaners, such as alcohol-based gels or citrus cleaners.
- Periodically enlist a Certified Industrial Hygienist to conduct personal dust-exposure monitoring.
- Add inspection for dust leaks and conveyor leaks to plant checklists.
- For producers that can afford it, providing a change room and uniforms with a daily wash schedule would be ideal.
- Conduct plant best practice procedures training and verify that regulatory training is documented.