Sprinkler System Certifiers - Q1 Update

Our quarterly Sprinkler System Certifiers updates provide recent industry developments and solutions to common industry challenges faced firsthand – to ensure you are better informed and better advised to make better decisions. 
 

Fire Brigade Attendance Points

The Issue:  We recently received feedback from Fire and Emergency New Zealand (FENZ), where attendance points had not been approved prior to installation. 



They provided the above photograph, noting that the two doors clashed, and would not open the required 165 degrees, and that the yellow handwheel did not provide the clearance mandated in NZS4541. Their complaints are legitimate and will need to be addressed before they retrospectively approve the attendance location.

It needs to be noted that NZS4541:2020 provisions for the protection of fire fighters from falling objects is more onerous that that required by NZS4541:2013. This will need to be considered by the design team, preferably before the fire contractor is involved.

Key Takeaway: Approval of attendance points must occur before installation to prevent potential issues that may require addressing before the approval of the attendance point.   

Safety in Design

The Issue: Subsidiary isolation valves, including those for kitchen suppression systems have been installed in locations that may be problematic.

Key Takeaway: NZS4541 requires subsidiary valves to be located in an accessible area, without the need for step ladders and the like. They need to be readily assessable from floor level or other safe working environments.

This is even more important with kitchen suppression systems, where there are increased risks in installing relatively heavy agent cylinders using a ladder.
 

Extra High Hazard Design Tables

The issue: NZS4541’s extra high hazard storage design criteria are largely based on FM Global Data Sheet 8-9. When time and space allow, FM Global are carrying out a series of tests within their Rhode Island Research Campus, to validate the design criteria, in addition to establishing design criteria for new technology. 

The design tables in the latest edition of FM DS 8-9 differ from the design criteria published in NZS4541:2020. In some cases, the latest edition of FM DS requires design criteria that is more onerous than that published in NZS4541:2020 and in other cases a less onerous design criteria.

Key takeaway: If using these new design tables, designers need to be cognisant of some of the new requirements in the FM Data Sheets. For example, this could include the need to maintain 150mm flue spaces, as against the minimum 75mm allowed under NZS4541. If you are taking advantage of the newer design criteria, the requirements of the complete document that the design is based on, needs to be applied in its entirety.

Designers should consider using the most recent data, to ensure that fire systems are as reliable as is possible.
 

Institutional Heads

Institutional sprinkler heads are simply a standard sprinkler with additional features designed to make them difficult to attach a ligature device too.

The issue: It is essential to consider how they are installed. They need to be pulled hard up against a solid ceiling. To this effect, they need to be fitted with a locking ring to ensure that they cannot be pulled below the ceiling. 

If used in buildings such as forensic psychological wards, the decision as to ceiling materials need to be considered.  For example, if beneath a plasterboard ceiling, consideration needs to be given to the possibility of digging out the plaster to allow a shoelace or similar device being lodged above the sprinkler escutcheon.

Key takeaway: Alternatives to ensure that the installation is fit for purpose may be possible and should be reviewed with all parties, including Aon as the Sprinkler System Certifier prior to proceeding.
 

Diesel Fuel Bug

The issue: We were recently notified of diesel bug being discovered in both the fire and emergency generator fuel tanks at a significant facility.  

Diesel bugs can be bacterial, fungal or yeasts and can block fuel filters, starving the engine of fuel.
Diesel bugs form when water and bio-contaminants are present. Keeping tanks full will minimise condensation, and reduce the probability of bugs forming.

Key takeaway: It is recommended as a minimum, that the maintenance regime for diesel pumps include taking regular samples of fuel and carrying out a visual inspection, to ensure that the fuel appears to be clean and in good condition. A more rigorous inspection and testing program may be warranted, which could include the use of diesel bug test kits. More information can be found protecting your diesel (Diesel Bug) (z.co.nz)
 

Storage Declaration Forms

For many projects, one of the most important documents that needs to be submitted with the design parameter submission is the Storage Declaration Form.

In storage and manufacturing occupancies, this form is essential to ensure that both the designer and the certifier understand the risks and can ensure that the sprinkler system is fit for purpose.

The issue: In many cases, to allow the form to be properly filled out will require an understanding of the sprinkler standard, given the complexity of the material categorisation system.  For example,
    Is the client expecting to store idle pallets inside the sprinklered space?
    How are the goods packaged?
    Any special commodities requiring consideration in the design.

Key takeaway: We recommend that the design team (be it the consulting fire protection engineer, or the contractor’s designer) communicate clearly with the end user, to ensure that the form is correctly filled out. We have a small number of projects where the system has not been certified, as the sprinkler design did not cater for the tenant’s storage requirements. We have also seen projects where the system had to be altered after completion to allow hygienic storage of idle pallets not allowed for in the original design.
 
It is important to note that storage is not a time bound activity. In some cases, the building user is assuming that they are not storing because the materials are in process or only being held for a short period of time. Both cases are storage in the context of NZS441. 

For simple projects, where significant levels of storage outside small storage rooms is not present, we have prepared a simplified storage declaration – Aon Form 12. This form is designed to be used in occupancies such as extra light hazard through to ordinary hazard group 2.

What to learn more? Say hello to our Aon Fire Protection team today for guidance and advice to minimise fire risk. Call 0800 AON FIRE.