In-house monitoring devices

When are the monitoring devices being installed?

The monitors have now arrived in the UK and will be delivered to the Council Offices on Wednesday 4 December. Installation will commence on Thursday 5 December and is expected to be completed by Friday 6 December.

How are the monitoring devices being installed?

The devices are simply plugged into the nearest electrical socket—no invasive work will be carried out in your home.

Where are the monitoring devices being placed?

Placement is based on assessments conducted in your home, typically near service ducts for optimal functionality.

What if there isn’t a plug nearby?

If no nearby socket is available, we will provide an extension lead as a temporary solution to power the device.

Can the devices be moved?

The devices will be positioned according to the results of a Risk Assessment to ensure they operate effectively. We recommend avoiding moving them far from this designated spot.

Do the devices need to be permanently plugged in?

The base of device needs to remain plugged in to ensure full battery on your device.

What work will be done to my property during installation?

No drilling or permanent alterations will be carried out. The device will simply be plugged in. A wall bracket will be left behind should you wish to install it yourself later.

Why aren’t you offering appointments for installation?

Please avoid visiting your home during the installation period (5–6 December) to maximise the efficiency of Rockall Safety Engineers. To complete all installations efficiently across two days, we are unable to allocate individual time slots. Our team will work as quickly as possible, aiming to install devices into roughly 20 homes on each day. Offering appointments would reduce the likelihood of completing all installations within this timeframe. The police will be in attendance when any properties are entered without the presence of the home owner.

What if I don’t want the installation now?

Rockall, the installation team, is only available on 5 and 6 December. If the installation doesn’t take place during this time, you will need to wait until the new year for the next available dates.

What if I don’t feel comfortable leaving my keys?

If you are uncomfortable leaving your keys, we may ask you to wait while the installation is completed. Please note, we can only provide a general timeframe, not a specific appointment.

What happens after the installation?

An email confirmation will be sent as soon as installation is complete in your home. Further details about the online portal and alarm response process will follow shortly.

Am I responsible for the maintenance of the monitoring device? 

The provision of monitors has been recommended by the Local Resilience Forum. You would not be responsible for maintenance whilst that advice remains in place.

What happens if the alarm activates?

If an alarm is triggered, a call handler will contact you through the device to give you instructions. If you are not in the house at the time that the alarm activates you will contacted on the emergency numbers that you have provided. This is part of a multi-agency protocol which has been informed by the Risk Assessments.  Further details about what to expect will be provided to you in advance to ensure you are well-prepared.

Do I need to sign for anything?

No, there is no need to sign any documentation during the installation process. We only require your consent to proceed with the installation and share your contact details with the service provider.

When can I see my risk assessment? 

The Risk Assessment templates were all populated last week (25/11/24). As of Monday 2 December, they have been shared with an independent assessor. As we move forward, we will be offering discussions with individual household, where if you would like to see your risk assessment this can be arranged. 

One of our neighbours has said that the residents will need to pay for any on going monitoring that is required in our homes after a year. Is this correct? 

The Council has made a commitment to fund the in house monitors for 12 months based upon advice from the technical cell. A commitment beyond 12 months would be based upon the outcomes of all forms of monitoring in that period.
 

(Taken from technical report produced by EPG and approved by the Bedfordshire Local Resilience Forum Technical Cell)

The activation of the G7c device in the hallway of 11 Wagstaffe Close was not caused by methane emissions from the ground. This is based on the evidence provided by agencies that attended the activation, subsequent tests undertaken by Blackline Safety, and the following risk assessment:

• The data from the Blackline device shows that the flammable gas which activated the alarm was not methane. It was a heavier compound such as octane, an aromatic hydrocarbon, or other compound with a molecular weight greater than 80g/mol. The device has been checked at Blackline and the device is working correctly.
• An air freshener was plugged in, very close to and above the device. Some of the group of gases that could have activated the LEL alarm are common in air fresheners. The heavy gas it detected will also be heavier than air so if present in the air freshener it would sink towards the device. However, it is understood from the resident that the air freshener has been in place since the device was installed. It is not clear what temperature, or other variations, could have changed the concentration of gas reaching the device. The safety data sheet indicates it contains heavy volatile compounds. but that they are not flammable. Blackline has not been able to recreate the alarm using the same brand of air freshener. It is therefore not clear whether the air freshener caused the alarm. However, what is clear is that it was not methane.
• The device that activated is one of three in the house. The other two did not alarm. This would be unusual if there was sufficient gas in the ground and a large cloud in the house. The one that activated is in the hallway where there is no significant pathway for gas to enter from the ground.
• Oxygen concentrations remained constant at 20.9% throughout. If there was a large cloud of gas from the ground, oxygen would have reduced slightly to around 20.4% (the gas would displace fresh air which is a mix of about 79% nitrogen and 21% oxygen) 
• Shortly after the alarm, methane was not detected anywhere inside the house using a different type of gas monitoring instrument and by two different organisations (MRSL and Cadent). Emissions of methane gas from the ground do not cause sudden large spikes in concentration that dissipates in a few minutes.
• If the alarm was caused by increased emissions from the ground, there would have been some evidence around the property or at the borehole. The monitoring that has been completed shows no change to the stable conditions.

In summary this is a “false” alarm with respect to methane (the alarm did detect a flammable gas that was present, but there are multiple lines of evidence that show it was not methane from the ground). The cause is not known. It may have been an air freshener placed above the device, but this is not certain. It is however most likely to be a household product that has caused the alarm.

11 Wagstaffe Close is safe to reoccupy, based on the preceding risk assessment.

The Blackline devices detect a range of flammable gases and not just methane. Therefore, on this site “false” alarms (with respect to gas coming out of the ground from the borehole) can be caused to the Blackline devices by some household cleaning or other products. This is the case in the event on 6 January 2025 at 11 Wagstaffe Close. A small volume of a flammable gas or gases has created a very small cloud around the sensor intake of the G7c. The concentration of the gas was sufficient to cause it to activate. 

Residents should be made aware of this and should not spray or place air fresheners, hand sanitiser or cleaning/disinfectant products close the devices.

The protocol described above with respect to investigation of a single alarm activation should be followed in future. 

While every alarm activation will continue to be responded to and investigated as a potential methane gas issue until proven otherwise, it must be acknowledged that false alarms are an inherent aspect of any alarm system.

If multiple alarms in several houses activate at the same time this is more likely to indicate a serious issue with gas emissions from the ground and borehole, and would require evacuation of all the affected houses. 

(Taken from technical report produced by EPG and approved by the Bedfordshire Local Resilience Forum Technical Cell)

The activation of the G7c device in the hallway of 11 Wagstaffe Close was not caused by methane emissions from the ground. This is based on the evidence provided by agencies that attended the activation, subsequent tests undertaken by Blackline Safety, and the following risk assessment:

• The data from the Blackline device shows that the flammable gas which activated the alarm was not methane. It was a heavier compound such as octane, an aromatic hydrocarbon, or other compound with a molecular weight greater than 80g/mol. The device has been checked at Blackline and the device is working correctly.
• An air freshener was plugged in, very close to and above the device. Some of the group of gases that could have activated the LEL alarm are common in air fresheners. The heavy gas it detected will also be heavier than air so if present in the air freshener it would sink towards the device. However, it is understood from the resident that the air freshener has been in place since the device was installed. It is not clear what temperature, or other variations, could have changed the concentration of gas reaching the device. The safety data sheet indicates it contains heavy volatile compounds. but that they are not flammable. Blackline has not been able to recreate the alarm using the same brand of air freshener. It is therefore not clear whether the air freshener caused the alarm. However, what is clear is that it was not methane.
• The device that activated is one of three in the house. The other two did not alarm. This would be unusual if there was sufficient gas in the ground and a large cloud in the house. The one that activated is in the hallway where there is no significant pathway for gas to enter from the ground.
• Oxygen concentrations remained constant at 20.9% throughout. If there was a large cloud of gas from the ground, oxygen would have reduced slightly to around 20.4% (the gas would displace fresh air which is a mix of about 79% nitrogen and 21% oxygen) 
• Shortly after the alarm, methane was not detected anywhere inside the house using a different type of gas monitoring instrument and by two different organisations (MRSL and Cadent). Emissions of methane gas from the ground do not cause sudden large spikes in concentration that dissipates in a few minutes.
• If the alarm was caused by increased emissions from the ground, there would have been some evidence around the property or at the borehole. The monitoring that has been completed shows no change to the stable conditions.

In summary this is a “false” alarm with respect to methane (the alarm did detect a flammable gas that was present, but there are multiple lines of evidence that show it was not methane from the ground). The cause is not known. It may have been an air freshener placed above the device, but this is not certain. It is however most likely to be a household product that has caused the alarm.