EXPLOSION-PROOF HOISTS FOR CLASSIFIED AREAS
- sclaferriere
- Oct 30
- 2 min read
Context: What do we mean by "exproof"?
To fully understand the benefit of an "ex-proof" hoist, we need to go back to the concepts of classifying places at risk of explosion.
Potentially explosive atmospheres are classified according to Classes , Divisions (or Zones according to the IEC/NEC standard) and Gas/Vapor Groups .
For example, Class I concerns flammable gases or vapors. A Division 1 means that an explosive atmosphere may be present under normal operating conditions , while Division 2 means that the atmosphere is considered "abnormal" (e.g., may appear during malfunctions).
The term "ex-proof" (or explosion-proof) therefore refers to equipment designed to operate safely in these atmospheres, with appropriate electrical, mechanical and thermal protections: shielded wiring, sealed boxes, non-sparkling components (bronze wheels, stainless steel cables, etc.).
At Protech, we have several brands of hoists available for classified areas.
For smaller capacities, manual hoists and trolleys are available. (ATEX)
-Bronze-coated wheels specially designed to resist sparks.
-Load hooks designed to resist sparks at the point of contact.
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For medium capacities (1T to 5T), there are exproof chain hoists;
GAS: Class I, Division 1
GAS: Class I, Division 2
DUST: Class II, Division 1
DUST: Class II, Division 2
R&M Exproof Wire Rope Hoists for Large Capacity
Different versions – Div 2 vs Div 1
The Spacemaster EX range covers at least two major hazard classes:
Class I, Division 2 (Div 2) for Groups B, C, D and temperature T3.
Class I, Division 1 (Div 1) for Groups C & D and temperature T4.
The Div 1 version is designed for more severe environments (explosive atmosphere present more frequently or continuously) than the Div 2.
Main capabilities and technical characteristics
Non-sparking options and components suitable for explosive environments, e.g., bronze-coated hooks, brass wheels, stainless steel cable, etc. rmhoist.com
