thePetroStreet

Can any one explain me the followings

1- Hazardous electrical area classification.On which basis specfic area of plant should be classified and where this classification applied?
2- What is meant by NEMA 4 or 4X rating?
3- How lighting illumination measured? What is the best software available for illumination measurement and please explain its basic operation.

Hi,

Please see attachments....

Regards,
Sameen

Here is a good guide for understanding forms of separation.

Lighting Illumination is usually measured in Lux (unit). Lighting studies are carried out before setup of a facility to ensure adequate illumination at working plane of employees and also depending on whether its manned or not. Common softwares used for this purpose are Calculux (Old) and DialLux (New). You can download these softwares along with their luminary & fixtures libraries from the philips website.

As far as standards are concerned, there are standards for this as well which provide guidelines as to what fixtures/luminary should be used in a particular application and what lux level should be maintained at a particular working plane. Examples is EXXON BP 16-5-1 for lighting.