S 1.72 Construction projects during ongoing operations

Initiation responsibility: IT Security Officer, Top Management

Implementation responsibility: IT Security Officer

For economic reasons, it is often advisable to expand the floor space available in the existing IT rooms by integrating adjacent rooms into them instead of building a new server room or computer centre. Expanding rooms in this manner often has a major impact on the existing building structure because new walls will need to be built or existing walls changed or removed. Furthermore, the additional space must be equipped with the corresponding infrastructure (raised floors, electrical power supply, air conditioning, security technology, etc.), which means a massive amount of work will need to be done here.

To ensure the business operations of the organisation are not disrupted, it is often necessary to continue operating the existing IT infrastructure during the construction work. At the same time, the ongoing IT operations should not restrict the construction work (if possible) or place requirements on the work so that the costs do not exceed the extent necessary.

Planning and preparatory changes to the infrastructure should be made first to ensure that the supporting technologies such as the power supply, air conditioning technology, and monitoring and alarming technology are not impaired by the construction work and remain operable. Subsequently, the affected area in which the IT is operated must be protected against contamination, but also against unauthorised access. At the same time, the construction site should not be obstructed unnecessarily. Proven measures for protecting against contamination include the following:

A plastic dust barrier should only be considered for short-term construction work that generates a minimum of dust. Heavy-duty plastic construction sheeting is attached to a wood stud construction for this purpose. The open joints between the barrier and neighbouring components as well as any holes in the plastic sheet (for inserting the necessary cables) should be taped over.

However, there is a risk when using this design that the protection provided against dust will be eliminated when the plastic sheet becomes damaged. Furthermore, it is not a secure barrier for people, which means additional safeguards are necessary to ensure no unauthorised persons can enter the construction area.

Simple plastic dust barriers (installed without a fixed stud construction) are often set up temporarily in order to build a gypsum board dust barrier in cases where it can be assumed that the drilling required will not generate too much dust.

In most cases, it is highly recommended to build a gypsum board dust barrier. Fastening just two layers of gypsum board to one side of the stud construction will provide adequate protection against dust. Using two layers prevents the area to be protected from being contaminated by fine dust particles that would otherwise easily be able to penetrate the joints between the sheets of gypsum board.

All areas in the existing construction in which work is performed as well as all unavoidable working joints should be sealed using an elastic sealing compound so that dust cannot penetrate at these locations either. Wall openings and cable feed-throughs should be avoided. If this is impossible, then such openings should be sealed using suitable sealing materials so that the highest possible protection against dust is guaranteed here as well.

It is generally possible to integrate doors into dust barriers, but such doors are a serious vulnerability in terms of protection against dust. The openings for the doors absolutely must be designed as airlocks to avoid drafts, and therefore the corresponding transportation of dust, in the IT rooms. In no way can an airlock constructed using two parallel sheets of plastic be considered adequate protection against dust.

If possible, airtight construction site doors should be installed. Large gaps in the construction site doors used can be sealed using rubber seals, for example.

Another advantage of this type of solid dust barrier is that the construction area is physically separated from the rooms in the computer centre because the construction workers will not have direct access to the computer centre after the gypsum board wall is constructed.

When performing construction work, experience has shown that it is best to create a constant underpressure in the construction area. To achieve this, a fan sucks the air out of the construction area and exhausts it to the outside through a closed system. As a result, it is guaranteed that a large portion of the dust created will be removed immediately and the remaining dust cannot get into the neighbouring areas. If there are any leaks, then the worst that can happen is that some of the dust-free air in the computer centre will be drawn into the construction area. One disadvantage of this safeguard is that it is necessary to create an exhaust opening in the façade to discharge the air.

If the construction work generates a lot of dust, then it is also recommended to use an air cleaner in the construction area. In this case, the air should be cleaned by a filter (referred to as a deduster). When cleaning the air using a water-based method, the air will be humidified up to its saturation point, which creates a "subtropical" working environment when the temperature is high and makes working more difficult.

Special work procedures such as the following could be required as additional safeguards for dust protection:

The client or the safety and health protection coordinator appointed by the client should check regularly if the applicable regulations, for example the occupational health and safety rules of the trade unions (e.g. BGR 217 "Handling mineral dust" or the technical rules for hazardous substances TRGS 500 "Protective measures: Minimum standards") are being complied with.

Upon completion of the construction work, a final cleanup of the construction site must be performed. If the final cleanup is not performed by the organisation's own employees, then this task must be stated explicitly in the request for tenders because it is beyond the scope of the construction cleanup to be performed by the contractor as defined in the VOB (construction tendering and contract regulations)

Example:

In addition to providing protection against dust, it is also necessary when performing construction work to ensure that the IT still in operation is adequately cooled. If air is used for cooling, then the additional dust generated by the construction work must be taken into account.

It is advisable to put corresponding instructions for all safeguards required in the tender specifications to avoid misunderstandings and expensive changes to the contract by the contractor.

Construction work does not only generate dust and noise, but can also cause damage to the existing technology due to carelessness or incorrect planning (for example when someone drills through a cable in the wall). In addition, large numbers of constantly changing external personnel will also usually be working simultaneously at many different locations. It must be ensured in this case that these personnel can be monitored adequately or that the IT areas are cordoned off from the construction areas in such a manner that unauthorised access is impossible.

Review questions:

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