Step 1: | Identify all employees who have potential exposure to airborne formaldehyde in your workplace. |
Step 2: | Identify operations where employee exposures could exceed the 15-minute short-term exposure limit (STEL) for formaldehyde of 2 parts per million (ppm). |
Note: | You may use monitoring devices such as colorimetric indicator tubes or real-time monitors to screen for activities where employee exposures could exceed the STEL. |
Step 3: | Select employees from those working in the operations you identified in Step 2 who will have their 15-minute exposures monitored. |
Step 4: | Select employees from those identified in Step 1 who will have their 8-hour exposures monitored. |
– Make sure the exposures of the employees selected represent 8-hour exposures for all employees identified in Step 1, including each job activity, work area, and shift. | |
■ If you expect exposures to be below the action level (AL), you may limit your selection to those employees reasonably believed to have the highest exposures. | |
■ If you find any of those employees' exposure to be above the AL, then you need to repeat monitoring to include each job activity, work area, and shift. |
Reference: | A written description of the procedure used for obtaining representative employee exposure monitoring results needs to be kept as part of your exposure records, as required by Exposure records, WAC 296-856-20070. |
– This description can be created while completing Steps 3 through 6 of this exposure evaluation process. | |
Step 5: | Determine how you will obtain accurate employee exposure monitoring results. Select and use an air monitoring method with a confidence level of 95 percent, that is accurate to: |
– ±25 percent when concentrations are potentially above the TWA of 0.75 parts per million (ppm). | |
– ±25 percent when concentrations are potentially above the STEL of 2 ppm. | |
– ±35 percent when concentrations are potentially above the AL. |
Note: | • Here are examples of air monitoring methods that meet this accuracy requirement: |
– OSHA Method 52 found at http://www.osha.gov/dts/sltc/methods/toc.html. | |
– NIOSH methods: 2016, 2514, 3500, 2539, and 5700, found at http://www.cdc.gov/niosh/homepage.html and linking to the NIOSH Manual of Analytical Methods. | |
– Direct reading methods found at http://www.osha.gov/SLTC/formaldehyde/index.html |
Step 6: | Obtain employee exposure monitoring results by collecting air samples to accurately determine the formaldehyde exposure of employees identified in Steps 3 and 4. |
– Make sure samples are collected from each selected employee's breathing zone. |
Note: | • You may use any sampling method that meets the accuracy specified in Step 5. Examples of these methods include: |
– Real-time monitors that provide immediate exposure monitoring results. | |
– Equipment that collects samples that are sent to a laboratory for analysis. | |
• The following are examples of methods for collecting samples representative of 8-hour exposures. | |
– Collect one or more continuous samples, such as a single 8-hour sample or four 2-hour samples. | |
– Take a minimum of 5 brief samples, such as five 15-minute samples, during the work shift at randomly selected times. | |
• For work shifts longer than 8 hours, monitor the continuous 8-hour portion of the shift expected to have the highest average exposure concentration. |
Step 7: | Have the samples you collected analyzed to obtain employee exposure monitoring results for 8-hour and short-term exposure limits (STEL) exposures. |
– Determine if employee exposure monitoring results are above or below the following values: | |
■ 8-hour action level (AL) of 0.5 ppm. | |
■ 8-hour time-weighted average (TWA8) of 0.75 ppm. | |
■ 15-minute short-term exposure limit (STEL) of 2 ppm. |
Reference: | To use the monitoring results to determine which additional chapter sections apply to employee exposure in your workplace, turn to the Scope, WAC 296-856-100, and follow Table 1 in that section. |
Note: | • You may contact your local WISHA consultant for help with: |
– Interpreting data or other information. | |
– Determining 8-hour employee exposure monitoring results. | |
• To contact a WISHA consultant: | |
– Go to the safety and health core rules, chapter 296-800 WAC; and | |
– Find the resources section, and under "other resources," find service locations for labor and industries. |