Single Penetration Seal
Just like it sounds, a single penetration is a single hole for a single service (or group of the same services). For instance, an individual cable (or bundle of cables) passing through a wall.
Single penetrations may also be referred to as a ‘direct to wall’ seal or a ‘direct to floor seal’ as they often require a single product fixed/sealed directly around the services.
In contrast, a ‘multiservice penetration seal’ is where different types of services penetrate the one aperture. For instance, a letterbox aperture above a flat entrance door maybe containing a sprinkler pipe, cable tray, hot and cold water feeds and a plastic ventilation duct.
Multiservice penetration seals typically require a Fire Batt or Fire Protection Compound to complete the larger oversized aperture. Services are then sealed with individual fire stop seals that are fitted within, or to, the overall seal.
In accordance with BSEN1366-3:2021 section 13.7, there must be a minimum of 100mm between penetration seals, unless tested otherwise. So, whilst direct to wall seals/single penetrations might be an attractive proposition, multiple service spaced at least 100mm between seals may not be practically achievable.
Therefore, a multiservice penetration fire batt seal which has been ‘tested otherwise’, with a lesser spacing requirement, may be a more appropriate option.