Compressed air in the food industry
Food Manufacturing in Australia
The next time you sit down for lunch, dinner or any meal time take a good look at your food. There’s a very good chance compressed air or nitrogen played an essential role in preparing your meal for consumption
Compressed air is a very important tool for food processing and packaging. Food production includes processes like canning, freezing, and dehydration, in fact pretty much all food production relies on compressed air. In this industry – compressed air is used for blow-off applications, cleaning, sorting, cutting, shaping, and conveying food products. It is also used to help form, fill, and seal cartons.
Q. So what standard does your air or nitrogen have to be or comply with in Australia to be safe?
A. Currently there is no universal standard set down by law in Australia governing the quality of compressed air or nitrogen in the food industry.
Sounds crazy, but this is the case. So what do we do to ensure best quality and safety to the consumer?
Air & Nitrogen Quality Standards for compressed air used in the food industry in Australia
Once hazards are identified, measures must be put in place to remove the hazards or reduce them to acceptable levels. So what level of compressed air contamination is deemed acceptable in the food industry.
Unlike compressed air that is used for breathing or medical purposes, NO standards or laws exist that define a minimum acceptable level of cleanliness (quality) when the compressed air is used for food manufacture.
As such food manufacturers have a duty of care to protect the consumer as compressed air systems are known (if not correctly treated or maintained) to carry large quantities of contamination. What actions should be taken?
If a hazard is identified such as an oil injected air compressor or piston, poor quality air or lack of maintenance or even equipment not suitable for the job then the manufacturer MUST REMOVE the hazard. Compressed air that comes into product contact either directly, indirectly or has any potential to cross contaminant must be treated (moisture removed and filters - Particles & Oil) must be added. Note FOOD GRADE oil in NOT Edible and nobody wants to see a film of oil on their coffee.
Not treating the air supply correctly may cause health and safety risks to your customers and cause irreparable damage to your brand. It is easy to avoid with the right equipment, service and installation. We are here to assist, contact us if in any doubt or if you need to improve your system.
Read best practice guidelines HERE
Food and Beverage Grade Compressed Air Best Practice Guideline 102
BCAS Guide - Our popular best practice guidance for food and beverage processors on the safe and efficient use of compressed air is now available for free download. See below.
It is always recommended that 100% Oil Free air compressors are used in food production. Usually the extra cost of this solution means it is not always selected, however you should always consider it. For more information and pricing you should contact us. Remember the cost of contamination into your food or beverage can be devastating to your business and your customers.
HACCP principle relates to compressed air
Analysis hazards in compressed air:
Atmospheric Air Compressors draw in huge amounts of atmospheric air which continuously fills the system with invisible contaminants such as:
• Water vapour • Atmospheric dirt • Oil vapour • Micro-organisms
The Air Compressor In addition to the contaminants drawn in from the atmosphere, oil lubricated compressors will contribute small amounts of oil from the compression process. The oil will be in the form of:
• Liquid oil • Oil aerosols • Oil vapour • Liquid water • Water aerosols (condensation / water from compression)
Compressed air storage devices and distribution piping
As the air leaves the compressor it now contains eight different contaminants. The air receiver (storage device) and the system piping that distribute the compressed air around the facility can store large amounts of this contamination. Additionally, they cool the warm, saturated compressed air which causes condensation on a large scale adding more liquid water into the system and promoting corrosion and microbiological growth:
• Rust • Pipescale
Contaminant removal
To operate a safe and cost effective compressed air system, contamination must be removed or reduced to acceptable limits. Failure to remove contamination can cause numerous problems in the compressed air system.
To many compressed air users, the realisation that there are ten major contaminants in a compressed air system is somewhat of a surprise. It is often thought that only three contaminants are present (Dirt / Water / Oil), however, upon closer examination, these three contaminants can be broken down further as:
Dirt • Micro-organisms • Atmospheric Dirt and Solid Particulate • Rust• Pipescale
Water • Water vapour • Condensed Liquid Water • Water Aerosols
Oil • Oil Vapour • Liquid Oil • Oil Aerosols
It is important to look at each contaminant in detail, as due to the diversity of the contamination present, a number of purification technologies must be employed for its removal.
Contamination removal is done by installing inline filtration and dryers to remove moisture & water. Each system is different and may have specific requirements but it is fair to say all system should as a minimise have a dryer & at least three levels of in line filtration. If there is direct product contact from an oil injected screw or piston
Air Quality (Purity) Requirements of the Code of Practice
6-Monthly you should conduct an air quality test on your compressed air supply.
To comply with food hygiene legislation, the food manufacturer is required to follow the principles of HACCP (Hazard Analysis and Critical Control Point) and a risk analysis must be carried out on the entire manufacturing process.
As compressed air is seen as a utility, it is often missed as a potential source of contamination. To be fully compliant, the compressed air system must be included as part of the hazard analysis and anywhere compressed air is used, classified as a Critical Control Point and subject to the air purity (quality) recommendations highlighted in section 6 of the Code of Practice. Section 6 states: The outlet compressed air must be designated as one of the following:
• Air that comes into direct contact with the food (Contact). • Air that will never come into contact with the food (Non-Contact). • Where the HACCP Hazard Analysis shows a potential risk of the Non-Contact air
indirectly contacting food or entering the food manufacturing area then the air shall be defined as Non-Contact High Risk.
Definitions Contact: Air that comes into direct contact with ingredients, finished food or beverages, packaging materials, storage vessels or the manufacturing machinery.
Non-Contact: Air that will never come into contact with ingredients, finished food or beverages, packaging materials, storage vessels or the manufacturing machinery.
Non-Contact High Risk: Air that is not supposed to come into contact with ingredients, finished food or beverages, packaging materials, storage vessels or the manufacturing machinery, but may inadvertently do so.
Dirt: The purity requirements for dirt are identical for Contact, Non-Contact and Non-Contact – High Risk. The same level of purification equipment will be required for each.
Water: The purity requirements for water vapour are identical for both Contact and Non-Contact – High Risk. This requires the Installation of adsorption dryers that deliver a Pressure Dewpoint (PDP) better than -40°C. This requirement was introduced to combat the growth of micro-organisms as compressed air with a dewpoint of -26°C or better will inhibit microbiological growth. The purity requirements of +3°C for Non-Contact will not inhibit microbiological growth.
Oil: The purity requirements for total oil are effectively identical for Contact, Non-Contact and Non-Contact – High Risk with the same level of purification equipment required for each.
Microbiological contaminants: The Code of Practice states: HACCP shall establish the risk of contamination by microbiological contaminants. The level of viable microbiological contaminants in the compressed air shall not be detectable using the test method given in ISO8573-7.
Filtration required for food production
we can assist in your selection of the right equipment
Food Grade Code of Practice
Food Grade Code of Practice
Food Grade Code of Practice
The British Compressed Air Society (BCAS) who are the governing body for compressed air and the British Retail Consortium (BRC) who represent the retail industry, have jointly developed a Code of Practice for Food Grade Compressed Air in order to assist food manufacturers . This Code of Practice evolved because of the absence of compressed air quality standards or legislation specific to the food manufacturing industries. The Code of Practice gives minimum purity (quality) standards for compressed air and defines allowable levels for dirt, water and oil, in line with air quality levels specified in ISO8573-1 the International Standard for compressed air quality. In Australia we also follow these guidelines.
Select the right equipment
Food Grade Code of Practice
Food Grade Code of Practice
To comply with food hygiene legislation, the food manufacturer is required to follow the principles of HACCP (Hazard Analysis and Critical Control Point) and a risk analysis must be carried out on the entire manufacturing process.
As compressed air is seen as a utility, it is often missed as a potential source of contamination. To be fully compliant, the compressed air system must be included as part of the hazard analysis and anywhere compressed air is used, classified as a Critical Control Point and subject to the air purity (quality) recommendations highlighted in section 6 of the Code of Practice.
Best Practice Guidelines
Food Grade Code of Practice
Best Practice Guidelines
New best practice guideline BPG 102 for food and beverage processors on the safe and efficient use of compressed air has been unveiled by the British Compressed Air Society (BCAS). This is Australia not Britain but it is this standard or guideline that we use as a basis for our industry. Following this best practice guideline in association with the food/beverage industry requirements to apply the pre-requisite programme and where applicable HACCP process will ensure that the compressed air system will not only meet current industry best practice but also contribute to customer confidence in food supplied to market.
The guideline expands and clarifies the compressed air requirements identified in existing food/beverage safety standards, guidelines and in some areas legislation. The best practice guideline is intended to provide an encouragement to the food and beverage industry to improve their compressed air provision rather than demand immediate and possibly costly expense.
Scope
Air Quality Purity Requirements
Best Practice Guidelines
This best practice guideline identifies the requirements for compressed air systems, operating at a pressure greater than 0,5 bar, as pre-requisites in the production and processing including packaging and transportation for safe food and beverage production.
It also identifies the air purity requirements for compressed air for both direct and indirect product contact.
Installation practices are provided as guidance for both existing installations and new installations.
Measurement and testing procedures are identified to verify the purity of the compressed air.
Maintenance activities are identified to retain continued performance of the compressed air system.
Air Quality Purity Requirements
Air Quality Purity Requirements
Air Quality Purity Requirements
To comply with food hygiene legislation, the food manufacturer is required to follow the principles of HACCP (Hazard Analysis and Critical Control Point) and a risk analysis must be carried out on the entire manufacturing process.
As compressed air is seen as a utility, it is often missed as a potential source of contamination. To be fully compliant, the compressed air system must be included as part of the hazard analysis and anywhere compressed air is used, classified as a Critical Control Point and subject to the air purity (quality) recommendations highlighted in section 6 of the Code of Practice.
How can we help?
Air Quality Purity Requirements
Air Quality Purity Requirements
1. We only recommend installation of the best equipment to ensure risk of failure is limited.
2. We recommend the use of 100% Oil Free Class zero air or the required equipment to eliminate the risk.
3. We can set a maintenance plan to ensure your system operates as designed. If any changes are needed we can advise.
4. An air quality test to verify the quality of your compressed air and nitrogen is recommended every 6 or 12-months.
5. We are here to help and select the right equipment for you industry.
Food and Beverage Grade Compressed Air Best Practice Guideline 102
Foreword
Since the publication of the first edition of this best practice guideline it has been pointed out that as compressed air is seen as a utility then its provision is normally included in the pre-requisite programme rather than directly as part of the hazard analysis and critical control point (HACCP) activity. This revised best practice guideline is now reformatted to reflect the change of emphasis. It is still the case that a hazard analysis shall include items subject to a pre-requisite programme to establish whether there is a need to include the compressed air provision at any specific critical control point. Compressed air is an essential part of many aspects of food/ beverage production and processing from the “farm to table” and with the ever-increasing demands to improve health and hygiene in the food chain this best practice guideline has been produced to meet those demands. The British Compressed Air Society prepared this best practice guideline with advice given by the British Retail Consortium Trading Ltd, which will give useful guidance and allow informed decisions on what type of compressed air equipment is required, how it should be installed as well as maintained, and importantly the requirements for the air purity. Following this best practice guideline in association with the food/beverage industry requirements to apply the pre-requisite programme and where applicable HACCP process will ensure that the compressed air system will not only meet current industry best practice but also contribute to customer confidence in food supplied to market. Thanks are extended to not only the BRC Trading Ltd but also those members of the British Compressed Air Society who contributed to the production of this best practice guideline.
Disclaimer This document is based upon the best knowledge available to the authors at the time of publication. However, no responsibility of any kind resulting from the use of this best practice guideline can be accepted by the authors or others involved in the publication. Reproduction of the contents of this publication, fully or in part, is forbidden in accordance with copyright laws without prior written permission from the British Compressed Air Society Ltd. This applies to any form of reproduction through printing, duplication, photocopying, recording etc. executive that includes what they do, how long they’ve been at it, and what got them to where they are.
Introduction (Informative) NOTE:
This Introduction does not form part of the best practice guideline and is provided as information only.
A. Food safety During the production, processing, handling, packaging and transporting of food/beverage at all stages from source to consumer, the safety of the food/beverage may become compromised. Contaminated compressed air is one potential source of compromise when used in conjunction with the food chain.
B. Ingredients The variation in requirements for the use of compressed air as an ingredient is considered to be beyond the scope of this document
C. Contaminants Contaminants commonly associated with compressed air are categorised in the form of dirt, water and oil. Other influences are the presence of microbiological organisms such as bacteria which may be transported through a compressed air system or propagated due to the conditions existing in a compressed air system. Contaminants that may be a potential hazard in food/beverage for human consumption need to be subject to control.
Compressed air may come into direct or indirect contact with food/beverage. Where compressed air comes into direct contact with food/beverage, in particular during production or processing, this requires a much higher level of contaminant control. Particular attention needs to be placed on sources of contaminants entering the system, that may be added during compression or emanating from the distribution system. Due to the variations in design of compressors some require oil in the compression stage and 4 some do not. For food/beverage production where the compressed air comes into direct contact the amounts of oil present and type of oil allowed is subject to strict controls. Some food/beverage producers have internal requirements where oil levels are strictly controlled.
Maintenance is a key element in ensuring that the compressor(s) and other equipment maintain acceptable operating conditions. The controls applied to all types of contaminants may either be a customer requirement or one set by regional or national legislation.
D.Codex Alimentarius - General Principles of Food Hygiene The Codex Alimentarius international food standards have become the global reference point for food producers and processors, national food control agencies and the international food trade. The code has had an enormous impact on the thinking of food producers and processors as well as on the awareness of the end users – the consumers. Its influence extends to every continent, and its contribution to the protection of public health and fair practices in the food trade is immeasurable. The Codex is the source of both the pre-requisite programme and the hazard analysis and critical control point (HACCP) philosophy and is used as the reference source in this document.
E. Pre-requisite programme and HACCP Part of the application of HACCP will consider and put in place pre-requisite programs such as good hygiene practices and training. These pre-requisite programs should be well established, fully operational and verified in order to facilitate the successful application and implementation of the complete HACCP system. I. Pre-requisite programme A food safety management system should start with a strong foundation. That strong foundation consists of procedures that address matters such as the basic operational conditions within the food/ beverage operation. These procedures are collectively termed “pre-requisite programs.” When pre-requisite programs are in place, the focus of attention can then be given to the hazards associated with the food/beverage and its preparation. Compressed air is seen as a basic operational function (utility) such as water and energy supplies in the food chain. The provision of compressed air is deemed to be a pre-requisite and as such its maintained supply and purity is essential. II. Hazard Analysis and Critical Control Point (HACCP) The Hazard Analysis and Critical Control Point (HACCP) principles which the food/beverage producer is required to perform are a key practice in the food industry. These principles are designed to ensure the quality of the final product by identifying potential contamination entry points or zones, known as Critical Control Points (CCP’s) and implementing rectification and monitoring procedures.
F. Installation This guideline sets out recommendations for compressors and associated equipment in terms of their location, air intake, ventilation and maintenance. This guideline sets out the minimum recommendation for compressed air purity in existing and new installations. Consideration has been given into the potential contamination issues surrounding compressed air and details acceptable measuring methods for testing the air purity. NOTE: - This guideline does not cover other gases commonly used in the food/beverage industry (such as nitrogen and carbon dioxide), which require separate control.
G. Guidelines and standards The guideline expands and clarifies the compressed air requirements identified in existing food/beverage safety standards, guidelines and in some areas legislation. 5 1 Scope WARNING - The text of this best practice guideline assumes that the execution of its provisions is entrusted to appropriately qualified and experienced people, for whose use it has been produced.
This best practice guideline (hereafter referenced as a “guideline”) identifies the requirements for compressed air systems, operating at a pressure greater than 0.5 bar, as pre-requisites in the production and processing including packaging and transportation for safe food and beverage production. This guideline expands on the provisions in respect of the supply of compressed air in food/beverage manufacturing as identified in the BRC Global standard for food safety, ISO 22000 and ISO TS 22002-1. It also identifies the air purity requirements for compressed air for both direct and indirect product contact. Installation practices are provided as guidance for both existing installations and new installations.
Measurement and testing procedures are identified to verify the purity of the compressed air. Maintenance activities are identified to retain continued performance of the compressed air system.
This guideline does not cover the use of compressed air as a food/beverage ingredient. 2 References The following documents are considered essential to the successful implementation of the provisions of this guideline. All documents are undated therefore the latest version applies. BRC Global Standard for Food Safety Codex Alimentarius - CAC/RCP 1 - General principles of food hygiene 6 EHEDG Doc. 23 (2nd Edition) Part 1 - Use of H1 registered Lubricants ISO 8573-1
Compressed air - Contaminants and purity classes ISO 8573-2 Compressed air for general use - Test methods for aerosol oil content ISO 8573-3 Compressed air - Test methods for measurement of humidity ISO 8573-4 Compressed air - Test methods for solid particle content ISO 8573-5 Compressed air - Test methods for oil vapour and organic solvent content ISO 8573-7 Compressed air - Test method for viable microbiological contaminant content ISO 22000 Food safety management systems - Requirements for any organization in the food chain ISO TS 22002-1 - Pre-requisite programmes on food safety - Food manufacturing BCAS Installation Guide
3 Definitions The following definitions are considered essential to the understanding of the terms used in this guideline. 3.1 Critical control point a step at which control can be applied and is essential to prevent or eliminate a food safety hazard or reduce it to an acceptable level. (CAC/RCP 1).
3.2 Direct contact process whereby compressed air is in contact as a part of the production and processing including packaging and transportation of safe food production.
3.3 Food-grade lubricants lubricants where under intended use contact with the product cannot be fully excluded.
3.4 Indirect contact process whereby compressed air is exhausted into the local atmosphere of the food preparation, production, processing, packaging or storage. NOTE: ISO TS 22002-1 uses the term ‘incidental’ which is considered to have the same meaning.
3.5 Pre-requisite programme programme that is required prior to the application of the HACCP system to ensure that the food processing facility is operating according to the Codex Principles of Food Hygiene, the appropriate guideline and appropriate food safety legislation. (Modified from CAC/RCP 52-2003) 4 Pre-requisite programme (PRP) and compressed air strategy
4.1 General A food safety management system should start with a strong foundation. That strong foundation consists of procedures that address matters such as the basic operational conditions within the food/ beverage operation. These procedures are collectively termed “pre-requisite programs.” They form part of the overall activity related to risk assessment identified as Hazard Analysis and Critical Control Points in the food chain.
4.2 Pre-requisite programme The following shall be observed in the establishment of a pre-requisite programme involving compressed air.
1. The organization shall establish, implement and maintain PRP(s) to assist in controlling:
a) the likelihood of introducing food safety hazards to the product through the work environment.
b) biological, chemical and physical contamination of the product(s), including cross contamination between products, and
c) food safety hazard levels in the product and product processing environment.
d) machinery intended for use with foodstuffs must be designed and constructed in such a way as to avoid any risk of infection, sickness or contagion.
2. The Pre Requisite Programme(s) shall:
a) be appropriate to the organisational needs with regard to food safety,
b) be appropriate to the size and type of the operation and the nature of the products being manufactured and/or handled,
c) be implemented across the entire production system, either as programmes applicable in general or as programmes applicable to a particular product or operational line, and
d) be approved by the food safety team.
4.3 Compressed air strategy The strategy to be applied for a pre-requisite programme related to the provision of compressed air shall consider the following:
a) identify areas where compressed air is involved with food/beverage
b) identify which contaminants may adversely affect the food/beverage
c) establish whether the involvement with compressed air is by direct or in-direct contact 7 4.4 Compressed air purity measures As the compressed air system is identified to form part of the pre-requisite programme its requirements will already have been identified and applied.
The measures applied shall include:
a) the air purity required i. establish the need for either direct or in-direct contact air purity at a specific point of use. ii. identify the air purity level for the entire system based on the results of the action identified in 4.4 d) and e).
b) the periodic testing to verify the required air purity
c) the service and maintenance regime necessary to maintain the air purity. These measures shall be recorded as part of the HACCP process. In addition the following steps should be taken;
d) establish whether the compressed air involvement comes within the provisions of any identified critical control points.
e) if it is within the scope of a critical control point then the steps identified in a) to c) above shall be reviewed to establish if these are adequate.
WARNING - It should be recognised that resulting from the procedure outlined in 4.4 a) ii. the air purity level requirements for the entire compressed air system may result in a level lower than the specification for direct or in-direct contact. Where this is the case it is essential that point of use air purity is carefully considered as in 4.4 d).
5 Competencies
5.1 Provision of equipment Companies involved in the supply, service and maintenance of compressed air equipment shall have staff qualified in the activities being provided. The competencies of those staff shall include compressed air principles gained from 8 formal training as well as product knowledge gained from manufacturer training. The minimum training and on the job experience shall be 5 years.
5.2 Air purity testing Personnel involved in providing services related to the testing of compressed air purity shall have competencies in the measurement standards and the practical skills necessary to interpret the results of the testing done.
5.3 Food/beverage facility Personnel employed by the food/beverage facility who are involved in any activity related to the maintenance of the compressed air system shall have sufficient knowledge through appropriate training to appreciate the requirement to maintain the air purity specifications.
5.4 Auditors It is considered good practice that personnel involved in auditing activities with respect to pre-requisite programmes and HACCP should have sufficient understanding of compressed air systems to be able to follow and complete the guidance given in Annex A to assess compliance with the pre-requisite programme as identified in the HACCP process.
6 Installation
6.1 General The requirements for the equipment included in a compressed air system for food production shall be such that the air purity specifications identified in clause 7 can be consistently met either for the entire compressed air system or at identified points of use. For guidance on general compressed air system installation the user should consult the British Compressed Air Society “Installation Guide”. Specific information on particular aspects of chosen equipment, e.g. compressor(s), dryers or filters shall be obtained from the supplier. Consideration shall be given to ‘point of use’ air treatment equipment in addition to that installed at source.
7 Compressed air purity values
The measures identified in 4.4 a) should be applied to determine the level of contamination by the use of the tests identified in clause 8 and then to verify if these levels are within the values identified in clause 7. If the values are outside of those in clause 7 then remedial action shall be taken. Whilst observing the requirements for good practice in the food industry for compressed air systems it should not be forgotten to maintain energy efficient and safe solutions.Information on Installation is given in Annex B.
7.1 Contaminant reduction requirements This guideline identifies acceptable purity values for food/beverage areas. However, consideration should also be given to any specific safety or quality requirements of the site.
7.2 Compromising compressed air purity In the event of a fault or a service requirement for the air treatment equipment provision should be made based on recognised best practice to maintain the required air purity levels. Recognised best practice may include the provision of a standby system of the same capacity and air purity specification, however any effective means of maintaining the required air purity shall be considered. It should be noted that in general compressed air applications it is common to fit a by-pass around air treatment equipment to facilitate service or maintenance. For compressed air systems included in food and beverage plants the fitting of a by-pass should be carefully considered and any procedures necessary to maintain air purity whilst the by-pass is in operation shall be fully documented.
7.3 Compressed air purity groups Compressed air used in the production of food/beverage products is divided into two groups: − air that comes into direct contact with the food/beverage; − air that could come into in-direct contact with the food/beverage.
7.3.1 Reference conditions The contaminant values for dirt and oil given in clauses
7.3.3 and 7.3.4 below are those at the ‘Reference Conditions’ in ISO 8573-1 at a temperature of 20°C, absolute atmospheric pressure of 1 bar and relative water vapour pressure of zero. The actual performance of air treatment equipment shall be as agreed between the supplier and the user which will involve relating the specified performance at reference conditions and the site conditions. NOTE – the ‘Reference conditions’ is a standardised statement of contaminant levels whereas the actual conditions on site will vary. The site conditions, temperature / atmospheric pressure / relative water vapour pressure, will be the ambient atmospheric condition existing at the point of measurement. It will be necessary to correct the actual condition values back to reference condition values to establish compliance with the contaminant levels.
7.3.2 ISO 8573-1 class designation The designation of the purity class of compressed air as given in ISO 8573-1 is written as follows, where: A is the purity class for particles; B is the purity class for humidity and liquid water; C is the purity class for total oil. 9
7.3.3 Direct contact recommendation Compressed air coming into direct contact with food/beverage should meet or exceed the following classification, Table 1, as identified from ISO 8573-1:2010 Compressed Air Purity Designation ISO 8573-1:2010 [2:2:1]
7.3.4 In-direct contact recommendation Compressed air coming into in-direct contact with food/beverage should meet or exceed the following classification, Table 2, as identified from ISO 8573-1:2010 10 Compressed Air Purity Designation ISO 8573-1:2010 [2:4:2] which translates to; Table 2 - Compressed Air Purity Designation – In-direct contact with food
7.4 Microbiological contaminants
7.4.1 General Many applications within food/beverage processes either require complete sterility or at least a level of control over the presence of micro-organisms. If compressed air containing micro-organisms is allowed to directly or indirectly contact production equipment, ingredients, packaging materials, partially completed or finished products, then sterility can be lost.
7.4.2 Control of microbiological contaminant Hazard analysis shall establish the risk of contamination by microbiological contaminants from compressed air. The level of control identified as being required over microbiological contaminants in the compressed air shall be detected using the method described in clause 8.6. NOTE: Microbiological testing of end products should not be relied upon for compressed air compliance. Class Maximum number of particles per m3 for particle sizes, d (µm) (at reference conditions see 7.3.1) 0,1 < d ≤ 0,5 0,5 < d ≤ 1,0 1,0 < d ≤ 5,0 2 ≤ 400 000 ≤ 6 000 ≤ 100 Pressure Dew-point (°C) 41 ≤ +3 Concentration total oil (liquid, aerosol, and vapour) (mg/m³)(at reference conditions) 2 ≤ 0,1 1 See Annex C.1.2.3 for information on drying of compressed air Class Maximum number of particles per m3 for particle sizes, d (µm) (at reference conditions see 7.3.1) 0,1 < d ≤ 0,5 0,5 < d ≤ 1,0 1,0 < d ≤ 5,0 2 ≤ 400 000 ≤ 6 000 ≤ 100 Pressure Dew-point (°C) 2 ≤ -40 Concentration total oil (liquid, aerosol, and vapour) (mg/m³)(at reference conditions) 1 ≤ 0,01 A summary of the technologies for purification of compressed air can be found in Annex C.4.
8 Verification of air purity requirements
8.1 General The methods to be employed to verify the level of contaminants shall follow those test methods described in the appropriate part of ISO 8573. Other methods using chemical indicator tubes may be used to establish the general levels of oil and humidity. Guidance should be sought from the original equipment manufacturer of the compressed air equipment on testing and compliance procedures.
8.2 Periodicity WARNING: The compressed air purity test procedures require qualified personnel and specialised equipment consult your supplier for advice on suitable air purity measurement providers. The compressed air purity shall be tested and verified at least twice per year, unless otherwise identified in the HACCP process, or in accordance with manufacturers recommendations using the methods identified in the following clauses. NOTE: Whenever maintenance work or any activity that may affect the air purity is performed on the compressed air system then as a simple check on the air purity chemical indicator tubes may be used. This method may be employed where the next scheduled periodic test is not imminent.
8.3 Dirt (Solid particles) Solid particles shall be measured in accordance with ISO 8573-4. In addition to using this method to measure particles ISO 8573-7 as indicated in clause 8.6 shall also be done to confirm whether there are any microbiological colonies present in the solid particles from the compressed air.
9 Service and maintenance
The compressors and all ancillary components that are involved in producing compressed air to the purity levels stated in this guideline shall be maintained to the level identified by the original equipment manufacturer. It is a requirement of this guideline that service and maintenance shall be performed by qualified personnel using industry best practices. Industry best practices should extend to the use of replacement parts as provided by the original manufacturer in order to provide the confidence that original performance can be maintained. Alternative parts should only be used if the supplier can prove performance of the alternative part is equal to or exceeds the performance of the original. Further information on maintenance is given in Annex D. 10 Documentation All measurements related to the air purity requirements shall be recorded and documented. All maintenance work shall be recorded and documented. All documentation received with any equipment included in the compressed air supply shall be kept in a log created specifically to assist with maintaining up-to-date information on the system and for reference during any audit.