What Does Rainbow Passage Mean?
The Rainbow Passage is a short passage that can be read out loud as part of a respirator fit test.
Respirators will only provide their intended level of protection if they form a sturdy, unbroken seal on the wearer's face. Completing a respirator fit test ensures that this seal is complete and won't be broken by the user's facial movements or work activities.
If the respirator's seal fails during any of these tests, including the reading of the Rainbow Passage, the respirator must be resized or substituted for one that has the right fit.
Safeopedia Explains Rainbow Passage
Respirators are a critical type of personal protective equipment (PPE) for various types of work.
Respirators protect workers in two basic ways:
- Filtering contaminants from the air so the user can breathe comfortably without being exposed to harmful airborne substances like fumes and chemicals
- Supplying the user with clean, breathable air so they can safely work in oxygen-deficient atmospheres or in spaces with extremely harmful airborne substances
As stated above, however, these respirators will not provide adequate protection unless they pass a fit test for each user.
The Text of the Rainbow Passage
The Rainbow Passage reads:
When the sunlight strikes raindrops in the air, they act as a prism and form a rainbow. The rainbow is a division of white light into many beautiful colors. These take the shape of a long round arch, with its path high above, and its two ends apparently beyond the horizon. There is, according to legend, a boiling pot of gold at one end. People look, but no one ever finds it. When a man looks for something beyond reach, his friends say he is looking for the pot of gold at the end of the rainbow.
Why Fit Tests Use the Rainbow Passage
The Rainbow Passage is not technically required for a respirator fit test. The user simply has to speak for one minute to complete the test. The Rainbow Passage is a convenient passage that the user can recite to complete this portion of the test.
The passage has its origins in speech therapy as a tool to assess the vocal abilities of patients and clients. The passage is short and phonetically balanced, meaning the reader quickly makes use of a variety of sounds and mouth movements that reflect those used in unscripted English speech.
This range of mouth movements is what makes the Rainbow Passage particularly well suited for fit testing. If speaking while wearing the respirator would break the seal, reciting this passage allows the tester to catch this before sending the user to work.
The Respirator Fit Testing Exercises
For both qualitative fit testing (QLFT) and quantitative fit testing (QNFT), the user must wear the PPE (like earmuffs or safety glasses) and prescription eyewear they would be using on the job. Once these and the respirator are on, the user will then perform the following test exercises:
- Normal breathing
- Deep breathing
- Turning head side to side
- Moving head up and down
- Talking (or reading the Rainbow Passage)
- Bending over
- Normal breathing
Fit testing procedures must conform to the Occupational Safety and Health Administration’s (OSHA) 1910.134 App A - Fit Testing Procedures (Mandatory). Appendix A.