Are pulmonary function tests (PFT) an OSHA Requirement?

Pre-Employment Screening

Pre-employment screening has two major functions:

1. determination of an individual’s fitness for duty, including the ability to work while wearing protective equipment, and

2. provision of baseline data for comparison with future medical data.

Determination of Fitness for Duty

Workers at hazardous waste sites are often required to perform strenuous tasks (e.g., moving 55-gallon drums) and wear personal protective equipment, such as respirators and protective clothing, that may cause heat stress and other problems (see Chapter 8 for details). To ensure that prospective employees are able to meet work requirements, the pre-employment screening should focus on the following areas:

Occupational and Medical History

• Make sure the worker fills out an occupational and medical history questionnaire. Review the questionnaire before seeing the worker. In the examining room, discuss the questionnaire with the worker, paying special attention to prior occupational exposures to chemical and physical hazards.
  
• Review past illnesses and chronic diseases, particularly atopic diseases such as eczema and asthma, lung diseases, and cardiovascular disease.
  
• Review symptoms, especially shortness of breath or labored breathing on exertion, or other chronic
  respiratory symptoms, chest pain, high blood pressure, and heat intolerances.
  
• Identify individuals who are vulnerable to particular substances (e.g., someone with a history of severe asthmatic reaction to a specific chemical).
  
• Record relevant lifestyle habits (e.g., cigarette smoking, alcohol, and drug use) and hobbies.

Physical Examination

• Conduct a comprehensive physical examination of all body organs, focussing on the pulmonary, cardiovascular, and musculoskeletal systems.
  
• Note conditions that could increase susceptibility to heatstrokes, such as obesity and lack of physical exercise.
  
• Note conditions that could affect respirator use, such as missing or arthritic fingers, facial scars, dentures, poor eyesight, or perforated eardrums.

Ability to Work While Wearing Protective Equipment

• Disqualify individuals who are clearly unable to perform based on the medical history and physical exam (e.g., those with lung disease, heart disease, or back or orthopedic problems).
• Note limitations concerning the worker’s ability to use protective equipment (e.g., individuals who must wear contact lenses can not wear full facepiece respirators).
• Provide additional testing (e.g., Chest X-ray, pulmonary function testing, electrocardiogram) for the ability to wear protective equipment where necessary.
• Base the determination on the individual worker’s profile (e.g., medical history and physical exam, age, previous exposures, and testing).
• Make a written assessment of the worker’s capacity to perform while wearing a respirator if wearing a respirator is a job requirement. Note that the occupational Safety and Health Administration (OSHA) respirator standard 29 CFR Part 1910.134) states that no employee should be assigned to a task that requires the use of a respirator unless it has been determined that the person is physically able to perform under each condition.

Baseline Data for Future Exposures

Pre-employment screening can be used to establish baseline data to subsequently verify the efficacy of protective measures and to later determine if exposures have adversely affected the worker. Baseline testing may include both medical screening tests and biologic monitoring tests. The latter (e.g., blood lead level) may be useful for ascertaining pre-exposure levels of specific substances to which the worker may be exposed and for which reliable tests are available. Given the problem in predicting significant exposures for these workers, there are no clear guidelines for prescribing specific tests. The following approach identifies the types of tests that may be indicated:

• A battery of tests based on the worker’s past occupational and medical history and an assessment of significant potential exposures. See Tabla 5-3 for examples of tests frequently performed by occupational physicians
• Standard established testing for specific toxicants in situations where workers may receive significant exposures to these agents. For example, long-term exposure during cleanup of a polychlorinated biphenyls (PCB) waste facility can be monitored with pre-employment and periodic serum PCB testing.
  Standard procedures are available for determining levels of other substances, e.g., lead, cadmium, arsenic, and organophosphate pesticides.
  
• Where applicable, pre-employment blood specimens and serum was frozen for later testing. (PCBs and some pesticides are examples of agents amenable to such monitoring)

Sample Pre-Employment Examination

Occupational and Medical History

• Do a complete medical history emphasizing these systems: nervous, skin, lung, blood-forming, cardiovascular, gastrointestinal, genitourinary, reproductive, ear, nose, and throat.

Physical Examination

Include at least the following:

• Height, weight, temperature, pulse, respiration, and blood pressure.
  
• Head, nose, and throat.
  
• Eyes. Include vision tests that measure refraction, depth perception, and color vision. These tests should be administered by a qualified technician or physician. Vision quality is essential to safety, the accurate reading of instruments and labels, the avoidance of physical hazards, and for an appropriate response to color-coded labels and signals.
  
• Ears. Include audiometric tests, performed at 500, 1,000, 2,000, 3,000, 4,000, and 6,000 hertz (Hz) pure tone in an approved booth (see requirements listed in 29 CFR 1910.95, Appendix D). Tests should be administered by a qualified technician, and results read by a certified audiologist or a physician familiar with audiometric evaluation. The integrity of the eardrum should be established since perforated eardrums can provide a route of entry for chemicals into the body. The physician evaluating employees with perforated eardrums should consider the environmental conditions of the job and discuss possible specific safety controls with the Site Safety Officer, industrial hygienist, and/or other health professionals before deciding whether such individuals can safely work on site.
  
• Chest (heart and lungs).
  
• Peripheral vascular system.
  
• Abdomen and rectum including hernia exam).
  
• Spine and other components of the musculoskeletal system.
  
• Genitourinary system.
  
• Skin.
  
• Nervous system.

Tests

• Blood.
  
• Urine.
  
• A 14 x 17-inch posterior/anterior view chest X-ray, with lateral or oblique views, only if indicated or if mandated by state regulations. The X-ray should be taken by a certified radiology technician and interpreted by a board-certified or board-eligible radiologist. Chest X-rays taken in the last 12-month period, as well as the oldest chest X-ray available, should be obtained and used for comparison. Chest X-rays should not be repeated more than once a year unless otherwise determined by the examining physician.

Ability to Perform While Wearing Protective Equipment

To determine a worker’s capacity to perform when wearing protective equipment, additional tests may be necessary, for example:

• Pulmonary function testing. Measurement should include forced expiratory volume in 1 second (FEV), forced vital capacity (FVC), and FEV-to-FVC ratio, with interpretation and comparison to normal predicted values corrected for age, height, race, and sex. Other factors such as FEF, MEFR, MW, FRC, RV, and TLC may be included for additional information.

FEF = forced expiratory flow;
MEFR = maximal expiratory flow rate;
MW = maximal voluntary ventilation;
FRC = functional residual capacity;
RV = residual volume;
TLC = total lung capacity

A permanent record of flow curves should be placed in the worker’s medical records- The tests should be conducted by a certified technician and the results interpreted by a physician

• Electrocardiogram (EKG). At least one standard, 12-lead resting EKG should be performed at the discretion of the physician. A “stress test” (graded exercise) may be administered at the discretion of the examining physician. particularly where heat stress may occur.

Baseline Monitoring

If there is a likelihood of potential onsite exposure to a particular toxicant, specific baseline monitoring should be performed to establish data relating to that toxicant.

Periodic Medical Examinations

Periodic Screening

Periodic medical examinations should be developed and used in conjunction with pre-employment screening examinations. Comparison of sequential medical reports with baseline data is essential to determine biological trends that may mark early signs of adverse health effects, and thereby facilitate appropriate protective measures.
The frequency and content of examinations will vary, depending on the nature of the work and exposures. Generally. medical examinations have been recommended at least yearly. More frequent examinations may be necessary, depending on the extent of potential or actual exposure, the type of chemicals involved, the duration of the work assignment. and the individual worker’s profile. For example, workers participating in the cleanup of a PCB-contaminated building were initially examined monthly for serum PCB levels. A review of the data from the first few months revealed no appreciable evidence of PCB exposure. The frequency of PCB testing was then reduced. Periodic screening exams can include:

• Interval medical history. focusing on changes in health status, illnesses, and possible work-related symptoms. The examining physician should have information about the worker’s interval exposure history, including exposure monitoring at the job site, supplemented by worker-reported exposure history and general information on possible exposures at previously worked sites.
  
• Physical examination
  
• Additional medical testing, depending on available exposure information, medical history, end examination results.  Testing should be specific for the possible medical effects of the worker’s exposure. Multiple testing for a large range of potential exposures is not always useful; it may involve invasive procedures (e.g., tissue biopsy), be expensive, and may produce false-positive results.

Pulmonary function tests should be administered if the individual uses a respirator, has been or may be exposed to irritating or toxic substances, or if the individual has breathing difficulties, especially when wearing a respirator.

Audiometric tests. Annual retests are required for personnel subject to high noise exposures (an 8-hour, time-weighted average of 85 dBA’ or more), those required to wear hearing protection, or as otherwise indicated.

Vision tests. Annual retests are recommended to check for vision degradation.

Blood and urine tests when indicated.

Sample Periodic Medical Examination
The basic periodic medical examination is the same as the pre-employment screening (see the previous section).

Termination Examination

At the end of employment at a hazardous waste site, all personnel should have a medical examination as described in the previous sections (see Sample Pre-Employment Examination). This examination may be limited to obtaining an interval medical history of the period since the last full examination (consisting of medical history, physical examination, and laboratory tests) if all three following conditions are met:

• The last full medical examination was within the last 6 months.
• No exposure occurred since the last examination.
• No symptoms associated with exposure occurred since the last examination.

If any of these criteria are not met, a full examination is medically necessary at the termination of employment.