The sound level meters and noise dosemeters that Cirrus manufactures are designed to meet the performance criteria laid down in various standards.

For example, the optimus sound level meters are designed to meet the requirements of BS EN 61672-1:2003 which isalso known as IEC 61672-1:2002。

Within these standards there are many different performance criteria that the instrument must meet along with tolerances that are allowed. It may not be possible for the instrument to meet the exact requirements all of these criteria but as long as it is within the tolerances that is acceptable.

The older standards for sound level meters had different levels of tolerances with the tightest known as Type 0, with Type 1, Type 2 and Type 3 progressively looser in terms of the tolerances allowed. It is generally easier to make a measurement instrument meet wider tolerances and this is usually reflected in the price. A Type 1 sound level meter would usually have been more expensive than the equivalent Type 2 version.

Type 0 was often only used for very accurate laboratory standard instruments whereas Type 3 was considered potentially too inaccurate for use in any situation where measurements may need to be repeated.

For example, the 1989 Noise at Work Regulations specified that sound level meters should have met Type 2 or Type 1 of BS EN 60804.

当开发了声音水平仪的新标准IEC 61672时，类型被类替换为类别，0和3的水平被删除（IEC 61672-1：2002取代了先前的标准IEC 60651和IEC 60804，这些标准已被撤回）。

When the 2005 Control of Noise at Work Regulations were introduced, this new standard was introduced as the preferred option and so the requirement now reads:

“声级计至少应该满足类2 of BS EN 61672-1:2003 (the current instrumentation standard for sound level meters), or at least Type 2 of BS EN 60804:2001 (the former standard)“.

In terms of accuracy, a Class 2 and Type 2 instrument are roughly equivalent and a Class 1 and Type 1 instrument are also roughly equivalent although there are technical differences in the standards. An instrument that was designed to meet the older standards may not be able of meeting the requirements of the new standard.

For more information, please call us on 0845 230 2434 in the UK or use the contact form on the right to send us an email.

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Clarke Roberts

Senior Marketing ExecutiveatBOB体育登陆入口

Clarke is a Senior Marketing Executive and is responsible for helping people to find Cirrus Research's innovative noise measurement solutions by using all aspects of the marketing mix.

He particularly enjoys writing content about product applications, including noise nuisance, occupational noise and environmental noise pollution.

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