Few users plan to alter hazardous zone designations

Natick, MA—Only a few users and operators expect to change their applications' hazardous area zone classifications during 2003-06, according to a recent study by Venture Development Corp. (VDC).

By Control Engineering Staff May 14, 2003

Natick, MA Only a few users and operators expect to change their applications’ hazardous area zone classifications during 2003-06, according to a recent study, ”European and North American Markets For Intrinsically Safe Equipment,” by Venture Development Corp. (VDC). This inertia will likely delay any worldwide harmonization of hazardous area designations, equipment standards, and certification/approval requirements.

Present and Projected Hazardous Area Categorizationsin North America (in applications where intrinsically safe equipment is used)

(% of hazardous regionsidentified by users)

Present (2003)
Projected (2006)

Zones 0, 1, 2

Division 1

Division 2

Source: Control Engineering with data from Venture Development Corp. (Natick, MA) at www.vdc-corp.com

Among all classes of users, the study found that firms with production facilities in both Europe and North America will likely be early adopters of a common classification standard because a common certification procedures would reduce costs and time needed for certifications. Vendors of equipment used in intrinsically safe applications also see the advantage of reducing certification costs with one standard, while some see reduced product development costs.

However, among vendors of products used in intrinsically safe applications, who were asked about the likelihood of a worldwide hazardous region classification standard,, the median response was that it could happen in 10 years, though some thought it could occur in five years, while others expect it will never happen.

Views also differ among those that expect a common standard to evolve. Some expect that European standards will be chosen, while others expect harmonization to consist of an amalgamation of the best of the worldwide standards, such as NEC and IEC standards. The vendors reported that hindrances to adoption include:

Contrary to interests of regional certifying agencies;

Differences between classification schemes of Europe and North America are large;

No compelling reason for end-users to change;

North American end-users do not understand zone categorizations;

Retraining of personnel too expensive; and

Too costly for users in converting.

Hazardous regions are areas where there can be ignitable or explosive atmospheres, such as gas-air mixtures, and certain dusts. Means must be provided to prevent equipment used in these regions from causing ignitions or explosions. Intrinsic safety is a method used extensively in Europe for this purpose. It also is gaining favor in North America.

A region that is designated as Zone 0, Zone 20, Zone 1, or Zone 21 in the European system can be considered an equivalent to Division 1 in the North American classification system, while a region designated as Zone 2, or Zone 22, can be considered equivalent to a Division 2 designation in North America.

VDC reports that in Canada and the U.S. efforts have been made to change codes and standards to allow use of the zone classification system for new installations and for reclassifying existing facilities. However, it adds that getting users to apply these reclassifications will not be easy.

Control Engineering Daily News DeskJim Montague, news editor jmontague@reedbusiness.com