As a rule, liquid reagents do not consist of a single preparation but comprise several components that need to be added to the sample in a certain order. As both the size and the number of drops have a decisive effect on the resultant colour complex, the reagents need to be added with a high degree of precision.

The useful life of liquid reagents is reduced by temporary contact with oxygen in the air when the bottle is opened as well as by unsuitable storage environments (presence of sunlight or high temperatures). Provided that the bottles are stored within the temperature range + 15 °C to + 25 °C, the Lovibond® DPD and Phenol Red solutions can be used for a period of two years from the production date.

NOTE: 

There has recently been an amendment to the UK Poisons Act 1972 regarding the supply of Explosives precursors which comes into effect from October 1^st 2023 and covers the supply of certain materials. 

In order to comply with these regulations we kindly ask that you complete the following actions as quickly as possible in order to avoid disruption to supply.

• Please complete this form, along with a copy of a photographic ID (such as a passport, driving licence, trade ID card, business ID card) for the individual that your company authorises to purchase these materials.
• You will need to understand your legal obligations under the Act, particularly in regard to the reporting of loss, theft or suspicious activity.
• If you are reselling these materials then you may need to obtain and retain the same information from your customers.

Further information can be found at https://www.gov.uk/government/publications/supplying-explosives-precursors/supplying-explosives-precursors-and-poison