Section I - Ground Criteria
27. Each Club shall provide and maintain at its registered ground an undersoil heating system or
some other adequate system of pitch protection to the reasonable satisfaction of the Board
which shall be operated to the extent necessary to procure, so far as is reasonably possible,
that the pitch is playable on the occasion of each home League Match.
Premier League rules seem to be applied with some randomness. Whilst you could argue that Blackpool are broke and need time to comply, you could also say 'tough' and remember that Stevenage (was it?) were denied entry to the football league because their ground didn't meet the criteria.
Birmingham City finally had it installed in 2009. Middlesboro took ages after the Riverside was built.
Are there any other current clubs hiding behind this 'other adequate system' clause? Clearly Blackpool's system is not adequate and they are in breach.