Before revision: These devices measure low levels of CO immediately, without the intentional minutes or hours delay of alarm devices designed only to sound in hazard conditions, without false alarms due to non-dangerous concentrations .
After revision: (alarms with concentration readout may also display without delay, but are less sensitive)These devices measure low levels of CO immediately, without the intentional minutes or hours delay of alarm devices designed only to sound in hazard conditions, without false alarms due to non-dangerous concentrations .