Safety Knights

Respiratory Protection Week - Day 2

Today is the 2nd day of Respiratory Protection Week. Each day this week, I will be posting various respiratory protection information, tips, and other relevant information to help ensure you keep your employees safe and healthy.

𝐃𝐚𝐲 𝟐: 𝐁𝐫𝐞𝐚𝐭𝐡𝐢𝐧𝐠 𝐀𝐢𝐫 𝐐𝐮𝐚𝐥𝐢𝐭𝐲
Atmosphere-supplying respirators (e.g., supplied-air and SCBAs) can be used in a wide variety of areas, including confined spaces, rescue teams, welding, abrasive blasting, and a number of other tasks. If you are using atmosphere-supplying respirators, OSHA requires that the breathing air be at least Grade D quality, as described in ANSI/CGA Commodity Specification for Air, G-7.1-1989. Grade D breathing air must meet the following specifications:
• Oxygen content (v/v) of 19.5-23.5%;
• Hydrocarbon (condensed) content of 5 milligrams per cubic meter of air or less;
• Carbon monoxide (CO) content of 10 ppm or less;
• Carbon dioxide (CO2) content of 1,000 ppm or less; and
• Lack of noticeable odor.

For compressors that are NOT oil-lubricated, you must ensure that CO levels in the breathing air do not exceed 10 ppm.

For oil-lubricated compressors, you must have either a high-temperature alarm and/or a CO alarm. If only high-temperature alarms are used, the air supply must be monitored at intervals sufficient to prevent CO in the breathing air from exceeding 10 ppm. This requirement is in place due to the compressor oil heating up (for a variety of reasons), therefore causing CO as a byproduct.

The CO alarms have to be calibrated periodically in accordance with the manufacturer's recommendations to ensure the sensor remains accurate and functions properly.

As a best practice and simple spot check, you can take a portable gas detector and place it inside the respirator for a minute or two (to allow for the sensor's T90 response time) and see what your readings are.