Mobile Phone Base Stations

Some notes for ringers

Introduction

The installation of mobile–phone equipment in the bell tower is a potentially valuable income source for a church and, once it has been installed, it will probably have little or no impact on the working of the church and will be virtually or completely invisible to the public. However, there could well be issues that affect the bell installation and the ringers, or cause them concern. The following issues are addressed below:

The design and installation work will be carried out by a specialist company (referred to from now on as “The Contractor”) on behalf of one or (most probably) several mobile–phone operators. They will carry out a survey, produce a design, provide draft PCC resolutions and facilitate the faculty application, produce a draft contract and carry out the installation. For the purposes of these notes, it is assumed that The Contractor will liaise with one or more designated points of contact within the church, referred to from now on as “The PCC” and “The Ringers”.

Planning and Monitoring

During the planning stages it is important for The Ringers to have someone (probably, but not necessarily, one of the local band) involved in liaising with The Contractor to discuss the issues outlined below. This includes examining the drawings, which will probably go through several iterations before they are finalised. It is important, and more straightforward, to ensure that all the required work is specified before the work starts, rather than to try to add work in during installation. The PCC will need to monitor the contract to ensure that it is satisfactory on other matters (e.g. finances, insurance, timescales etc.), but this is outside the scope of these notes.

Although The Contractor will have his own staff for overseeing the various tradesmen who will be employed in the installation work, it is a good idea for the overseer to have a point of contact amongst The Ringers. Great advantages can be gained for all parties if there is reasonably friendly contact, on a regular basis, between The Ringers and The Contractor’s overseer.

Size and Position of the Antennae

The attraction of churches for the phone–equipment operators is that the tower offers a convenient height for mounting the antennae (aerials). They are normally mounted behind the louvers in the tower and/or spire, and so are not visible from the ground. The existing louvers will probably be constructed from a material (e.g. slate, stone, heavy timber) which is opaque to the mobile–phone transmission signals, and so these will be removed and replaced by GRP louvers which match the originals in appearance but are transparent to the phone signals. If the antennae are to be mounted behind louvers in the bell chamber, The Ringers should seek reassurance that there is enough room, both during and after installation, taking into account such things as the bell frame, wheels, stays, and sound control.

Equipment Cabinets

Some of these will be quite large, and will occupy the equivalent of several 4-drawer filing cabinets. The total mass is likely to be a few hundred kilogrammes. They will also generate heat of the order of a few kilowatts, and may be fitted with ventilation fans that produce a low hum. The Ringers should satisfy themselves that the space these occupy, and the heat they produce, do not interfere with ringing or the bell installation. It is far from ideal to have these in the ringing chamber. If mounted in the bell chamber, consideration should be given to the possible effects of the heat generated, such as the drying–out and shrinkage of wooden bell frames and wheels. The Contractor should be able to give details of the heat that will be generated and the measures they will take to dissipate it. This might include thermostatically controlled forced ventilation or air conditioning, and should be specified during negotiations.

Smaller cabinets (RRUs – Remote Radio Units) may be sited close to each antenna to minimise signal loss, and, again, assurance should be sought that their size and the heat generated will not have any adverse effects on the bell installation or the ringers.

Access During and After Installation

After the installation is complete, The Contractor will want access for maintenance, probably at short notice. If suitable access is not present before they start, The Contractor will want to add or upgrade this as part of their installation work. There are regulations governing fixed ladders including the minimum distance from the wall and the requirements for safety hoops above a certain height. The Ringers and The PCC should ensure that the position of any new ladders does not interfere with the ringers, bells and ringing, and this must be done at the design stage. However, I know of a church where The Contractor accepted that there was no practical alternative to using a portable ladder for access from the ringing chamber to the bell chamber.

The Ringers and The PCC will need to understand how The Contractor will gain access during installation and how this will impact on ringing. Ringing will most probably have to be stopped during the installation, so its duration and timing will need to be agreed with The Contractor.

Possible Damage During Installation

If The Contractor needs to go through, or work in or near, the ringing chamber, the ringers would be sensible to ensure that the contents of the ringing chamber are protected or temporarily removed. The bell ropes should also be removed, both as a safety precaution, and to avoid their becoming dirty with masonry dust.

A considerable amount of masonry dust is likely to be produced during installation, so The Contractor should be required to protect vulnerable items before the work starts. This may include erecting a scaffolding “crash deck” above the bells, and wrapping up headstock bearings, rope pulleys, clock hammers, chiming hammers, etc. If there is a mechanical clock in the tower (a turret clock), it may need to be protected, together with the drive(s) to the clock face(s) and the gearing behind the face(s) for the hands. Electrical clocks will have an electrical slave unit and gearing behind each clock face. If there are chiming hammers that are mechanically operated via wires from the turret clock, then consideration should be given to whether these wires should be specially protected or temporarily removed. Should there be doubt about the vulnerability of the bell or clock installation, The PCC would be wise to require The Contractor to seek advice from one of the bell foundries, or a firm of bell hangers, or (for clock matters) a specialist clock firm. This could also be part of an arrangement for before and after inspections by the relevant specialist firms, with a contractual requirement on The Contractor to pay for any remedial work that becomes necessary. If work on the bells or clock is necessary to facilitate the installation, e.g. removal of bell wheels or chiming wires, The Contractor should be required to sub-contract this to a specialist firm as above. From a contractual viewpoint, it is probably not advisable for The Ringers to offer to do this work.

Health Concerns from Electro–Magnetic Radiation

Understandably, people will be concerned about health risks associated with the radiation from the antennae and this may be of particular concern to ringers, who will be closer to the antennae than the general public, and especially to anyone going into the bell chamber where they may be even closer. The Contractor will probably try to provide reassurance by stating that they work within the guidelines published by The International Commission on Non–Ionising Radiation Protection (ICNIRP). Although these are dated 1998, there is an ICNIRP statement from 2009 which “reconfirms the 1998 basic restrictions in the frequency range 100 kHz – 300 GHz until further notice”. This frequency range more than covers 3G and 4G mobile phones.

The guidelines quote reference levels for “general public exposure” in terms of the field strength for different frequency–bands, the principle being that the general public can include anyone and that they don’t need to worry about, or even know about, the fact that they are receiving the radiation. Higher field strengths are quoted for “occupational exposure” for “adults who are generally exposed under known conditions and are trained to be aware of potential risk and to take appropriate precautions”.

Now, ringers are not expected to be designers of this equipment, but it is useful to have the above information at the back of your mind. What I did (at St James, Islington) was to get The Contractor to quantify what would be the maximum field strength at each of their operating frequencies in the areas we were most concerned about (in our case, the bell chamber, where the antennae were to be sited). I also asked them to state whether these figures were within the “general public exposure” limits and, if not, to state what restrictions should apply to anyone going into those areas (e.g. to do bell maintenance). The Contractor showed some reluctance to be specific, but eventually committed themselves in writing to stating what the maximum levels would be (in W/m2). I checked these, and found they had calculated the figures in accordance with the ICNIRP Guidelines and that they were, in fact, the maxima quoted for general public exposure — yippee! So now these figures can be written into the contract, with a requirement for The Contractor to confirm that they comply with their own design figures when the job is finished. I recommend you do the same, and don’t let them fob you off with non–specific reassurances.

One more thing to be aware of is that the power output of the antennae will vary according to usage (how many people are using their phones at a particular moment), so the levels should be checked periodically. The Contractor’s standard contract will probably include a clause for this but it is worth checking.

Television Interference

People living close to mobile phone base stations may experience TV interference from 4G signals. There is more information about this here, and the problem can be resolved by fitting a filter, free of charge, between the aerial and the affected TV set. The Contractor installing the base station equipment may not mention this in advance but, for good public relations, it would be worth checking that he has notified local properties of the potential problem well before commissioning the equipment by sending out the appropriate postcard.


These notes have no official status but are based on my experience and are passed on here in the hope that they may be helpful. If you have any comments or think of something that might usefully be added, please .

Valid HTML 4.01 Transitional Peter Blight, June 2016
(last updated 24 September 2016)

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