Answering your questions

Sept. 1, 2010

Eyewash station requirements

Q Do labs need to have a continuous-flow eyewash station? We have an eyewash station in our hospital laboratory that houses a 32-oz. bottle of “eye saline” and directions for use. Does this meet regulatory requirements?

A The Occupational Safety and Health Administration's (OSHA) requirements for eyewash stations in the laboratory are rather general. “Where the eyes or body of any person may be exposed to injurious corrosive materials, suitable facilities for quick drenching or flushing of the eyes and body shall be provided within the work area for immediate emergency use.”1 An interpretative letter from OSHA says, “As you may know, 29 CFR 1910.151(c) does not provide specific instruction regarding the installation and operation of emergency eyewash and shower equipment. Therefore, it is the employer's responsibility to assess the particular conditions related to the eyewash/shower unit, such as water temperature, to ensure that the eyewash/shower unit provides suitable protection against caustic chemicals/materials to which employees may be exposed.2

The College of American Pathologists (CAP) is more specific in its accreditation requirements:

1. Emergency eyewash stations should be located within 100 feet or 10-seconds travel distance from every area of the laboratory in which hazardous chemicals (irritating, corrosive, or toxic by contact or absorption) or biohazards are present.

2. The eyewash solution may use sterile saline, an antiseptic ophthalmic solution within date, or fresh running tap water.

3. The wash solution must be free of contaminants.

4. If there is a plumbed system, it must be activated weekly to verify proper operation.

5. Manufacturer instructions must be followed for commercial bottled eyewash products.3

All of the regulatory agencies refer to recommendations of American National Standards Institute (ANSI). Emergency eyewash and shower equipment. ANSI document Z358.1-1998 contains has the following recommendations:

1. Plumbed and self-contained eyewash equipment (plumbed eyewash; nonpressurized self-contained eyewash; pressurized self-contained eyewash) should be capable of delivering flushing fluid to the eyes not less than 1.5 liters per minute (0.4 gpm) for 15 minutes.

2. Eye/face wash equipment (plumbed) should be capable of delivering flushing fluid to the eyes not less than 11.4 liters per minute (3.0 gpm) for 15 minutes.

3. Flushing fluid is defined as: potable water, preserved water, preserved buffered saline solution, or other medically acceptable solution manufactured and labeled in accordance with applicable government regulations.4

These CAP and ANSI recommendations are not enforced by OSHA.

—Brad S. Karon, MD, PhD
on behalf of Daniel M. Baer, MD, deceased


  1. Occupational Safety and Health Administration. OSHA. 63 FR 33450, 1910.151(c). Accessed August 12, 2010.
  2. Occupational Safety and Health Administration. Standard Interpretations 04/18/2002 – ANSI Z358.1 guidance for complying with 1910.151(c) citation policy for eyewashes and showers. Accessed July 14, 2010.
  3. College of American Pathologists. CAP Laboratory Accreditation Program, Laboratory General Checklist question GEN.72500 commentary, 2007.
  4. American National Standards Institute. ANSI standard Z358.1-1990, American National Standards Institute Inc. New York

Biosafety hoods for small labs

Q We are exposed to noxious fumes daily from stool samples and 24-hour urine samples routinely processed in our very small lab and dumped down the sink. We have no biosafety hood/cabinet. Are there regulatory standards defined for required biosafety hood/cabinet use in medical labs?

A The work described constitutes BSL-2. This is the designation used for work done in clinical facilities by the Centers for Disease Control and Prevention (CDC) and the National Institutes of Health (NIH). BSL-2 primary barriers include the following: Class I or Class II biological safety cabinets or other physical containment devices used for all manipulations of agents that cause splashes or aerosols of infectious materials; lab coats, gloves, and face protection as needed.

Lab coats and gowns are used to protect workers from hazardous materials. They can also provide protection for the material or product from contamination by the worker. In BSL-2 laboratories, open-front lab coats are acceptable. The OHSA bloodborne pathogen standard (OSHA, 1991) states that gloves are mandatory for handling human blood or body fluids.

Hand washing after glove removal is essential. Eye and face protection is recommended if working with infectious substances that may cause a splash, which might be the case when disposing of 24-hour urine specimens.

Personal protective equipment (PPE) must be worn and used appropriately to form effective barriers. Biosafety hoods are not required for use in BSL-2 facilities, but appropriate PPE is necessary. Both the CDC and NIH have information on these regulatory standards.

—Susan E. Sharp, PhD, D(ABMM)
Director of Microbiology
Kaiser Permanente – NW
Portland, OR

Further reading

  1. Fleming D, Hunt D, eds. Biological Safety Principles and Practices. 3rd ed. Washington, DC: ASM Press; 2000.

Albumin levels with renal disease

Q Is it possible for someone with stage-4 chronic renal disease and congestive heart failure to have an albumin less than 1 g/dL? Our analytical range is 1 g/dL to 6 g/dL and the normal range is 3.4 g/dL to 4.8 g/dL.

A Patients with severe nephrotic syndrome, on rare occasions, may present with an albumin level less than 1 g/dL. In our institution this has occurred (very rarely) in patients with severe renal disease such as renal amyloidosis and focal-segmental glomerulosclerosis.

The second question would be whether there is any value in reporting a number in these patients as opposed to “less than 1 mg/dL.” The answer to that question would depend upon the analytical performance of your assay (i.e., is it linear to levels below 1 g/dL?), and the needs of the clinicians in your institution. Providing a discrete number (0.7 g/dL) probably tells the clinician little more than providing a result of “less than 1 g/dL,” so it may not be worth validating your analytical measurement range down below 1 g/dL for these rare occasions. These are, however, discussions that should take place between the laboratory and the medical staff it serves.

—Brad S. Karon, MD, PhD

Thawing frozen specimens

Q There is plenty of information on how to freeze specimens, but I cannot find any information on how to thaw them. Is there a general rule for thawing frozen specimens?

A You are right that there is no shortage of literature on how and when to freeze a specimen, but thawing instructions are a little harder to find. In part, I suspect this is due the relative simplicity of the process. For most analytes, thaw specimens at room temperature and mix by inversion before testing. Thawing in a 37^0C water bath or heat block may be acceptable unless the specimens are thermolabile. When such specimens are neglected and allowed to stay at warm temperatures, heat sensitive analytes may deteriorate and render inaccurate results.1

—Dennis J. Ernst, MT(ASCP)
Center for Phlebotomy Education
Corydon, IN


  1. CLSI. Collection, Transport, and Processing of Blood Specimens for Testing Plasma-Based Coagulation Assays and Molecular Hemostasis Assays; Approved Guideline—Fourth Edition. CLSI document H21-A5. Wayne, PA: Clinical and Laboratory Standards Institute; 2008.

Brad S. Karon, MD, PhD, is associate professor of laboratory medicine and pathology, and director of the Hospital Clinical Laboratories, point-of-care testing, and phlebotomy services at Mayo Clinic in Rochester, MN.

MLO's “Tips from the Clinical Experts” provides practical, up-to-date solutions to readers' technical and clinical issues from a panel of experts in various fields. Readers may send questions to Brad S. Karon, MD, PhD, by e-mail at [email protected].