Fixed Point Gas Detection

A breath of compressed air

Many industrial facilities need breathing air to protect workers from hazardous airborne contaminants. Often, general plant compressed air is used as a source. However, the conditions at the air compressor’s intake can’t be guaranteed. Purifiers are needed to clean and condition the air to ensure it meets required breathing air standards. Purifiers using fixed-cycle heatless desiccant dryers might use significant amounts of expensive compressed air for purging. This purge flow usually is higher than required because breathing air systems are subject to inlet flow rates that are less than the purifier rating point. Let’s explore the effects of purge flow in breathing air purifiers and discuss measures that reduce purge flow and save operating costs.

The environment around a paint booth or cleanroom might be clean, dry and free of vapors, but there’s no guarantee these same conditions exist at the intake of the compressor that provides breathing air. “We’ve been using breathing air filters to condition our air for our welding hoods”, says the welding supervisor at a highway coach manufacturer. “But we make vehicles, so, despite warning signs posted around our compressor rooms, very often idling vehicles cause our carbon monoxide alarms to ring regularly.” Contaminants that could affect the health of breathing air users include oil aerosols, oil vapors, solid particles, carbon monoxide and microorganisms.

Compressed air for breathing air applications must be purified properly to ensure that it meets the relevant local breathing air standards. Standards exist in most every country and dictate the protection required for workers exposed to hazardous environments. One example is the use of breathing hoods or masks. The compressed air sent to these devices must meet breathing air quality criteria, as determined by OSHA in the United States and CSA in Canada. These standards define acceptable levels of oxygen, nitrogen, carbon dioxide, carbon monoxide, moisture and other trace gases.

Often desiccant-style breathing air purifiers are used to help condition the air to meet the required standards. These units (Figure 1) typically contain a filtration system, a desiccant air dryer and a catalyst element. The filtration system removes particles, liquid aerosols, oil vapors and odors that might be transmitted from the air compressor intake, through the distribution system to the worker. The catalyst converts carbon monoxide that might be present to more tolerable carbon dioxide. The desiccant dryer removes the water vapor so the catalyst can operate without contamination, as these are sensitive to the presence of water vapor.

AutomatedBuildings.com Press Releases - New Products

FieldServer Technologies, a leading developer of building  automation interface protocol gateways, announced the release of the Point Six Wireless Gateway,  Point Six Wireless manufactures a variety of unique, high value wireless solutions for commercial and industrial OEMs.  The FieldServer Technologies Gateway solution enables these devices to easily interface with current open building automation protocols including BACnet, LonWorks, Metasys N2 by JCI, Modbus and SNMP.  Users can now take advantage of the wide variety of Point Six environmental sensors and be assured that the data is compatible with standard Building Automation protocols making it easy to interface with building and campus management systems.  The FieldServer gateway supports the complete line of Point Six Wi-Fi, 900MHz and 418/433 MHz sensors spanning from environment sensors to voltage, current and digital sensors. 
The ZG-JSL linkage simplifies typical installations and eliminates the difficulties where jackshaft bearings are hard to access. By improving the method of installing actuators onto jackshafts, the installer saves on installation time translating into a cost savings. The quicker the install, the sooner the installer can move on to the next project. Now with the ZG-JSL linkage all jackshaft installations will only take minutes!   The Innotech® innSIGHT Supervisor Web Server allows easy access to user selected information from controllers connected to the Innotech Net Comms network through the embedded web server. The information selected can be accessed with Internet Explorer® version 8 or above web browser, and is as simple as browsing a typical web site. It allows you to view and modify accessible point values, without being immersed in the technical details of the configuration.  Features - 2 x Isolated RS485 Net Comms Network ports (PC and NET)• 1 x Isolated Ethernet (10baseT) port• User selectable Baud rate on RS485 Net Comms Network ports• All wires connected by pluggable  screw terminals• Program resides in non-volatile flash RAM• Real-Time Clock (battery backed)• Visual indication of power, system, and communication activity• Embedded web server• With its comprehensive range of butterfly valves, Belimo offers integrated and cost effective solutions for controlling medium to high flows.

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Continuous monitoring for hazardous material releases

Safety and health in confined spaces

Prevention and Control of Accidental Releases of Hazardous Gases

The Gas Monitoring Handbook