Frequently Asked Questions

Frequently Asked Questions

Questions here are our most frequently asked, and include topics on sampling media, methods, regulatory standards, and lab reports.


What are your hours of operation?

Assay Technology, Inc currently operates two facilities:

Main Office

1382 Stealth Street

Livermore, CA 94551



Hours of operation:  Monday through Friday, 7:30 to 5 pm PST

All phone calls are received in the main office.

All shipments are sent from the main office in Livermore, CA.

Ohio Office

250 DeBartolo Place, #2525

Boardman, OH 44512

Hours of Operation:  Monday through Friday, 7:30 am to 4:30 pm EST


Customers are asked to call the California office


What is Assay Technology's holiday schedule?

Click on this link to see our holiday schedule.

Web Store

What's new?

What isn’t new? It’s all new.

  • If you know what you want to order, use the Online Ordering form. It is much easier and faster. Note the items with the higher part numbers are listed first. Online ordering is always available at the top of the page.
  • The store is integrated in the site. No more back and forth between our website and our store.
  • The store will automatically notify customers when a product can’t be shipped over a weekend/holiday.
  • Once a shipping address is entered, the store will add and remove shipping options automatically depending on your location and what day you are ordering.
  • If you want someone to walk through the new site with you, give us a call or watch our video about the new site.

Where do I go to buy?

  • If you know what you want to order, use the Online Ordering form. It is much easier and faster.  Note the items with the higher part numbers are listed first. Online ordering is always available at the top of the page.
  • If you do not know the item number, go to the product summaries and use our assistant.

Why shop online?

  • You can save 10% on all our biggest selling items, X and N boxes.
  • It’s faster and easier than ever before.

Are all items discounted online?

No. X products (boxes of 5 badges with analysis) and N products (boxes of 10 badges without analysis) are sold online at a 10% discount. Single badges (W’s) and media (M’s) are not discounted online.

Are all items sold online?

No.  Items not sold online include:

  • Sampling media we do not manufacture: tubes, cassettes, wipes.
  • AT Lab testing fees that are not prepaid.
  • MNR testing and instruments.

Usually, purchasing these items requires a conversation because they are more complex than badges. We recommend calling Customer Support at 800-833-1258 option 4.

Prepaid Analysis

Why would I prepay for analysis?

Because it saves you time and money.

Customers can purchase samplers with the analysis at AT Labs’ AIHA-LAP, LLC accredited laboratories already pre-paid. Since both the monitor and analysis is sold at the same time, the price is significantly lower than buying them separately. The -1 products come with the analysis of one chemical prepaid. The -4 products come with the analysis of up to 4 chemicals. These two choices satisfy most customers’ needs.

At times, customers will need more chemicals than they have prepaid. When this happens, they can simply request the additional chemical and they will be billed for it after the report is completed. The price will vary depending on the type of analysis. The easiest way to determine how much more is to give us a call. However, to determine the price yourself, go to Sampling Guide, and search for your chemical. Then expand the information for that chemical and you will “Price Code Compatible Chemical” column(E.g. A705-X, A707-X).  Go to the Price List to determine the price per extra chemical.

Sampling Media

Are diffusive badges recommended for compliance sampling?

Yes. All Assay Technology personal monitors meet and/or exceed the OSHA accuracy and precision criteria for sampling and analytical methods. Samplers have been validated for performance under a wide variety of sampling conditions.

However, OSHA does not specifically recommend or approve specific types of air monitoring products.  Please read Dr Manning’s post about OSHA and NIOSH Approval

Why can't some chemicals be analyzed together even though they can be collected on the same type of badge?

This question is best answered through examples:

Example 1: The customer wants to collect and analyze total hydrocarbons and isopropyl alcohol on a single 566 badge. But customer service calls and says it can’t be done. The customer is confused because both total hydrocarbons and IPA can be collected and analyzed on the 566. Customer service insists total hydrocarbons is a list C chemical and IPA is a list A chemical and can’t be analyzed on the same badge.

  • List A:  Carbon disulfide is the primary solvent for extracting (nonpolar) chemicals  from carbon. So, hexane, xylenes are OK, but methanol and acetone are not.  Their recoveries are too low.  But, if you add another solvent (co-solvent) to the mix, you can add many polar chemicals to the list.  Alcohols, ketones, acetates.  At AT Labs, we use benzyl alcohol. So, our standard solvent mixture is 97% carbon disulfide and 3% benzyl alcohol. For most badges received, this is an excellent solvent mixture.  However, when you analyze for “total hydrocarbons,” you have to use a solvent mixture that doesn’t block the scan. Approximately, C4 through C15. And benzyl alcohol blocks C11 through C13. Thus, you can’t analyze for IPA without the co-solvent, and you can’t analyze total hydrocarbons with the co-solvent.

Example 2 (keeping example 1 in mind): Why is there a list B?  List B contains chemicals that are blocked by the benzyl alcohol. Instead of benzyl alcohol, we use n-butanol, which blocks other chemicals, but again allows the lab to include many polar and nopolar chemicals.

On the Sampling Guide, we show which chemicals can be analyzed together in the Test Group column. All chemicals with the same Test Group can be analyzed together (unless the Test Group is blank.) The new Guide allows you to filter on Test Group, so you can see everything that can be analyzed together.  Keep in mind this works for other badges, like amines, aldehydes, and metals.

Are blanks required by the lab for the analysis of Assay Technology personal monitors?

  • Media Blanks: It is not required that customers submit blanks when using Assay Technology badges. The laboratory is always analyzing our own badges. We will automatically analyze a blank monitor with every analytical batch and blank correct as appropriate.
  • Field Blanks: Field blanks are definitely recommended. These should be ordered and returned with your samples, however not exposed at any point. They monitor and correct for any background contamination that may have occurred during storage, handing or shipping. They are especially useful for gases like nitrous oxide and ethylene oxide.

Why are blanks required by the lab for each set of sampling tubes or cassettes I submit?

  • Media Blanks: Since Assay Technology does not manufacuture this media, nor does it analyze this media regularly, we require the customer provide a blank with their samples to be added or a blank will be added for them so the background, if any can be corrected for. However, if the customer provides a field blank, the laboratory will analyze a media blank, free of charge.
  • Field Blanks: The use of field blanks to monitor and correct for any background comtamination that may have occurred during storage, handing or shipping is recommended. Unless requested, the laboratory does not Field Blank correct results.

What does sample capacity mean and why should I care?

Sample capacity is a measure of the amount or exposure of contaminant(s) that a sampler can collect without becoming saturated, leading to a biased low result.

Customers frequently want the fastest sampler possible so they can get the lower reporting limits without regard to the sampler’s capacity to retain the chemical it is exposed to. This is an incorrect way to sample.

Assay Technology has 3 types of Organic Vapor monitors to handle a variety of environments:

521:  This super fast sampling badge is great for IAQ, STEL, and chemicals with low PELs, <10 ppm. But if it is exposed to 500 ppm of a chemical, it’s capacity will be used up if used all day and the results for this badge will be biased low.

566:  Our most versatile badge for STEL and PEL. When asked which badge should be used, usually the answer is the 566 badge.

546:  Our slowest sampling badge. The reporting limits will be higher, but the 546 is very useful when you need to monitor chemicals with very high PELs, all day. If you have 750 ppm of acetone, you are below the PEL, but you risk saturating a 521 badge if you use it for 8 hours. However, the 546 badge will be fine. If the PELs are high and you need to monitor for 8 hours, use the 546.

The sample capacity is listed on the technical inserts that come with the product and can be found on the website in the product summary for the badge.  Product Summary

For badges that collect many, many, chemicals–contact customer service.

What is the minimum face velocity requried for the badges to function as claimed?

The badges have been tested between 15 and 150 cm/sec.  We expect the badges will continue to function as claimed at velocities higher than 150 cm/sec.

In general, the badges should not be used in a drawer or closed cabinet.  The results would be biased low.  To monitor inside these areas, use a very small fan to move the air around.

Badges can be hung in a room with normal air flow caused by air condition units.

How do I know which media to use for sampling specific chemicals?

Please refer to Assay Technology’s Industrial Hygiene Sampling Guide for a complete listing of chemicals, and appropriate sampling media. Guidelines are based on OSHA and NIOSH sampling methods, and include media types for both diffusive and active testing.

Where can I send my samples for analysis by an AIHA-LAP, LLC accredited lab?

In addition to being a manufacturer, Assay Technology operates two accredited industrial hygiene laboratories. If you have prepaid for the analysis be sure to send them to our labs. The instructions sent with the badges or media will indicate which laboratory is best to send the badges to. However, if you send the badges to the wrong lab, we will send the badges where they need to go without extending the due date.

If you received badges from another laboratory, be sure to send them to that lab for analysis. 

I am having trouble removing the covers from the TraceAir badges (521 and 580).

To begin sampling with the TraceAir monitors, one or two covers must be removed. It is up to the customer how many they want to remove. Most customers remove both covers to obtain the lowest reporting limits possible.  Contact us for assistance if you have a question about this. Sometimes, customers pull apart the badge trying to get the covers off. Usually, they are pulling the covers off from the middle of the badge. It is much easier to remove the covers from the bottom. Please review the slide show that shows how to best remove the covers. Call us if you have further questions.

We have developed the TraceAirII badge design to address this common complaint. The 581 TraceAirII high sampling rate aldehyde badge has replaced the 580 badge.  The 525 TraceAirII high sampling rate organic vapor badge has reported the 521 badge.  For more information:  TraceAirII


What does "Store Under Refrigeration" mean?

Some of the Assay badges are marked “Store Under Refrigeration”. This leads to many questions.  Here are the answers to frequently asked questions about refrigeration:

  • When the product is shipped, it does not need to be refrigerated.  However, the longest it should be in transit from Assay to you is TWO calendar days.
  • Do not ship over a weekend. If a customer places an order on a Thursday, the product has to be shipped overnight, marked to arrive Saturday or shipped out on Monday.
  • Once the shipment is received, store in a refrigerator before use. (Note:  Only the 595 badge has to be shipped back cold. No other badges require refrigeration after collection. However, refrigeration after use is OK.)
  • For a badge that is supposed to be stored under refrigeration, but was stored at room temperature or higher for a few days, we suggest using one of the badges as field blanks to correct for any background issues that may have occurred.

Which lab do I ship my badges/media to after use?

  • The instructions sent with the badges indicate which lab performs the analysis.
  • If you do not have the instructions, use this guide.
  • If you are not sending a badge back for analysis (eg a tube), call us or just send to the Ohio facility.
  • If you have one badge that goes to California and one badge that goes to Ohio, send them both to either lab. We will send the badges where they need to go, and report them together (unless you don’t want that), and not extend the due date. An exception to this is when you need a rush analysis. Then, it is very important to send the badges to the correct laboratory.

Does Assay Technology receive packages on Saturday?

Both laboratories receive badges Monday through Friday.  Saturday deliveries are possible, but call in advance so arrangements can be made.


Can I use sampling methods, other than those recommended by OSHA, NIOSH, or other government agencies?

Yes. OSHA does not require, or mandate, the use of a particular sampling method. Rather, OSHA and NIOSH set forth criteria for the accuracy and precision of sampling and analytical methods. An employer is obligated to select a method that meets these criteria, relative to their specific sampling conditions. Typically, these criteria for sampling at the permissable exposure limit, must be within +/- 25% of the true value, at a 95% confidence level. Alternative methods, with supporting validation data to demonstrate the accuracy and precision of the methods, are acceptable for OSHA compliance monitoring.

How do I determine which sampling method is better to use?

When multiple methods are published by OSHA and NIOSH, the user should consider a number of criteria, specific to the sampling situation. These include type of media preferred, analytical method, detection range, and any possible interferences. Talking with your laboratory is recommended, to address other limitations or advantages of one method over another. Generally, the more current the method, the better, in that problems of earlier methods have been corrected.

Are the sampling rates listed in methods, or the Sampling Guide, exact, or can I sample at variable rates?

Most methods list an acceptable range of both sampling rates and air volumes that would apply to the majority of sampling situations. Staying within these ranges is recommended to ensure the validity of the method. When variations are made, quality control data points should be obtained to demonstrate the validity of the method under the new conditions.

Can badges be used to sample formaldehyde when the source is Formalin?

In OSHA Method 1007, OSHA warns of possible sampling error when using any diffusive sampler in environments where the source of
formaldehyde exposure is formalin. Dr. Manning responded in this technical opinion.


How can I get copies of air sampling methods?

Both OSHA and NIOSH have sites devoted to their sampling and analytical methods. Links to the applicable methods are available on our Sampling Guide.

Questions about the Laboratories and reading reports.

Lab Report FAQs

Go to our Lab Report FAQs.