Strongarm offers the widest range of hazardous safety options available for use in systems subject to the presence of potentially explosive gases, liquids, or powders.

We offer multiple agency-approved systems and safety assurance not available with do-it-yourself systems. Strongarm provides the most current safety strategies for the best protection of people and processes. Our custom engineered and built permit you to strategically place an easily accessible operator interface system anywhere in your environment in accordance with safety requirements.

Strongarm has the expertise and experience to customize, design, and build the ideal operator interface to suit your application. Our extensive design resources enable us to engineer every feature you’ll need before in-house fabrication, assembly, finishing, testing, quality assurance, and on-time delivery. Since 1990, we’ve designed, built, and delivered over 500,000 products on time for our customers.

In North America, hazardous locations have traditionally been defined by a combination of classes and divisions as follows:

Classes

Class I – A location made hazardous by the presence of flammable gases or vapors that may be present in the air in quantities sufficient to produce an explosive or ignitable mixture.

Class II – A location made hazardous by the presence of combustible or electrically conductive dust.

Class III – A location made hazardous by the presence of easily ignitable fibers or flyings in the air, but not likely to be in suspension in quantities sufficient to produce ignitable mixtures.

Divisions

Division 1 – A location where a classified hazard exists or is likely to exist under normal conditions.

Division 2 – A location where a classified hazard does not normally exist but is possible to appear under abnormal conditions.

The Zone System

The U.S. and Canada have recently revised installation codes to recognize an international 3-Zone area classification system for equipment used in hazardous locations.

Zone 0 – An area in which an explosive gas atmosphere is continuously present for a long period of time.

Zone 1 – An area in which an explosive atmosphere is likely to occur in normal operation.

Zone 2 – An area in which an explosive gas atmosphere does not normally exist.
In Canada, all new installations must use the 3-Zone system. Existing installations may continue to use the 2-Division system or opt to re-classify using the 3-Zone system.

In the U.S., all installations (both new and existing) can either continue using the 2-Division system or re-classify their product using the 3-Zone system.

Pressurization Systems

Type X
For Class I, Division 1 (or Zone 1) locations, you must use a Type X purging system. Type X purging systems reduce the hazards from Division I (or Zone 1) to unclassified. You must cut power off immediately when the positive-pressure air system fails. You also must detect failure of the system at the discharge end of the fan.

Type Z
Type Z purging systems reduce the classification from Division 2 (Zone 2) to unclassified. If the control room location and/or equipment is suitable for these type of purges, then it’s not necessary to de-energize the power supply circuit to the control room equipment immediately upon a positive pressure air system failure. However, for safety’s sake, you should de-energize that equipment as soon as possible after you detect air failure, or that some means of monitoring the atmosphere within the room be started.

Non-Incendive System

Defined as systems having electrical/electronic circuitry that is incapable, under normal operating conditions, of causing ignition of a specified flammable gas-air, vapor-air, or dust-air mixture due to arcing or thermal means.

Approvals available:
Class I Division 2 up to Division 1
Class II Division 2 up to Division 1
Groups A, B, C, D