Last edited 14 Feb 2019

BREEAM Impact of refrigerants

Contents

[edit] Aim and benefits

To reduce the levels of greenhouse gas emissions arising from refrigerants leaking in the development.

[edit] What's the problem with refrigerants?

Chlorinated refrigerants (chlorofluorocarbons – CFCs, and to a lesser extent, hydrochlorofluorocarbons - HCFCs) contribute to the depletion of stratosphericozone if released into the atmosphere due to equipment leaks or if refrigerants are not properly recovered when disposal of the equipment takes place.

Due to their stability in the atmosphere, CFCs as well as HCFCs and HFCs are often very effective greenhouse gases. The GWP factor is used to reflect their impact on global warming. The GWP is the ratio of the warming caused by a substance to the warming caused by a similar mass of carbon dioxide.

Refrigerant leaks can causes humans to be exposed to high levels of chemicals whcih can cause minor issues with the skin such as dryness and irritation.

[edit] When to consider

At the pre-assessment, it's useful to establish:

- Will there be refrigerants? Will they likely have more than 6kg charge in each unit?

- Are there any plans to use a very low GWP refrigerants?

- Are we planning to have chillers? or a VRF system?

- The pre-requisite may be the stumbling block for this credit, confirming compliance can be difficult and time consuming!

[edit] Step by step guidance

Pre-requisite
All systems (with electric compressors) must comply with the requirements of BS EN 378: 2008/ 2008 +A2: 2012/ BS EN 378: 2016 (parts 2 and 3) and where refrigeration systems containing ammonia are installed, the Institute of Refrigeration: Ammonia Refrigeration Systems Code of Practice.

For the pre-requisite you’ll need to confirm that the units will be installed to BS EN 378:2008 (Refrigerant Systems and Heat Pumps. Safety and Environmental Requirements) or as the 2008 edition has been superseded, you’ll need to confirm that the units will be installed to BS EN 378: 2016 (The 2016 edition incorporates additional refrigerant types, but both documents have the same methodology for Classification A1 refrigerants i.e. R410A, although page numbers may be different).

BREEAM UK NC 2014 specifies BS EN 378: 2008

BREEAM UK NC 2018 specifies BS EN 378: 2016

BREEAM UK RFO 2014 specifies BS EN 378: 2008

BREEAM International NC 2016 specifies BS EN 378: 2008 +A2: 2012 or ISO 5149:2014

BREEAM International RFO 2015 specifies BS EN 378: 2008 +A2: 2012 or ISO 5149:2014

From the BS:

Part 1 deals with ‘Basic requirements, definitions, classification and selection criteria’; and provides the calculations to be used in A/C systems design which is covered by Part 2.

Part 2 deals with ‘Design, construction testing, marking and documentation’. (Requires evidence from the designer and the manufacturer)

Part 3 deals with ‘Installation site and personal protection’.

Part 1: (calculations will be required to assistance evidence for Part 2)

Using BS EN 378-1: 2008 – Page 18 – you will need to confirm the ‘refrigerant systems classification’.

Using BS EN 378-1: 2008 – Page 19 and Table 1 Category of occupancy (page 20) – you will need to confirm the ‘Occupancies’.

Using BS EN 378-1: 2008: Table C.1 Refrigerant Safety Groups (page 38 onwards) – you will need to confirm the ‘Refrigerant Safety Group – A1’ and the calculation required e.g. Box 1: Maximum charge = practical limit x room volume.

You will need to confirm the Safety Group from the refrigerant type i.e. R410A, R32 etc.

The practical limit is given in BS EN 378-1: 2008, Annex E, Table E.1, E.2 & E.3 as applicable – Refrigerant designations. For example:

Table E.1 – Refrigerant designations – R32 = 0.061kg/m3

Table E.2 – Refrigerant designations of R400 blends – R410A = 0.44kg/m3.

Therefore, the calculation using R410A for Box1: Maximum charge = practical limit x room volume for each applicable room served and where pipework runs through, equals:

'Example Room 1'

You will need to reference drawings or room data sheets etc. to confirm the width, depth and height to enable the volume to be calculated e.g.

Drawing Ref. XX-XX-01-A-XX-DR-XXX-XXX-C14_GA GF Plan – confirms floor area as 60.7m2.

Drawing Ref. XX-XX-01-A-XX-DR-XXX-XXX-C14_GA GF Section – confirms FFL to U/S of structural slab as 3.3m, therefore:

60.7m2 (a) x 3.3m (h) = 200.31m3 (room volume)

0.44 x 200.31 = 88.14kg maximum charge

If for example the proposed system has a charge of 10kg then the room is compliant.

You will need to repeat calculations for each room, including where pipework runs through a room as applicable.

Therefore, in this example as the proposed system has a charge of 10kg per unit (approximately 89% less than the maximum allowance for Room 1), no restrictions (i.e. leak detection) are required.

Therefore Part 1 is compliant and enables Part 2 to be completed.

Part 2:

From the Designer: You will need to confirm the systems design. Types of evidence to confirm this might be specification, engineering report, drawings and manufacturer’s literature etc. If the system is to be selected by sub-contractor, you’ll need to confirm the requirements at the design stage that the sub-contractor will need to comply with?

From the Manufacturer: You will need to provide evidence such as a Declaration of Conformity, Literature that confirms compliance with BS EN 378-2: 2008 or 2016. (This is often difficult to obtain? However, generally satisfactory at the design stage is a drawing annotation to confirm that the system(s) must comply with the standard, at the construction stage this annotation needs to remain on the ‘As-Installed’ drawing – this is not irrefutable evidence, but seems to be about the most resilient for the time being?)

Part 3:

You will need to confirm the site installation procedure (e.g. a risk assessment and method statement should suffice, which includes any site wide protection and/ or personal protective equipment required) and that full commissioning sheets will be required at practical completion to confirm compliance with the Standard. This could be annotated on a drawing at the design stage and retained at on the construction stage ‘as-installed’ drawings (Again this is not irrefutable evidence!)

You will need to communicate this to (design/ installation) sub-contractors to ensure that these annotations are provided on ‘As-installed’ drawings.

[edit] Questions to ask while seeking compliance

Will the development be predominately naturally ventilated but require small scale hermatically sealed units to a couple of spaces i.e. internal meeting rooms, comms rooms? - if 'yes' then the pre-requisite will need to be satisfied.

[edit] Tools and resources

A copy of the British Standard will be required to prepare the pre-requisite calculations.

[edit] Tips and best practice

Frequently, your M&E engineer may well nod along that these credits are all achievable. Please consider:

- DELC <100 or GWP <10 -- Unless you're using a "strange" system with refrigerants such as ammonia, water -- you probably won't achieve these credits. Less than 1000 however, is relatively OK if you use R134a/R32 or something similar.

- You probably (as of Jan 2018) won't find a leak detection system for a VRF system, only if you have centralised chillers.

[edit] Typical evidence

Drawings/ rooms data sheets to be able to calculate 'room volumes'.

Drawings which show where the units will be positioned and the connecting pipework runs, so that all calculations can be made.

Confirmation of the refrigerant to be used.

A copy of the relevant BS EN 378 to be able to confirm the 'refrigerant systems classification', the 'occupancies' and the 'refrigerant safety group'.

Specification, engineering report and/ or manufacturer's literature to confirm the design/ type of system to be installed.

Manufacturer's Declaration of Conformity/ Literature which confirms compliance of the equipment with the BS.

Risk assessment/ method statement/ procdeural document to confirm the site installation procedure.

At the construction stage (in addition to the above) photographs and as-installed drawings.

[edit] Applicable Schemes

The guidelines collated in this ISD aim to support sustainable best practice in the topic described. This issue may apply in multiple BREEAM schemes covering different stages in the life of a building, different building types and different year versions. Some content may be generic but scheme nuances should also be taken into account. Refer to the comments below and related articles to this one to understand these nuances. See this document for further guidelines.

  • BREEAM UK NC 2014 specifies BS EN 378: 2008

    BREEAM UK NC 2018 specifies BS EN 378: 2016

    BREEAM UK RFO 2014 specifies BS EN 378: 2008

    BREEAM International NC 2016 specifies BS EN 378: 2008 +A2: 2012 or ISO 5149:2014

    BREEAM International RFO 2015 specifies BS EN 378: 2008 +A2: 2012 or ISO 5149:2014


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--Multiple Author Article 22:16, 21 Apr 2018 (BST)