Title
School of Medicine Nephropathology Laboratory: Formaldehyde/Xylene Safety
I. Principle
Formaldehyde and xylene vapor concentration must be maintained below the following maxima, expressed as parts per million, in all area of the Anatomic Pathology Department where formaldehyde or xylene are used.
Formaldehyde and xylene vapor concentrations must be monitored in all areas where these reagents are used. Initial monitoring involves identifying all employees who may be exposed at or above the action level or at or above the short-term exposure limit (STEL) and accurately determining the exposure of each employee identified. After the initial formaldehyde monitoring procedure, further periodic formaldehyde monitoring is mandated if results of the initial monitoring equals or exceeds 0.5 ppm (8-hour time-weighted exposure, the "action level") or 0.2 ppm (STEL). Initial monitoring must be repeated any time there is a change in production, equipment, process, personnel, or control measures which may result in new or additional exposure to formaldehyde for any employee involved in the activity.
The laboratory may discontinue periodic formaldehyde monitoring if:
- results from two (2) consecutive sampling periods taken at least seven (7) days apart show that employee exposure is below the action level limit and the short-term exposure limit; and
- no change has occurred in production, equipment, process, or personnel or control measures that may result in new or additional exposure to formaldehyde; and
- there have been no reports of conditions that may be associated with formaldehyde exposure.
If any personnel report signs or symptoms of respiratory or dermal conditions associated with formaldehyde exposure, the laboratory must promptly monitor the affected person's exposure.
Xylene must be monitored initially, but there is no requirement for periodic monitoring of xylene.
II. Action Limits
Action Limits for Exposure to Formaldehyde and Xylene
| |
8-hour Time-Weighted Exposure Limit |
Action Level (8-hour Time-Weighted Exposure) |
15-Minute Short-Term Average Exposure Limit (STEL) |
| Formaldehyde |
0.75 ppm |
0.5 ppm |
2.0 ppm |
| Xylene |
100 ppm |
|
150 ppm |
III. Records
Records of formalin/xylene monitoring have indicated that employees were not exposed to concentrations greater than the detection limit. On 02/27/2020, all employee's 15-minute and 8-hour formaldehyde readings were below the OSHA STEL recommendation (chart above). However, the 15-minute formaldehyde readings for all employees were over the NIOSH Recommended Expsosure Limit (REL) of 0.1 ppm. All results for xylene monitoring were below OSHA standards and NIOSH guidelines. Due to the formaldehyde results that were above the NIOSH REL, it was recommended that employees be monitored periodically. UNC Environment, Health & Safety (EHS) recommends that xylene monitoring only continues for new employees since the results are historically below the limits. All records are found in the Safety manual in room 408/412. Any records of corrective action when exposure limits are exceeded must be retained in the Safety Manual.
IV. Proper Handling
The proper PPE must be worn when handling formaldehyde (formalin) and xylene. This includes lab coat, gloves (8-mil or two 4-mil gloves), eye protection, and closed-toed shoes. Proper handling includes only working with these chemicals in a certified chemical fume hood with sash at or lower than recommended height. If in small quantities, such as patient vials, chemicals can be handled over an operational fume adsorber. When containers of said chemicals are moved, they must be closed/enclosed.
V. History
Created: 7/25/12 LHR
Replaces: N/A
Revisions:
- 5/28/20 KDB
- LEC 2/11/20
- 7/2/18 LHR
- 6/29/16