Who is allowed into the data centre: qualified electrician or layman?
Efficient access control is standard today in all data centres. Regardless of whether via pin code or key card – only authorised persons are allowed to enter. Authorised persons usually include all employees in the IT department and if necessary, Facility Management. Besides access control, an “Access to authorised personnel only” sign often indicates a special situation. Who is actually authorised, though?
As of February 2009, RCDs in final circuits have been a MUST in sockets up to 20A that are accessible to the layman. This is set out in DIN VDE 0100-410. However, RCDs are not particularly popular in data centre environments for two reasons:
these safety elements are very sensitive and just 15mA residual current may cause them to trip. They also have to be tripped manually every 6 months to check their proper function. Both unavoidably result in an interruption of the respective current path, which counts as a no-go in data centre environments.
Compulsory RCDs in final circuits for sockets up to 20A accessible to laymen is circumvented by many data centre operators who class employees who have access to the data centre as authorised or competent persons and not laymen. This is achieved in most cases by restricting access (access control) and affixing of “Access to authorised personnel only” signs.
The procedure described above is not only technically wrong, but also represents a financial risk for the company, management or owner in case of escalation. Depending on the extent of the damage or in case of personal injury, even prison sentences for the responsible persons cannot be excluded. Please therefore heed the following:
In line with the German Occupational Safety and Health Act (“Arbeitsschutzgesetz”: ArbSchG), the managing director(s) of a company must ensure that installations and equipment do not bear any risk for employees. If they are unable to assess this themselves from an electrotechnical point of view, they should appoint an electrical manager to assume all their duties. The appointed person must possess the appropriate training (foreman, technician etc.) and experience in the field of electrical installation and inspecting electrical installations. The electrical manager effectively assumes the obligations of the management for the company’s electrical installations and is personally liable for them. Standard duties of an electrical manager therefore include a risk assessment, regular employee training and a maintenance plan for the installations.
In large companies, additional electricians generally work under the electrical manager and assume practical duties under the latter’s supervision. These qualified electricians will have also completed electrotechnical training. They are generally intimate with the circumstances and requirements of the installations to be maintained and thus in data centres in particular, maximum availability
Secure IT operation naturally depends on many IT specialists, whose strengths lie in the area of network technology, high-level languages (C, C++, Java, SQL etc.) or hardware. However, from an electrotechnical point of view, these employees are classic laymen and actually should not have access to the data centre if RCDs are not installed. A remedy in this case are regular (annual) courses or instruction by a qualified electrician or electrical manager. During instruction a line is drawn between what is allowed and what not, and duties for maintaining function, and more importantly, personal protection, are defined. It is imperative that these training measures are documented as proof.
Autor: Tilo Püschel, © Bachmann GmbH 2018
