Occupational Exposure to Cadmium in the Construction Industry
Construction Safety and Health
Outreach Program |
U.S. Department of Labor
OSHA Office of Training and Education
May 1996 |
INTRODUCTION
In its elemental form, cadmium is either a blue-white metal or a grayish-white powder found in lead, copper, and zinc
sulfide ores, but most cadmium compounds are highly colored from brown to yellow and red. Cadmium's uses vary from an
electrode component in alkaline batteries to a stabilizer in plastics.
In 1971, the Occupational Safety and Health Administration (OSHA) moved to protect cadmium-exposed employees by
adopting the American National Standards Institute's threshold limit values (TLVs) for cadmium as a national
consensus standard under section 6 (a) of the Occupational Safety and Health (OSH) Act of 1970. The consensus
standard established for the construction industry an 8-hour time-weighted average (TWA) permissible exposure limit
(PEL) of 100 micrograms of cadmium per cubic meter of air (100 µg/m3) for cadmium oxide fumes and 200
micrograms of cadmium per cubic meter of air (200 µg/m3) for metal dust and soluble salts. Several
studies, however, provided evidence of lung cancer and kidney disease from occupational exposure to cadmium at and
below these established PELs.
In July 1987, OSHA determined the need for a rulemaking under section 6 (b) of the OSH Act to reduce worker exposure
to cadmium. In 1990, OSHA published a notice of proposed rulemaking on cadmium to establish a PEL of either 5 µg/m3
or 1 µg/m3, to reduce the level of worker exposure to cadmium by more than 95 to 99 percent.1
The PEL is a TWA concentration that must not be exceeded during any 8-hour work shift of a 40-hour workweek.
On September 14, 1992, OSHA published in the Federal Register a final rule for cadmium in
the construction industry under Title 29 Code of Federal Regulations Part 1926.63.2
The rule, effective December 14, 1992, establishes a PEL of 5 µg/m3 for all cadmium compounds, including
dust and fumes, and other protective provisions for cadmium in the construction industry. The rule also establishes
the action level, which is defined as a level of cadmium in the air of the workplace that is half of the PEL, or 2.5
µg/m3, calculated as an 8-hour TWA. If exposure occurs at or above the action level, employers must
determine the airborne level and follow the provisions in the rule applicable to that level, such as providing
medical surveillance, performing air monitoring, and providing a respirator to any employee who requests one.
OSHA estimates that approximately 70,000 employees in the construction industry are potentially exposed to cadmium.3
OSHA developed a separate standard regulating exposure to cadmium in the construction industry to reflect differences
between general industry and construction operations and operations of various types within the construction
industry. In recognition of this wide diversity in construction projects, OSHA specifically identified, in the final
rule, those additional requirements that apply to such construction operations. For example, the construction
industry is characterized by non-fixed worksites that are temporary in nature and differ from those in general
industry in regard to the need for a designated competent person as well as significant differences between
workplaces in terms of site conditions, size and scope of tasks, methods of operation, and environmental conditions.
Furthermore, employees in the construction industry often do not remain in construction or in the employ of the same
employer for a long period of time, in contrast to employees in fixed-site manufacturing facilities. Thus, the
special characteristics of construction operations made it necessary to tailor some of the requirements traditionally
included in OSHA health standards to the specific needs of the construction industry.
SCOPE AND APPLICATION
The final cadmium rule for the construction industry applies to all occupational exposure to cadmium and all cadmium
compounds in all forms, including fumes and dusts, and in all construction work where an employee may be potentially
exposed to cadmium. Such work involves construction, alterations, and repairs. The activities include, but are not
limited to, wrecking, demolishing, and salvaging structures where cadmium or cadmium-containing materials are
present; cutting, brazing, grinding, or welding on surfaces that are painted with cadmium-containing paints; and
transporting, storing, and disposing of cadmium or cadmium-containing materials on the site or location where
construction activities are performed.
PROVISIONS OF THE RULE
The cadmium rule for the construction industry contains many of the same requirements as those for general industry,
such as the aforementioned exposure limits, and provisions pertaining to respiratory protection, emergency
situations, protective work clothing and equipment, housekeeping, and hygiene facilities.4
These items are highlighted as follows:
- Respiratory Protection. Where applicable, the employer must provide respirators at
no cost to employees and ensure that they are used in compliance with the standard.5
Powered air-purifying respirators must be provided to employees who request them and where this respirator will
provide adequate protection. Employers must ensure that employees use respirators in regulated areas and that
respirators are properly fitted and used. Employees required to wear respirators must have limited medical exams
prior to being assigned to an area where respiratory protection is required unless they have had a comparable exam
within the preceding 12 months. Employees must be allowed to leave a regulated area to readjust face pieces and to
change filters or to wash their faces to avoid skin irritation.
- Emergency Situations. Employers must develop and implement a written plan for
emergency situations involving substantial releases of airborne cadmium.
- Protective Work Clothing and Equipment. Employers must provide protective clothing
and equipment—such as coveralls, shoe covers, head coverings, and goggles—for employees exposed above the PEL
and for employees with skin and eye irritation from cadmium exposure. The employer must ensure that contaminated
clothing and equipment are placed in closed containers in change rooms prior to cleaning, laundering, maintaining,
or discarding. The employer must provide clean and dry personal protective clothing and equipment at least weekly,
or more often, as necessary to maintain effectiveness. The employer must notify those who launder or clean these
items of the potential hazards of cadmium exposure.
- Housekeeping. Employers must maintain all surfaces as free as practicable of
accumulations of cadmium and clean up spills promptly. Compressed air may be used to clean up accumulations of
cadmium if it does not disperse cadmium into the air; vacuuming using a high-efficiency particulate air filter is
preferable. The employer also must ensure that waste, scrap, debris, bags, containers, equipment, and clothing
contaminated with cadmium and consigned for disposal be collected and disposed of in sealed impermeable bags or
other closed impermeable containers. These bags and containers must be labeled according to the provisions of the
rule, and disposed of according to applicable federal, state, and local regulations.
- Hygiene Facilities and Practices. The employer must provide facilities for showering
and handwashing, change rooms, and lunch rooms for employees exposed above the TWA PEL. Change rooms must be
equipped with separate storage facilities for street clothes and personal protective clothing/equipment and must be
designed to prevent dispersing cadmium and contaminating the employee's street clothes. The lunch area should be
readily accessible to employees. The level of cadmium in lunch areas must be below the action level of 2.5 µg/m3.
Before entering the lunch area, employees must clean or remove their protective clothing by HEPA vacuuming or some
other removal method that does not disperse cadmium into the air. Also, employees exposed to cadmium above the PEL
must shower at the end of the work shift and must wash their hands and faces prior to eating, drinking, smoking,
chewing tobacco or gum, or applying cosmetics.
Other provisions are included to deal with the differences in job duration, worker exposure,
and work site conditions in the construction industry. These provisions include (1) designating a competent person on
a construction site; (2) conducting exposure monitoring; (3) establishing regulated areas; (4) establishing
compliance methods; (5) conducting medical surveillance; (6) communicating cadmium hazards to employees; (7) keeping
exposure and medical records; and (8) delaying, in certain
instances, the effective date of specific provisions of the rule.
Competent Person
OSHA established a "competent person" provision in the construction cadmium standard because there were no
accurate exposure data available regarding the average length of exposure per week, the exposure levels, and the
worker turnover in various job categories. The standard, therefore, requires employers to designate a person capable
of identifying existing and potential cadmium hazards in the workplace and taking prompt, corrective actions to
eliminate or control such hazards.
The designated "competent person" must be able at least to (1) determine, prior to beginning a job, whether
cadmium is present in the workplace; (2) establish regulated areas and ensure that access to and from those areas is
limited to "authorized" employees; (3) ensure the adequacy of any employee exposure monitoring required by
the standard; (4) ensure that all employees exposed to airborne cadmium levels above the PEL wear the appropriate
personal protective equipment and are trained to use appropriate methods to control cadmium exposure; (5) ensure that
proper hygiene facilities are provided and that workers are trained to use these facilities; and (6) ensure that
required engineering controls are implemented, maintained in proper operating condition, and functioning properly.
Exposure Monitoring
There are four significant exposure monitoring provisions of the cadmium standard for construction: (1) prior to
performing any construction work where employees may be exposed to cadmium, the employer must determine—through a
designated competent person—whether cadmium is present in the workplace, and whether there is a possibility that an
employee may be exposed to cadmium at or above the action level; (2) if the employee periodically performs tasks that
may expose him or her to a higher concentration of airborne cadmium, the employer must monitor the employee while
performing those tasks; (3) no minimum frequency for monitoring is required under the construction industry's cadmium
standard (e. g., the changing nature of job and work conditions often limit the value of periodic monitoring on a
fixed schedule); and (4) the employer shall notify each affected employee, in writing, of the results and shall post
the results in an appropriate location accessible to affected employees, no later than 5 working days after receiving
the results of any monitoring that is performed.
Regulated Areas
Whenever an employee is or can reasonably be expected to be exposed to cadmium in excess of the PEL, the employer is
required to establish a regulated area alerting employees to the hazards.
Regulated areas must:
- Be set apart from the rest of the workplace in a way that establishes and alerts employees to the boundaries of
the area;
- Be entered ONLY by authorized persons;
- Be entered ONLY by persons using proper respirators; and,
- Be accessible to employees who refrain from eating, drinking, smoking, chewing tobacco or gum and applying
cosmetics in such areas. Employees must not carry, store, or use products associated with such activities in these
areas.
Warning signs bearing the following information must be posted at all approaches to regulated
areas:
DANGER...CADMIUM...CANCER HAZARD...CAN
CAUSE LUNG AND KIDNEY DISEASE...
AUTHORIZED PERSONNEL ONLY...RESPIRATORS
REQUIRED IN THIS AREA. |
OSHA requires that employers consider establishing regulated areas whenever the following construction activities are
conducted:
- Electrical grounding with cadmium welding;
- Cutting, brazing, burning, grinding, or welding on surfaces that are painted with cadmium-containing paints;
- Electrical work using cadmium-coated conduits;
- Using cadmium-containing paints;
- Cutting and welding cadmium-plated steel;
- Brazing or welding with cadmium alloys;
- Fusing of reinforced steel by cadmium welding;
- Maintaining or retrofitting cadmium-coated equipment; and
- Wrecking and demolishing where cadmium is present.
Methods of Compliance
Employers must implement engineering and work practice controls to reduce and maintain worker exposure to cadmium at
or below the PEL. Engineering controls might include installing equipment, (e. g., source point capture) or modifying
a process, (e. g., enclosure) to control employee exposure levels. Work practice controls include practices such as
not eating, drinking, or applying cosmetics in regulated areas.
Some of the provisions that employers must adhere to include, but are not limited to, not using high-speed abrasive
disc saws and similar abrasive power equipment unless such equipment has the appropriate engineering controls to
minimize emissions and to meet the PEL. Materials containing cadmium shall not be applied by spray methods, if
exposures are above the PEL, unless employees are protected with certain specified respirators and measures are taken
to limit overspray and prevent contamination of adjacent areas.
Written Compliance Program
A written compliance program must be established and implemented that describes how the employer will reduce employee
exposure to the PEL or below by the use of engineering and work practice controls and by the use of respiratory
protection where permitted.
The written compliance program must be reviewed and updated as often and as promptly as necessary to reflect any
significant changes in the employer's compliance status. A designated "competent person" shall review the
compliance program, initially and after each change, to ensure that the written program offers adequate employee
protection from occupational exposure to cadmium.
Upon request, the written compliance program must be made available for examination and copying to the Assistant
Secretary for OSHA, the Director of the National Institute for Occupational Safety and Health (NIOSH), and affected
employees and their designated representatives.
Medical Surveillance
All construction employees are automatically covered by the medical surveillance provisions if, for 30 days or more
per year, they perform any of the tasks, operations, or jobs for which employers are required to establish regulated
areas (see section on Regulated Areas for a listing of these construction activities).
Employers also must provide medical surveillance to all employees who might have been exposed to cadmium by the same
employer prior to the effective date of the standard in any of the tasks, operations, and jobs previously listed
under Regulated Areas. Otherwise, the current employer must demonstrate that the employee
did not, in the years prior to the effective date of the standard, work for the employer in those tasks for an
aggregated total of more than 12 months prior to the effective date of this standard. If biological monitoring
results are abnormal, employers must, among other things, reassess employee exposures within 30 days.
Employers must temporarily remove employees from jobs with exposure to cadmium at or above the action level on each
occasion that a physician determines in a written medical opinion that the employee should be removed from cadmium
exposure or in cases where the employee's biological monitoring results are so high as to require mandatory medical
removal. The physician may determine the need for medical removal based on biological monitoring results, evidence of
illness, inability to wear a respirator, signs or symptoms of cadmium-related dysfunction or disease, or any other
reason deemed medically sufficient. When the removal is due to the employee's inability to wear a respirator, the
removal need only be from jobs with exposure to cadmium above the PEL.
Where an employee temporarily is medically removed from a job for reasons related to cadmium exposure, the employer
must remove the employee from any job where exposure is at or above the action level and must provide medical removal
benefits such as normal earnings, seniority, and employee rights for a maximum of 18 months.
Cadmium Hazard Communication
Employers in the construction industry must communicate to employees the hazards of occupational exposure to cadmium.
In a multi-employer workplace, however, an employer who produces, uses, or stores cadmium in a manner that may expose
the employees of other employers to cadmium is required to notify the other employers of the potential hazard in
accordance with the provisions outlined in the hazard communication standard for construction in 29 CFR 1926.59.
The cadmium standard requires regulated areas to be posted with appropriate warning signs. Because the nature of
construction work and the hazards often associated with it often change dramatically in the course of completing a
project, regulated areas also may need to be established on a temporary basis. Therefore, using warning signs is
especially important because employees who are regularly scheduled to work in or near these areas need to be warned
about exposure to cadmium at or above the PEL.
Recordkeeping
Recordkeeping provisions in the cadmium standard for construction require employers to establish and keep an accurate
record of all air monitoring for cadmium in the workplace. The employer must maintain this record for at least 30
years in accordance with the requirements for access to employee exposure and medical records (29 CFR 1910.1020). In
addition, under the cadmium standard, employers must provide a copy of the employee's air monitoring results to an
industry trade association and to the employee's union or a comparable organization that is competent to maintain
such records and is reasonably accessible to employers and employees in the industry.
The employer also must establish and maintain an accurate record for each employee covered by the medical
surveillance provisions of the cadmium standard [29 CFR 1926.1127(l)(1)(i)]. The employer must maintain these
records for the duration of employment plus 30 years in accordance with 29 CFR 1910.1020. The cadmium standard also
requires that the employer, at the employee's request, provide a copy of the employee's medical record or update, as
appropriate, to a medical doctor or union specified by the employee.
These provisions help ensure that workers in an industry with short-term employment, relatively high rates of
turnover, and mobile job sites have a stable backup source for obtaining these records, if needed.
CONCLUSION
OSHA has determined that cadmium in any form poses a significant threat to the health of workers and can result in
kidney damage, lung cancer, or respiratory diseases. OSHA expects that this standard will reduce workers' potential
risk of serious health effects from cadmium exposure.
1. Federal Register 55 (25): 4052-4147 on February 6, 1990.
2. This discussion is not a substitute for requirements of the rule. The complete regulatory text
of the cadmium rule and appendices are published in the Federal Register 57 (178):
42102-42463.
3. OSHA, Office of Regulatory Analysis, 1992.
4. A complete discussion of these provisions is found in the general industry standard, which was
published on September 14, 1992, in the Federal Register under Title 29 CFR Part 1910.1027.
5. See 1926.63, section (g)(1) for respirator use.