A CO Alarm Built for the Workplace
Carbon monoxide comes from fuel-burning equipment such as forklifts, heaters, generators and water heaters, and it has no color, odor or taste. Home CO alarms are built for the residential UL 2034 standard, which does not allow a reading to be displayed below 30 ppm. The Pro-Tech 8505 Commercial CO Alarm is designed for employers: it alarms based on the workplace exposure limits set by OSHA, NIOSH, ACGIH and Cal/OSHA, and it shows the CO level continuously from 9 ppm.
Why It Matters
Workplace CO limits are based on exposure over time, not a single reading. OSHA's limit is 50 ppm averaged over an 8-hour shift, and Cal/OSHA's is 25 ppm. Cal/OSHA has cited an employer after measuring 250 to 350 ppm inside an enclosed warehouse where employees had reported headaches and nausea for months.
How the Pro-Tech 8505 Alerts You
| CO Level |
Alarm Activates |
| 20 ppm |
Within 7 hours |
| 30 ppm |
Within 3 hours |
| 45 ppm |
Within 90 minutes |
| 90 ppm |
Within 15 minutes |
| 180 ppm |
At any time |
When an alarm activates, the red LED flashes and the 85 dB horn sounds four short beeps. These are the manufacturer's specified alarm points. Do not wait for an alarm if you suspect carbon monoxide exposure.
See What Happened While You Were Away
Press Display Memory to see the highest CO level detected, how long it lasted and how long ago it occurred. The 8505 keeps 30 days of peak history and calculates an 8-hour time-weighted average.
Simple to Install
It runs on one 9V alkaline battery, so there is no wiring and no electrician. Mount it on an interior wall about three inches above eye level, at least 5 feet from combustion or cooking appliances, and use one monitor for every 1,000 square feet of open space.
Good to Know
- For heated and air-conditioned commercial buildings, 40°F to 100°F
- Not for vehicles, unconditioned spaces or hazardous locations
- Not listed to UL 2034 and not intended to meet building or fire code CO alarm requirements
- Sensor life is 2 years; the manufacturer recommends replacing the monitor annually
- One-year limited manufacturer warranty; made in Canada
Download the owner's manual (PDF)